This document discusses water activity (aw), which is a measure of the amount of water available in a food to support microbial growth. It defines aw and explains how it is measured using various methods like vapor pressure, osmotic pressure, and equilibrium relative humidity. The document discusses why aw is important in determining microbial spoilage and outlines typical aw levels for microbial growth. It also provides examples of aw values for different foods and discusses advantages and disadvantages of measuring aw.
Water activity is the moisture content of the food which is available for microbial growth.By controlling water activity the food can be preserved for longer duration
Water plays an important role in many foods, affecting texture, enabling chemical reactions, and supporting microbial growth. Many fresh foods are composed of 75% or more water. There are three forms of water in foods: free water, which can be squeezed out; absorbed water, which is attached to molecules like proteins and carbohydrates; and bound water, which is trapped within crystals or other substances and cannot promote microbial growth. Determining the moisture content of foods is important for factors like shelf life and susceptibility to contamination.
Water activity and types of food based on water activitySaptadeep Sanyal
Water activity is a measure of available water in a food and is important because it determines microbial growth. It is defined as the ratio of vapor pressure of water in a food to vapor pressure of pure water at the same temperature. Foods with water activities below 0.6 inhibit mold growth, increasing shelf life. Controlling water activity through addition of solutes like salt or sugar allows some foods to be stored without refrigeration as intermediate moisture foods.
Basics of sorption isotherm & its applications in food processingDhruv Patel
The document discusses moisture sorption isotherms, which describe the relationship between water activity and moisture content in foods. It covers how temperature, hysteresis, and food composition affect isotherms. Measurement methods include gravimetric, manometric, and hygrometric techniques. Sorption isotherms have important applications in food processing and storage, such as designing drying equipment, predicting shelf-life and quality changes during storage.
Water activity and different instruments to determine AwAbel Jacob Thomas
This presentation includes water activity, its importance, equations, food sorption isotherm, different instruments to determine the water activity of a food product.
Thermal and non-thermal food preservation technologies.pptxVAIBHAV PATIL
This document discusses thermal and non-thermal food processing technologies. Thermal technologies discussed include blanching, pasteurization, and sterilization which use heat to destroy microbes and enzymes. Non-thermal technologies discussed include high pressure processing, food irradiation, pulsed light/electric field, and ultrasonics which achieve food preservation without heat. Both thermal and non-thermal technologies are aimed at reducing food losses and extending shelf life while ensuring food safety, though non-thermal methods maintain nutritional and sensory qualities of food better than thermal methods. The document concludes that a combination of thermal and non-thermal treatments may be most effective for food processing.
Ultra High Temperature Processing of Food ProductsSourabh Bhartia
The document discusses ultra high temperature (UHT) processing of food products. UHT processing involves heating food to 135°C for 2-5 seconds to kill microorganisms and spores. This allows for longer shelf life without refrigeration. There are two main methods - direct heating which applies steam directly to the food, and indirect heating which uses a partition between the food and steam. Indirect heating includes plate heat exchangers, tubular heat exchangers, and scraped surface heat exchangers. UHT processing offers benefits like longer shelf life and packaging flexibility but requires complex sterile processing equipment.
This document summarizes the properties of water and its role in food. It discusses how water is essential for life and plays many important roles in food processing, quality, and microbial growth. It defines water activity and explains how it determines what microorganisms can grow in different foods. Various water activity values are provided for different microorganisms and common food products. The different types of bottled water are also outlined.
Water activity is the moisture content of the food which is available for microbial growth.By controlling water activity the food can be preserved for longer duration
Water plays an important role in many foods, affecting texture, enabling chemical reactions, and supporting microbial growth. Many fresh foods are composed of 75% or more water. There are three forms of water in foods: free water, which can be squeezed out; absorbed water, which is attached to molecules like proteins and carbohydrates; and bound water, which is trapped within crystals or other substances and cannot promote microbial growth. Determining the moisture content of foods is important for factors like shelf life and susceptibility to contamination.
Water activity and types of food based on water activitySaptadeep Sanyal
Water activity is a measure of available water in a food and is important because it determines microbial growth. It is defined as the ratio of vapor pressure of water in a food to vapor pressure of pure water at the same temperature. Foods with water activities below 0.6 inhibit mold growth, increasing shelf life. Controlling water activity through addition of solutes like salt or sugar allows some foods to be stored without refrigeration as intermediate moisture foods.
Basics of sorption isotherm & its applications in food processingDhruv Patel
The document discusses moisture sorption isotherms, which describe the relationship between water activity and moisture content in foods. It covers how temperature, hysteresis, and food composition affect isotherms. Measurement methods include gravimetric, manometric, and hygrometric techniques. Sorption isotherms have important applications in food processing and storage, such as designing drying equipment, predicting shelf-life and quality changes during storage.
Water activity and different instruments to determine AwAbel Jacob Thomas
This presentation includes water activity, its importance, equations, food sorption isotherm, different instruments to determine the water activity of a food product.
Thermal and non-thermal food preservation technologies.pptxVAIBHAV PATIL
This document discusses thermal and non-thermal food processing technologies. Thermal technologies discussed include blanching, pasteurization, and sterilization which use heat to destroy microbes and enzymes. Non-thermal technologies discussed include high pressure processing, food irradiation, pulsed light/electric field, and ultrasonics which achieve food preservation without heat. Both thermal and non-thermal technologies are aimed at reducing food losses and extending shelf life while ensuring food safety, though non-thermal methods maintain nutritional and sensory qualities of food better than thermal methods. The document concludes that a combination of thermal and non-thermal treatments may be most effective for food processing.
Ultra High Temperature Processing of Food ProductsSourabh Bhartia
The document discusses ultra high temperature (UHT) processing of food products. UHT processing involves heating food to 135°C for 2-5 seconds to kill microorganisms and spores. This allows for longer shelf life without refrigeration. There are two main methods - direct heating which applies steam directly to the food, and indirect heating which uses a partition between the food and steam. Indirect heating includes plate heat exchangers, tubular heat exchangers, and scraped surface heat exchangers. UHT processing offers benefits like longer shelf life and packaging flexibility but requires complex sterile processing equipment.
This document summarizes the properties of water and its role in food. It discusses how water is essential for life and plays many important roles in food processing, quality, and microbial growth. It defines water activity and explains how it determines what microorganisms can grow in different foods. Various water activity values are provided for different microorganisms and common food products. The different types of bottled water are also outlined.
Hurdle technology uses a combination of preservation methods to make foods shelf-stable while maintaining quality and safety. It involves using multiple hurdles like reduced moisture, increased acidity, refrigeration, or addition of preservatives that microorganisms must overcome to grow. The hurdles work synergistically so that microbes cannot adapt to or overcome all of the preservation factors simultaneously. This allows foods to be processed more gently and minimally while still achieving a long shelf life.
Blanching is a heat treatment of fruits and vegetables that inactivates enzymes and microorganisms. It involves rapidly heating produce to a specified temperature for a short time period, then rapidly cooling it. This helps prevent quality degradation during further processing like freezing, canning, or drying by stopping enzymatic and microbial activity. Blanching also softens tissues, removes gases, and helps with peeling or packaging of produce. However, it can result in some nutrient and texture loss depending on the time-temperature combination used.
Non thermal process in preservation of foodGazanfar Abass
The document discusses various non-thermal food processing techniques as alternatives to traditional thermal processing. It provides examples of different non-thermal methods like pulsed electric field, high pressure processing, pulsed light technology, microwave heating, ohmic heating, and irradiation. These methods aim to increase production rates and profits for food industries while maintaining better quality, nutrients, flavor and extending shelf life compared to thermal processing which can result in loss of volatile compounds. The non-thermal methods are particularly suitable for large scale and liquid food production.
The document discusses the functional properties of proteins in foods. It begins by defining functionality as any non-nutritive property that influences an ingredient's usefulness. It then identifies three main groups of functional properties: hydration properties related to protein-water interactions like solubility and viscosity; properties related to protein-protein interactions like gelation and dough formation; and surface properties involved in emulsification and foaming. Specific examples covered include the role of proteins in viscosity, gelation, emulsions, foams, and dough formation. The document concludes by noting how extrusion and enzymatic hydrolysis can alter soy protein properties.
Baking and roasting are similar processes that use heated air to alter the quality of foods. Baking is typically used for flour-based foods and fruits, while roasting is for meats, nuts and vegetables. Both processes involve heat transfer through radiation, convection and conduction to cook foods internally without exceeding 100°C. This causes surface changes that improve qualities like moisture retention. Ovens can be direct or indirect heating types, and batch, continuous or semi-continuous systems. Frying methods include deep frying by full submersion in hot oil, shallow frying with partial submersion, and stir frying using minimal oil. Frying oils undergo hydrolysis and oxidation over time, producing compounds that degrade quality
This document discusses intermediate moisture foods (IMF), which are foods with a water activity between 0.6-0.9 that prevents microbial growth. Examples include jams, jellies, candies, baked goods, honey, and dried meats. IMF have 10-50% moisture. Water activity measures the availability of water for microbial growth. IMF provide food preservation by controlling water activity and may include additional preservatives. While IMF don't require refrigeration, they can contain high sugar or salt and their texture may deteriorate if not properly handled.
Hurdle technology involves using two or more preservation methods together to inhibit microbial spoilage of foods. It allows for safer, stable foods without refrigeration. Common hurdles include reduced pH, increased salt content, reduced water activity, and heat processing. The hurdles work synergistically by disturbing the microbes' homeostasis. This technique is widely used in products like jam, fermented vegetables, meat, fish, and dairy. It improves safety and quality while reducing costs compared to using single preservation methods. However, some limitations exist in fully understanding and applying hurdle effects in practice.
Chilling and freezing are methods of food preservation that use low temperatures to slow microbial growth and chemical reactions in foods. Chilling involves storage between 0-15°C to extend shelf life by retarding bacteria, enzymes, and chemical changes. Freezing at below 0°C stops nearly all microbial and chemical changes by freezing water in foods into ice crystals. Quick freezing produces smaller ice crystals and less damage than slow freezing. Both methods maintain quality attributes better than other preservation methods, though texture changes can occur. Low temperature preservation is effective for long-term storage and retains more nutrients and sensory properties compared to other techniques.
Putrefaction is the anaerobic breakdown of proteins by microorganisms, producing foul-smelling compounds such as hydrogen sulfide and amines. It occurs when protein foods are broken down by proteolytic microorganisms into amino acids, ammonia, and hydrogen sulfide. Factors that affect putrefaction include the chemical composition and structure of food, temperature, pH, and the types of microorganisms present. Putrefaction can change the nutritional value, organoleptic properties, and safety of foods. Various foods are susceptible to putrefaction by different microorganisms if temperature abuse or lack of preservation methods allows the microbes to grow.
Water activity is a measure of available moisture in a food and is defined as the ratio of the water vapor pressure of the substance to the vapor pressure of pure water at the same temperature. Microbial growth and food spoilage is prevented when water activity is below 0.95. Various methods are used to control water activity and preserve foods, including drying, canning, freezing, and adding solutes or salt which lower available moisture content.
Proteins contribute significantly to the physical properties of foods, allowing them to build or stabilize gels, foams, doughs, emulsions, and fibrillar structures. Proteins act as foam-forming and foam-stabilizing agents by forming flexible films around gas bubbles that decrease surface tension. The stability of foams, emulsions, and gels depends on factors like the protein's ability to diffuse, denature, and associate at interfaces. Proteins can also increase viscosity, bind flavors, form dough networks, and exhibit antioxidant properties depending on their amino acid composition and structure.
Canning is a process that preserves food by heating it in hermetically sealed containers to kill microorganisms. It involves preparing and cutting meat into cubes, filling cans leaving headspace, exhausting air from cans then sealing them. The sealed cans are then thermally processed by heating to 121C for 1 hour to kill bacteria before rapidly cooling, washing, labeling, and lacquering the cans.
This document discusses methods of chilling fish to preserve quality. It describes wet icing as the most common chilling method, where ice is placed in direct contact with fish to draw heat away. Other methods include ice slurries, refrigerated air, dry ice, and gel ice mats. Proper chilling ensures fish is kept at 0-4°C to slow spoilage. Mechanical refrigerators and cryogenic systems are chilling equipment that uses refrigerants like ammonia or carbon dioxide to draw heat from fish. Insulation materials like polystyrene and polyurethane are used in containers to slow heat transfer and maintain temperature. Chilling preserves quality with minimal nutritional or textural effects on fish.
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
This document discusses water activity, which is a measure of the amount of free water available in a food product for microbial growth. It defines water activity as the ratio of vapor pressure of water in a food to the vapor pressure of pure water at the same temperature. Water activity, not water content, determines the lower limit for microbial growth. Most bacteria do not grow below a water activity of 0.91 and molds below 0.80. Measuring water activity allows prediction of spoilage and is important for controlling microbial growth, chemical reactions, and other quality factors in foods.
The document discusses the process of making protein isolates and concentrates from various sources such as soy, whey, peanuts, and fish. Protein isolates have a very high protein content (over 90%) and are refined to remove carbohydrates and fiber. Protein concentrates contain some carbohydrates and have a protein content over 80%. Common methods for extracting and purifying proteins include isoelectric precipitation, alkaline extraction, and ultrafiltration. Specific examples of production processes are provided for whey protein isolates, fish protein isolates, peanut protein isolates, and soy protein isolates and concentrates.
High pressure processing is a non-thermal food processing technique that uses high pressures, usually between 100-1000 MPa, to inactivate microorganisms and extend the shelf life of foods. It has minimal effects on taste, texture, color, and nutrients of foods. HPP is being used commercially for products like guacamole, sliced meats, seafood, juices, and dairy to kill pathogens and spoilage microbes while maintaining quality. The high pressure is applied uniformly from all directions using a pressure vessel filled with water, which compresses the packaged foods within minutes and safely destroys microbes without heat.
BAKERY AND CONFECTIONERY TECHNOLOGY notesMohit Jindal
This document provides an overview of the contents and topics covered in a course on Bakery and Confectionery Technology. The key topics discussed include:
- Raw materials used in bakery products like flour, sugar, shortening, yeast, and leavening agents. The roles and specifications of these raw materials are outlined.
- Manufacturing processes for various bakery products like bread, biscuits, cakes, and other products. Methods for preparation, quality evaluation, and causes of staling are addressed.
- Introduction to confectionery products, ingredients, and industry. Classification of confectionery and details about common sweeteners are provided.
- Layout, hygienic conditions,
Water plays an important role in food chemistry and can exist in different forms such as bound water (constitutional, vicinal, multilayer) and free water. The water activity (aw) of a food is related to its equilibrium relative humidity and influences properties like freezing point and reaction rates. Characterization techniques like sorption isotherms, dielectric measurements, NMR, and DSC can provide information about different types of water and how water interacts with the food matrix.
Water plays a key role in many aspects of food. It acts as a medium for chemical reactions, supports microbial growth, and contributes to texture. Removing or binding water through processes like drying, freezing, or adding salts/sugars can improve a food's shelf life by slowing reactions and microbial growth. The storage quality of food depends more on its water activity than its total water content. Decreasing water activity through drying, freezing, or adding humectants retards spoilage processes and microbial growth, improving shelf life. The physical state and phase transitions of foods containing water depend on temperature, composition, and water content.
This document describes an experiment to measure humidity using a psychrometer. It includes sections on the aim, introduction, theory, instructions, calculations, discussion, and references. The introduction explains that humidity is the amount of water vapor in air and defines relative humidity. The theory section describes how vapor pressure relates to temperature and humidity. The instructions explain how to use a psychrometer to measure the dry and wet bulb temperatures and determine relative humidity from a table.
Hurdle technology uses a combination of preservation methods to make foods shelf-stable while maintaining quality and safety. It involves using multiple hurdles like reduced moisture, increased acidity, refrigeration, or addition of preservatives that microorganisms must overcome to grow. The hurdles work synergistically so that microbes cannot adapt to or overcome all of the preservation factors simultaneously. This allows foods to be processed more gently and minimally while still achieving a long shelf life.
Blanching is a heat treatment of fruits and vegetables that inactivates enzymes and microorganisms. It involves rapidly heating produce to a specified temperature for a short time period, then rapidly cooling it. This helps prevent quality degradation during further processing like freezing, canning, or drying by stopping enzymatic and microbial activity. Blanching also softens tissues, removes gases, and helps with peeling or packaging of produce. However, it can result in some nutrient and texture loss depending on the time-temperature combination used.
Non thermal process in preservation of foodGazanfar Abass
The document discusses various non-thermal food processing techniques as alternatives to traditional thermal processing. It provides examples of different non-thermal methods like pulsed electric field, high pressure processing, pulsed light technology, microwave heating, ohmic heating, and irradiation. These methods aim to increase production rates and profits for food industries while maintaining better quality, nutrients, flavor and extending shelf life compared to thermal processing which can result in loss of volatile compounds. The non-thermal methods are particularly suitable for large scale and liquid food production.
The document discusses the functional properties of proteins in foods. It begins by defining functionality as any non-nutritive property that influences an ingredient's usefulness. It then identifies three main groups of functional properties: hydration properties related to protein-water interactions like solubility and viscosity; properties related to protein-protein interactions like gelation and dough formation; and surface properties involved in emulsification and foaming. Specific examples covered include the role of proteins in viscosity, gelation, emulsions, foams, and dough formation. The document concludes by noting how extrusion and enzymatic hydrolysis can alter soy protein properties.
Baking and roasting are similar processes that use heated air to alter the quality of foods. Baking is typically used for flour-based foods and fruits, while roasting is for meats, nuts and vegetables. Both processes involve heat transfer through radiation, convection and conduction to cook foods internally without exceeding 100°C. This causes surface changes that improve qualities like moisture retention. Ovens can be direct or indirect heating types, and batch, continuous or semi-continuous systems. Frying methods include deep frying by full submersion in hot oil, shallow frying with partial submersion, and stir frying using minimal oil. Frying oils undergo hydrolysis and oxidation over time, producing compounds that degrade quality
This document discusses intermediate moisture foods (IMF), which are foods with a water activity between 0.6-0.9 that prevents microbial growth. Examples include jams, jellies, candies, baked goods, honey, and dried meats. IMF have 10-50% moisture. Water activity measures the availability of water for microbial growth. IMF provide food preservation by controlling water activity and may include additional preservatives. While IMF don't require refrigeration, they can contain high sugar or salt and their texture may deteriorate if not properly handled.
Hurdle technology involves using two or more preservation methods together to inhibit microbial spoilage of foods. It allows for safer, stable foods without refrigeration. Common hurdles include reduced pH, increased salt content, reduced water activity, and heat processing. The hurdles work synergistically by disturbing the microbes' homeostasis. This technique is widely used in products like jam, fermented vegetables, meat, fish, and dairy. It improves safety and quality while reducing costs compared to using single preservation methods. However, some limitations exist in fully understanding and applying hurdle effects in practice.
Chilling and freezing are methods of food preservation that use low temperatures to slow microbial growth and chemical reactions in foods. Chilling involves storage between 0-15°C to extend shelf life by retarding bacteria, enzymes, and chemical changes. Freezing at below 0°C stops nearly all microbial and chemical changes by freezing water in foods into ice crystals. Quick freezing produces smaller ice crystals and less damage than slow freezing. Both methods maintain quality attributes better than other preservation methods, though texture changes can occur. Low temperature preservation is effective for long-term storage and retains more nutrients and sensory properties compared to other techniques.
Putrefaction is the anaerobic breakdown of proteins by microorganisms, producing foul-smelling compounds such as hydrogen sulfide and amines. It occurs when protein foods are broken down by proteolytic microorganisms into amino acids, ammonia, and hydrogen sulfide. Factors that affect putrefaction include the chemical composition and structure of food, temperature, pH, and the types of microorganisms present. Putrefaction can change the nutritional value, organoleptic properties, and safety of foods. Various foods are susceptible to putrefaction by different microorganisms if temperature abuse or lack of preservation methods allows the microbes to grow.
Water activity is a measure of available moisture in a food and is defined as the ratio of the water vapor pressure of the substance to the vapor pressure of pure water at the same temperature. Microbial growth and food spoilage is prevented when water activity is below 0.95. Various methods are used to control water activity and preserve foods, including drying, canning, freezing, and adding solutes or salt which lower available moisture content.
Proteins contribute significantly to the physical properties of foods, allowing them to build or stabilize gels, foams, doughs, emulsions, and fibrillar structures. Proteins act as foam-forming and foam-stabilizing agents by forming flexible films around gas bubbles that decrease surface tension. The stability of foams, emulsions, and gels depends on factors like the protein's ability to diffuse, denature, and associate at interfaces. Proteins can also increase viscosity, bind flavors, form dough networks, and exhibit antioxidant properties depending on their amino acid composition and structure.
Canning is a process that preserves food by heating it in hermetically sealed containers to kill microorganisms. It involves preparing and cutting meat into cubes, filling cans leaving headspace, exhausting air from cans then sealing them. The sealed cans are then thermally processed by heating to 121C for 1 hour to kill bacteria before rapidly cooling, washing, labeling, and lacquering the cans.
This document discusses methods of chilling fish to preserve quality. It describes wet icing as the most common chilling method, where ice is placed in direct contact with fish to draw heat away. Other methods include ice slurries, refrigerated air, dry ice, and gel ice mats. Proper chilling ensures fish is kept at 0-4°C to slow spoilage. Mechanical refrigerators and cryogenic systems are chilling equipment that uses refrigerants like ammonia or carbon dioxide to draw heat from fish. Insulation materials like polystyrene and polyurethane are used in containers to slow heat transfer and maintain temperature. Chilling preserves quality with minimal nutritional or textural effects on fish.
This document provides an overview of high pressure processing (HPP) of foods. HPP uses high pressure, around 400-600 MPa, to inactivate pathogens and microorganisms while minimally affecting the food's qualities. HPP retains food quality by preserving nutrients, texture, taste and appearance. It has applications for foods like meats, seafood, juices, sauces, dairy products and more. The advantages of HPP are that it achieves uniform microbial reduction without heat, maintains sensory qualities and is more environmentally friendly than thermal processing. The document discusses the basic principles, history, equipment, generation of pressure, applications and advantages and disadvantages of HPP.
This document discusses water activity, which is a measure of the amount of free water available in a food product for microbial growth. It defines water activity as the ratio of vapor pressure of water in a food to the vapor pressure of pure water at the same temperature. Water activity, not water content, determines the lower limit for microbial growth. Most bacteria do not grow below a water activity of 0.91 and molds below 0.80. Measuring water activity allows prediction of spoilage and is important for controlling microbial growth, chemical reactions, and other quality factors in foods.
The document discusses the process of making protein isolates and concentrates from various sources such as soy, whey, peanuts, and fish. Protein isolates have a very high protein content (over 90%) and are refined to remove carbohydrates and fiber. Protein concentrates contain some carbohydrates and have a protein content over 80%. Common methods for extracting and purifying proteins include isoelectric precipitation, alkaline extraction, and ultrafiltration. Specific examples of production processes are provided for whey protein isolates, fish protein isolates, peanut protein isolates, and soy protein isolates and concentrates.
High pressure processing is a non-thermal food processing technique that uses high pressures, usually between 100-1000 MPa, to inactivate microorganisms and extend the shelf life of foods. It has minimal effects on taste, texture, color, and nutrients of foods. HPP is being used commercially for products like guacamole, sliced meats, seafood, juices, and dairy to kill pathogens and spoilage microbes while maintaining quality. The high pressure is applied uniformly from all directions using a pressure vessel filled with water, which compresses the packaged foods within minutes and safely destroys microbes without heat.
BAKERY AND CONFECTIONERY TECHNOLOGY notesMohit Jindal
This document provides an overview of the contents and topics covered in a course on Bakery and Confectionery Technology. The key topics discussed include:
- Raw materials used in bakery products like flour, sugar, shortening, yeast, and leavening agents. The roles and specifications of these raw materials are outlined.
- Manufacturing processes for various bakery products like bread, biscuits, cakes, and other products. Methods for preparation, quality evaluation, and causes of staling are addressed.
- Introduction to confectionery products, ingredients, and industry. Classification of confectionery and details about common sweeteners are provided.
- Layout, hygienic conditions,
Water plays an important role in food chemistry and can exist in different forms such as bound water (constitutional, vicinal, multilayer) and free water. The water activity (aw) of a food is related to its equilibrium relative humidity and influences properties like freezing point and reaction rates. Characterization techniques like sorption isotherms, dielectric measurements, NMR, and DSC can provide information about different types of water and how water interacts with the food matrix.
Water plays a key role in many aspects of food. It acts as a medium for chemical reactions, supports microbial growth, and contributes to texture. Removing or binding water through processes like drying, freezing, or adding salts/sugars can improve a food's shelf life by slowing reactions and microbial growth. The storage quality of food depends more on its water activity than its total water content. Decreasing water activity through drying, freezing, or adding humectants retards spoilage processes and microbial growth, improving shelf life. The physical state and phase transitions of foods containing water depend on temperature, composition, and water content.
This document describes an experiment to measure humidity using a psychrometer. It includes sections on the aim, introduction, theory, instructions, calculations, discussion, and references. The introduction explains that humidity is the amount of water vapor in air and defines relative humidity. The theory section describes how vapor pressure relates to temperature and humidity. The instructions explain how to use a psychrometer to measure the dry and wet bulb temperatures and determine relative humidity from a table.
Water activity, not moisture content, determines the lower limit of “available” water for microbial growth. Since bacteria, yeast, and molds require a certain amount of “available” water to support growth, designing a product below a critical water activity level provides an effective means to control growth.
The experiment examined pressure drop across a packed column as a function of air and water flow rates. Pressure drop increased with higher flow rates of both air and water. The relationship between log pressure drop and log air flow rate was plotted, showing they follow the same trend as theoretical predictions. Pressure drop rose sharply before a "flooding point" where liquid accumulated and filled the column.
1. Humidity refers to the amount of water vapor present in the air. Relative humidity is the percentage of water vapor in the air relative to the maximum amount that could be held at a given temperature.
2. A hygrometer is an instrument used to measure humidity. Common types include hair hygrometers, which use the hygroscopic property of human hair to expand and contract based on humidity levels.
3. Hair hygrometers work by arranging human hairs in parallel beams under tension. When humidity increases, the hairs absorb moisture and expand, moving an attached pointer along a calibrated scale to indicate the relative humidity percentage. They are inexpensive but slow-responding.
This document provides information about different types of solutions and their properties. It discusses true solutions as homogeneous mixtures containing a solute dissolved in a solvent. Properties like vapor pressure lowering and boiling/freezing point changes depend on solute concentration and are known as colligative properties. Osmotic pressure, the pressure required to stop osmosis across a semipermeable membrane, can be calculated using Van't Hoff's equation and depends on solute molarity. Solutions can also be classified as hypotonic, hypertonic, or isotonic based on their solute concentrations.
Factors affecting microbial growth in food can be intrinsic, related to characteristics of the food itself, or extrinsic, related to external environmental conditions. Intrinsic factors include pH, water activity, nutrients, and antimicrobial contents. pH and water activity are especially important as most bacteria grow between pH 6.8-7.5 and require a minimum water activity of 0.91. Controlling the pH and water activity of foods through methods like fermentation, addition of acids or salts, and moisture reduction can inhibit microbial growth and improve food stability.
This document discusses capillary pressure concepts including:
1) Capillary pressure is the pressure difference between two immiscible fluids separated by an interface, usually calculated as the pressure difference between the non-wetting and wetting phases.
2) Capillary pressure curves show the relationship between fluid saturation and height above the free water level, with the drainage curve always higher than the imbibition curve.
3) Displacement or entry pressure is the pressure required to force the non-wetting fluid through an initially wetting-phase saturated sample.
Capillary pressure data can be used to determine initial fluid saturations, fluid distributions in reservoirs, and residual oil saturations. It is related to properties like pore size, wettability, interfacial tension, and fluid densities. Capillary pressure curves show hysteresis between drainage and imbibition processes. Laboratory data must be converted to reservoir conditions using equations accounting for property differences. The J-function can average capillary pressure data for a given rock type.
Animal physiology vapour and solubility of gasesDrNagabhushanCM
This document discusses water vapour in air and the solubility of gases. It provides a table showing how the pressure and percentage of water vapour in air increases with rising temperature. The solubility of gases like oxygen, nitrogen, and carbon dioxide are also detailed. Key points made include how water vapour pressure increases with temperature, affecting boiling points. It also examines how gas solubility is affected by pressure, temperature, and other dissolved substances based on Henry's law.
Water activity is a measure of the energy status of water in a system. It is defined as the ratio of the vapor pressure of water in a substance to the vapor pressure of pure water at the same temperature. Water activity is dependent on temperature and influences processes like microbial growth and moisture migration. It can be controlled through formulation strategies like reducing moisture content, blending ingredients with different water activities, or using excipients to bind water and lower the overall water activity at a given moisture level. Measuring and modeling a substance's sorption isotherm provides information to understand and manipulate its water binding properties and water activity profile.
Distillation MSG.ppt for B.Pharmacy SEM-III Pharmaceutical EngineeringStudy m...Mahesh Gadge
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities. It involves heating the mixture to vaporize components, cooling the vapors to condense them, and collecting the condensed liquids. There are several types of distillation including simple distillation, flash distillation, and vacuum distillation. Simple distillation is used to separate components with very different boiling points, while flash distillation and vacuum distillation can separate components with closer boiling points. Distillation has many applications in industries like petroleum refining, organic chemical purification, and extracting essential oils from plants.
Absolute humidity measures the amount of water vapor in the air regardless of temperature, while relative humidity measures water vapor relative to the air's temperature. Warm air can hold more moisture than cold air. Maintaining an indoor relative humidity of 40-60% is optimal for health and comfort, as too much or too little humidity can cause issues. A Zehnder Enthalpy Exchanger recovers both thermal and humidity energy from extracted stale air and transfers it to incoming fresh air, helping maintain comfortable moisture levels in the home.
Water activity (aw) is defined as the ratio of the vapor pressure of water in a food to the vapor pressure of pure water at the same temperature. It indicates how available the water is in a food for microbial growth and chemical reactions. Most bacteria do not grow below an aw of 0.91 and molds below 0.80, while S. aureus can grow down to 0.86. Measuring aw can predict spoilage and determine enzyme and vitamin activity in foods. Stability depends on both aw and pH. Common methods to control aw include drying, adding salt or sugar, and freezing.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
This document provides an overview of analytical methods for measuring acidity in foods, including titratable acidity and pH. It discusses:
- Titratable acidity measures total acid concentration through exhaustive titration with a standard base, while pH quantifies only free H3O+ concentration.
- pH is a logarithmic scale that can range from 0-14, representing hydrogen ion concentrations that span 14 orders of magnitude.
- The relationship between pH, H3O+ concentration, and water's ion product constant (Kw) determines pH in solutions.
- Acid ratios like Brix/acid are better indicators of acid impact on flavor than measurements of acidity or Brix alone, as
Water activity is a measure of how available water is in a food system for microbial growth. It is defined as the vapor pressure of water in a food divided by the vapor pressure of pure water at the same temperature. Measurement techniques include vapor pressure measurement using a manometer, freezing point depression, psychrometry using hygrometers or thermocouples, isopiestic transfer between materials, and measuring matric or suction potential in gels. Choice of technique depends on required range, accuracy, precision and speed needed.
Water quality index with missing parameterseSAT Journals
Abstract This paper presents the efficient modifications in calculating formula of water quality index. Water quality index provides us a single number which expresses overall water quality at a certain location and time which is based on several quality parameters. The objective of an index is to turn complex water quality data into information that is understandable and usable by the public. In this paper a formula will be found to calculate water quality index when the numerical value of some of it’s quality parameters are missing. The standard formula to calculate water quality index has nine water quality parameters- biochemical oxygen demand, dissolved oxygen, pH, nitrate, phosphate, faecal coliform, turbidity, total dissolve solids and temperature. Sometimes it becomes very difficult to find out the values of all these parameters because of lack of time or because of failure in testing. In that case the formula with missing parameters will help us to calculate water quality index. Index Terms: Water quality index, q- values, weight factors, weighted mean.
The basic food law is intended to assure consumers that foods are pure and wholesome, safe to eat, and produced under sanitary conditions. Generally, food law prohibits importation and distribution of food products that are adulterated, or have labels that are false or misleading in any context.
Soil and water conditions. ...
Keep an eye on the forecast for heavy rainfall events. ...
Calibrate, inspect, and maintain manure application equipment. ...
Separation distances for land application. ...
Irrigation of manure sources. ...
Savvy stockpiling and dry manure management.
Based on the mode of action, the major food preservation techniques can be categorized as: (1) slowing down or inhibiting chemical deterioration and microbial growth, (2) directly inactivating bacteria, yeasts, molds, or enzymes, and (3) avoiding recontamination before and after processing.
Food processing waste is derived from the processing of biological materials and is, in the main, biodegradable. Biowaste is defined in the landfill directive as 'waste capable of undergoing anaerobic or aerobic decomposition such as food and garden waste, and paper and cardboard
Water plays a key role in food processing and has various scientific uses. It acts as a solvent, carrier, and lubricant in processes like washing, leaching, extraction, and cooling. Proper management and treatment of water is important for food safety and quality in processing plants.
The environmental damage of food production from conventional agriculture is not limited to deforestation and pollutants associated with crop growth. Harvesting the crop represents a significant amount of nutrients, water, and energy being taken from the land.
The basis for sanitation is the removal of soils from the manufacturing environment. There are many benefits to this process. From a food safety standpoint, there is the removal of pathogenic organisms, prevention of the formation of biofilms and removal of potentially harmful chemicals from food contact surfaces.
Food packaging is defined as enclosing food to protect it from tampering or contamination from physical, chemical, and biological sources, with active packaging being the most common packaging system used for preserving food products.
Sugar, salt, nitrites, butylated hydroxy anisol (BHA), butylated hydroxyl toluene (BHT), tert-butylhydroquinone (TBHQ), vinegar, citric acid, and calcium propionate are all chemicals that preserve foods. Salt, sodium nitrite, spices, vinegar, and alcohol have been used to preserve foods for centuries.
Sugaring is a food preservation method similar to pickling. Sugaring is the process of desiccating a food by first dehydrating it, then packing it with pure sugar. This sugar can be crystalline in the form of table or raw sugar, or it can be a high sugar density liquid such as honey, syrup or molasses.
Removing the moisture from food helps prevent bacterial and fungal growth which would ruin stored foods. Smoking is a method of drying that also imparts flavor to the food (usually meat items), and smoke helps keep bacteria-carrying-insects away during the drying process.
Microwave penetrates inside the food materials resulting in entire internal cooking of whole volume of food rapidly and uniformly reducing the processing time and energy. This fast heat transfer in turn results in preservation of nutrients, vitamins contents, flavor, sensory characteristics, and color of food
Food irradiation (the application of ionizing radiation to food) is a technology that improves the safety and extends the shelf life of foods by reducing or eliminating microorganisms and insects. Like pasteurizing milk and canning fruits and vegetables, irradiation can make food safer for the consumer
Food irradiation is the process of exposing food and food packaging to ionizing radiation, such as from gamma rays, x-rays, or electron beams. Wikipedia
Low dose (up to 1 kGy): Inhibit sprouting (potatoes, onions, yams, garlic)
Lowering the temperature of food so that microbes and enzymes are inactivated.
Moisture is changed to ice and microbes become inactive without water.
Packaging food maintains the colour, flavour and texture.
Fast freezing (-25ºC) helps maintain nutritive value and texture of food.
Chilling is an important activity in food processing. Foods are chilled to extend shelf life by reducing biochemical reactions and microbial activity. Temperature control is essential in order to prevent spoilage and food safety concerns during storage.1
Drying is a mass transfer process consisting of the removal of water or another solvent by evaporation from a solid, semi-solid or liquid. This process is often used as a final production step before selling or packaging products.
Food drying is a method of food preservation in which food is dried (dehydrated or desiccated). Drying inhibits the growth of bacteria, yeasts, and mold through the removal of water.
Dehydration has been used widely for this purpose since ancient times; the earliest known practice is 12,000 B.C. by inhabitants of the modern Middle East and Asia regions. Drying is a simple method for preserving food.
Dried foods make great healthy and tasty snacks. They are good for lunches, travel, backpacking, hiking, and camping plus many other activities. Most types of foods can be dried. Drying is an ancient method of food preservation.
Most foods will not support the growth of bacteria if their water activity is less than 0.85, because at this water activity there is not enough water available for the bacteria to grow.
However, yeasts can grow at water activities as low as 0.70, while some molds will grow even at water activities as low as 0.60!
Foods with water activities in this range usually have preservatives added to prevent the growth of yeasts and molds.
Acidic foods with a pH less than 4.6, such as tomato sauce, retard the growth of microorganisms. Thus an acidic food with a water activity less than 0.85 is relatively shelf stable, especially if it is stored in the refrigerator.
In this case, low pH, water activity and temperature combine to provide good insurance against the growth of harmful pathogens.
Sorption is a physical and chemical process by which one substance becomes attached to another.
Sorption includes both adsorption & absorption
e.g., liquids being absorbed by a solid or gases being absorbed by a liquid, cotton dipped in ink.
Sorption the process in which one substance takes up or holds another; adsorption or absorption
Sorption is a process in which a solute moves from a fluid to a particulate solid.
The food sorption isotherm describes the thermodynamic relationship between water activity and the equilibrium of the moisture content of a food product at constant temperature and pressure. ...
The typical shape of an isotherm reflects the way in which the water binds the system.
Water plays many very important roles in food. It affects texture (dry and brittle versus moist and soft), enables the activity of enzymes and chemical reactions to occur (acts as a solvent), supports the growth of microorganisms, makes it possible for large molecules like polysaccharides and proteins to move about and interact, and conducts heat within food.
Many foods such as meat, poultry, seafood, fruits and vegetables are composed of 75% and more water, so water is the most abundant component in many fresh foods. Other foods such as dairy products, and fresh baked goods also contain high levels of water (about 35% or more). Foods that are high in moisture are at
risk of contamination from the growth of microorganisms such as bacteria, yeast and mold, while dry foods like pasta generally have long shelf lives.
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
ABSTRACT: A prima vista, un mattoncino Lego e la backdoor XZ potrebbero avere in comune il fatto di essere entrambi blocchi di costruzione, o dipendenze di progetti creativi e software. La realtà è che un mattoncino Lego e il caso della backdoor XZ hanno molto di più di tutto ciò in comune.
Partecipate alla presentazione per immergervi in una storia di interoperabilità, standard e formati aperti, per poi discutere del ruolo importante che i contributori hanno in una comunità open source sostenibile.
BIO: Sostenitrice del software libero e dei formati standard e aperti. È stata un membro attivo dei progetti Fedora e openSUSE e ha co-fondato l'Associazione LibreItalia dove è stata coinvolta in diversi eventi, migrazioni e formazione relativi a LibreOffice. In precedenza ha lavorato a migrazioni e corsi di formazione su LibreOffice per diverse amministrazioni pubbliche e privati. Da gennaio 2020 lavora in SUSE come Software Release Engineer per Uyuni e SUSE Manager e quando non segue la sua passione per i computer e per Geeko coltiva la sua curiosità per l'astronomia (da cui deriva il suo nickname deneb_alpha).
Salesforce Integration for Bonterra Impact Management (fka Social Solutions A...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on integration of Salesforce with Bonterra Impact Management.
Interested in deploying an integration with Salesforce for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
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Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Have you ever been confused by the myriad of choices offered by AWS for hosting a website or an API?
Lambda, Elastic Beanstalk, Lightsail, Amplify, S3 (and more!) can each host websites + APIs. But which one should we choose?
Which one is cheapest? Which one is fastest? Which one will scale to meet our needs?
Join me in this session as we dive into each AWS hosting service to determine which one is best for your scenario and explain why!
Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
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Key Topics Covered
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- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
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5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
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TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
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Webinar: Designing a schema for a Data WarehouseFederico Razzoli
Are you new to data warehouses (DWH)? Do you need to check whether your data warehouse follows the best practices for a good design? In both cases, this webinar is for you.
A data warehouse is a central relational database that contains all measurements about a business or an organisation. This data comes from a variety of heterogeneous data sources, which includes databases of any type that back the applications used by the company, data files exported by some applications, or APIs provided by internal or external services.
But designing a data warehouse correctly is a hard task, which requires gathering information about the business processes that need to be analysed in the first place. These processes must be translated into so-called star schemas, which means, denormalised databases where each table represents a dimension or facts.
We will discuss these topics:
- How to gather information about a business;
- Understanding dictionaries and how to identify business entities;
- Dimensions and facts;
- Setting a table granularity;
- Types of facts;
- Types of dimensions;
- Snowflakes and how to avoid them;
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HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
GraphRAG for Life Science to increase LLM accuracyTomaz Bratanic
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2. CONTENTS
Introduction
Definitions
Definitions
Concept of Water Activity
Why Water Activity is important?
Methods for measuring water activity
Factors affecting Water Activity
Microbial Growth of aw
Minimum aw for some bacterial growth
Examples of aw values of several foods
Advantages & Disadvantages of aw
3. •Most foods will not support the growth of bacteria if their water activity is less than 0.85, because at this water
activitythereisnot enoughwateravailableforthebacteriato grow.
•However, yeasts can grow at water activities as low as 0.70, while some molds will grow even at water activities
aslowas 0.60!
•Foods with water activities in this range usually have preservatives added to prevent the growth of yeasts and
molds.
•Acidic foods with a pH less than 4.6, such as tomato sauce, retard the growth of microorganisms. Thus an
acidic food with a water activity less than 0.85 is relatively shelf stable, especially if it is stored in the
refrigerator.
•In this case, low pH, water activity and temperature combine to provide good insurance against the growth of
harmfulpathogens.
Introduction
4. Definitions
Food scientists measure the amount of water that is available for the growth of microorganisms, as well as
enzymeandchemicalreactions,througha numberknownas wateractivity(aW).
Water activity is a measure of the amount of free and adsorbed water in food, and is measured on a
dimensionlessscaleof zeroto one.
Water activity is the ratio of the vapor pressure (P) of water in food divided by the vapor pressure of pure
water(P0)at thesametemperature.
Thewateractivityof purewaterisequalto 1.0.
Another way of determining water activity is by measuring the relative humidity (RH) of the atmosphere in
equilibriumwiththefood:RH (%)= 100 x aW.
5. Food Moisture% Water Activity
Fresh meat 70 0.98
Bread 40 0.95
Flour 14 0.70
Pasta 10 0.45
Potato chips 2 0.10
Inotherwords,wateractivityisa measureof thewaterthatis availableto be convertedto vapor.
Thereis a generalcorrelationof themoisturecontentof foodwithitswateractivity, asshowninthe table
below.
6. Conceptof WATERACTIVITY
The concept of aw has been very useful in food preservation
and on that basis many processes could be successfully adapted
and new products designed.
Water has been called the universal solvent as it is a
requirement for growth, metabolism, and support of many
chemical reactions occurring in food products.
Free water in fruit or vegetables is the water available for
chemical reactions, to support microbial growth, and to act as a
transporting medium for compounds.
In the bound state, water is not available to participate in
these reactions as it is bound by water soluble compounds such
as sugar, salt, gums, etc. (osmotic binding), and by the surface
effect of the substrate (matrix binding).
These water-binding effects reduce the vapour pressure of the
food substrate according to Raoult’s Law.
7. Comparing this vapour pressure with that of pure water (at the
same temperature) results in a ratio called water activity (aw).
Pure water has an aw of 1, one molal solution of sugar - 0.98,
and one molal solution of sodium chloride - 0.9669.
A saturated solution of sodium chloride has a water activity of
0.755. This same NaCl solution in a closed container will develop
an equilibrium relative humidity (ERH) in a head space of 75.5%.
A relationship therefore exists between ERH and aw since both
are based on vapour pressure.
The ERH of a food product is defined as the relative humidity of
the air surrounding the food at which the product neither gains nor
loses its natural moisture and is in equilibrium with the
environment.
aw=ERH
100
8.
9.
10.
11.
12.
13. Why is water activity important?
Water activity is a critical factor that determines shelf life.
While temperature, pH and several other factors can influence if
and how fast organisms will grow in a product, water activity may
be the most important factor in controlling spoilage.
Most bacteria, for example, do not grow at water activities
below 0.91, and most molds cease to grow at water activities
below 0.80.
By measuring water activity, it is possible to predict which
microorganisms will and will not be potential sources of spoilage.
14. Water activity--not water content--determines the lower limit
of available water for microbial growth.
In addition to influencing microbial spoilage, water activity can
play a significant role in determining the activity of enzymes and
vitamins in foods and can have a major impact their color, taste,
and aroma.
It can also significantly impact the potency and consistency of
pharmaceuticals.
15. METHODSFORMEASURINGWATERACTIVITY
Methods are based on the colligative properties of solutions.
Water activity can be estimated by measuring the following:
1. Vapour pressure
2. Osmotic pressure
3. Freezing point depression of a liquid
4. Equilibrium relative humidity of a liquid or solid
5. Boiling point elevation
6. Dew point and wet bulb depression
7. Suction potential, or by using the isopiestic method
8. Bithermal equilibrium
9. Electric hygrometers
10. Hair hygrometers
16. Water activity is expressed as the ratio of the partial pressure of
water in a food to the vapour pressure of pure water with the
same temperature as the food.
Thus, measuring the vapour pressure of water in a food system is
the most direct measure of aw.
The food sample measured is allowed to equilibrate, and
measurement is taken by using a manometer or transducer device
(Vapour pressure manometer).
This method can be affected by sample size, equilibration time,
temperature, and volume.
This method is not suitable for biological materials with active
respiration or materials containing large amounts of Volatiles.
1. Vapourpressure
17.
18. 2. Osmotic pressure
Water activity can be related to the osmotic pressure (p) of a solution
with the following equation:
p = RT/Vw ln(aw)
where Vw is the molar volume of water in solution, R the universal gas
constant, and T the absolute temperature.
Osmotic pressure is defined as the mechanical pressure needed to prevent
a net flow of solvent across a semi-permeable membrane. For an ideal
solution, Equation can be redefined as:
p = RT/Vw ln(Xw)
where Xw is the molar fraction of water in the solution. For non-ideal
solutions, the osmotic pressure expression can be rewritten as:
p = RTfnmb(mwVw)
where n is the number of moles of ions formed from one mole of
electrolyte, mw and mb are the molar concentrations of water and the
solute, respectively, and f the osmotic coefficient, defined as:
f = -mw ln(aw)/nmb
19.
20. 3. Freezing point depression of a liquid
This method is accurate for liquids in the high water activity range but is
not suitable for solid foods (Barbosa-Cánovas and Vega-Mercado, 1996).
The water activity can be estimated using the following two expressions:
Freezing point depression:
-log aw = 0.004207 DTf + 2.1 E-6 DT2
f (1)
where DTf is the depression in the freezing temperature of water
Boiling point elevation:
-log aw = 0.01526 DTb - 4.862 E-5 DT2
b (2)
where DTb is the elevation in the boiling temperature of water.
21. 4. Equilibriumrelativehumidityof a liquidor solid
The relative humidity is the water vapor pressure (numerator) divided
by the equilibrium vapor pressure (denomator) times 100%. The
equilibrium vapor pressure occurs when there is an equal
(thus the word equilibrium) flow of water molecules
arriving and leaving the condensed phase (the liquid or ice).
If the water vapor pressure is greater than the equilibrium value
(numerator is greater), there is a net condensation (and a cloud could
form, say).
And that is not because the air cannot hold the water, but merely
because there is a greater flow into the condensed phase than out of it.
Relative humidity describes the amount of water vapor actually in the
air (numerator), relative to the maximum amount of water the air can
possibly hold for a given temperature (denominator).
22. One important consequence is that when air masses change in temperature,
the relative humidity can change, even if the actual amount of water vapor
in the air does not (the numerator in our equation, which is defined by the
saturation curve, stays the same, but the denominator changes with
temperature).
If the relative humidity (RH) is 100%, this means that condensation
would occur. On a typical hot muggy summer day, RH might be around
60-80%. In a desert, RH is commonly around 15-25%.
It is expressed as a percentage:
RH=H2OactualH2OmaxThis equation is not rendering properly due to an
incompatible browser. See Technical Requirements in the Orientation for a
list of compatible browsers.
23. When an air mass contains the maximum amount of water it can hold, it is
saturated with water vapor. This is shown graphically in the plot above as
the black solid curved line in Figure .With increasing temperature (x-axis),
the air can hold more water vapor (y-axis), as indicated by higher
saturation values (solid black curved line).
In general, it is not possible to have water contents that exceed
saturation (i.e. relative humidity is 100%). In other words, the maximum
relative humidity is generally not greater than 100% (i.e. not above the
solid black curved line). Another way to think about relative humidity is
that it describes how close the air is to saturation.
In the example shown, the actual water vapor content is about 40% of
that at saturation (i.e. the blue point is about 40% of the way to
saturation) – meaning the RH = 40%.
24.
25.
26.
27. 5. Boilingpointelevation
oBoiling-point elevation describes the phenomenon that the boiling point of
a liquid will be higher when another compound is added, meaning that a
solution has a higher boiling point than a pure solvent.
oThis happens whenever a non-volatile solute, such as a salt, is added to
a pure solvent, such as water.
oThe boiling point elevation is a colligative property, which means that it
is dependent on the presence of dissolved particles and their number,
but not their identity.
oIt is an effect of the dilution of the solvent in the presence of a
solute.
oIt is a phenomenon that happens for all solutes in all solutions, even in
ideal solutions, and does not depend on any specific solute–solvent
interactions.
oThe boiling point elevation happens both when the solute is
an electrolyte, such as various salts, and a nonelectrolyte.
28. In thermodynamic terms, the origin of the boiling point elevation
is entropic and can be explained in terms of the vapor
pressure or chemical potential of the solvent.
In both cases, the explanation depends on the fact that many solutes are
only present in the liquid phase and do not enter into the gas phase
(except at extremely high temperatures).
Put in vapor pressure terms, a liquid boils at the temperature when its
vapor pressure equals the surrounding pressure.
For the solvent, the presence of the solute decreases its vapor pressure
by dilution.
A nonvolatile solute has a vapor pressure of zero, so the vapor pressure
of the solution is less than the vapor pressure of the solvent.
Thus, a higher temperature is needed for the vapor pressure to reach
the surrounding pressure, and the boiling point is elevated.
29. Put in chemical potential terms, at the boiling point, the liquid phase and
the gas (or vapor) phase have the same chemical potential (or vapor
pressure) meaning that they are energetically equivalent.
The chemical potential is dependent on the temperature, and at other
temperatures either the liquid or the gas phase has a lower chemical
potential and is more energetically favorable than the other phase.
This means that when a nonvolatile solute is added, the chemical
potential of the solvent in the liquid phase is decreased by dilution, but
the chemical potential of the solvent in the gas phase is not affected.
This means in turn that the equilibrium between the liquid and gas phase
is established at another temperature for a solution than a pure liquid,
i.e., the boiling point is elevated.
30. The phenomenon of freezing-point depression is analogous to boiling point
elevation.
However, the magnitude of the freezing point depression is larger than
the boiling point elevation for the same solvent and the same
concentration of a solute.
Because of these two phenomena, the liquid range of a solvent is
increased in the presence of a solute.
The extent of boiling-point elevation can be calculated by
applying Clausius–Clapeyron relation and Raoult's law together with the
assumption of the non-volatility of the solute.
The result is that in dilute ideal solutions, the extent of boiling-point
elevation is directly proportional to the molal concentration (amount of
substance per mass) of the solution according to the equation:
ΔTb = Kb · bB
where the boiling point elevation, is defined as
Tb (solution) - Tb (pure solvent).
31. Kb, the ebullioscopic constant, which is dependent on the properties of the
solvent. It can be calculated as Kb = RTb
2M/ΔHv,
where R is the gas constant, and Tb is the boiling temperature of the pure
solvent [in K], M is the molar mass of the solvent, and ΔHv is the heat of
vaporization per mole of the solvent.
bB is the molality of the solution, calculated by taking dissociation into
account since the boiling point elevation is a colligative property, dependent
on the number of particles in solution.
This is most easily done by using the van 't Hoff factor i as bB = bsolute · i. The
factor i accounts for the number of individual particles (typically ions) formed
by a compound in solution.
32. 6. Dewpointandwetbulbdepression
For warmer temperatures than 60, the cooling is between about 1/3
and 1/2 the dew-point depression.
If the temperature was 42 with a dew-point of 15 and it started
raining, the temperature and dew-point would wet-bulb out to a chilly
33 degrees Fahrenheit.
A quick technique that many forecasters use to determine the wet-bulb
temperature is called the "1/3 rule".
The technique is to first find the dew-point depression (temperature
minus dew-point).
Then take this number and divide by 3. Subtract this number from the
temperature. You now have an approximation for the wet-bulb
temperature.
33. Vapour pressure can be determined from the dew point of an air-water
mixture.
The temperature at which the dew point occurs is determined by
observing condensation on a smooth, cool surface such as a mirror.
This temperature can be related to vapour pressure using a
psychrometric chart.
The formation of dew is detected photoelectrically
Suppose the temperature is 42 degrees Fahrenheit with a dew-point of
15 degrees Fahrenheit.
The dew-point depression is 42-15 = 27. Now divide 27 by 3 = 9. Now
subtract 9 from the original temperature of 42. 42 - 9 = 33.
For temperatures between 30 and 60 degrees F, the 1/3 rule works
quite well.
For warmer temperatures than 60, the cooling is between about 1/3
and 1/2 the dew-point depression.
34. If the temperature was 42 with a dew-point of 15 and it started raining,
the temperature and dew-point would wet-bulb out to a chilly 33 degrees
Fahrenheit.
As dew-point depression or temperature increase, the evaporation
potentialincreases.
This technique does not give the exact wet bulb temperature but it does
give a pretty close approximation.
Warmer air will cool at a greater rate than colder air since more water
vapor can evaporate into warm air.
Evaporation is a cooling process that absorbs latent heat, therefore the
more evaporation the more cooling.
35.
36. 7. Suctionpotential,or by usingtheisopiesticmethod
The isopiestic method consists of equilibrating both a sample and a
reference material in an evacuated desiccator until equilibrium is reached
at 25°C.
The moisture content of the reference material is then determined and
the aw obtained from the sorption isotherm.
Since the sample was in equilibrium with the reference material, the aw
of both is the same.
37. 8. Bithermalequilibrium(ThermocouplePsychrometer)
Water activity measurement is based on wet bulb temperature
depression.
A thermocouple is placed in the chamber where the sample is
equilibrated. Water is then sprayed over the thermocouple before it is
allowed to evaporate, causing a decrease in temperature.
The drop in temperature is related to the rate of water evaporation from
the surface of the thermocouple, which is a function of the relative
humidity in equilibrium with the sample.
38. 9. Electrichygrometers
Most hygrometers are electrical wires coated with hygroscopic salts or
sulfonated polystyrene gel in which conductance or capacitance changes
as the coating absorbs moisture from the sample.
The major disadvantage of this type of hygrometer is the tendency of
the hygroscopic salt to become contaminated with polar compounds,
resulting in erroneous aw determinations.
39. 10. Hairhygrometers
Hair hygrometers are based on the stretching of a fibre when exposed to
high water activity.
They are less sensitive than other instruments at lower levels of activity
(<0.03 aw) and the principal disadvantage of these types of meters is the
time delay in reaching equilibrium and the tendency to hysteresis.
Today we find many brands of water activity meters in the market. Most
of these meters are based on the relationship between ERH and the food
system, but differ in their internal components and configuration of
software used.
One of the water activity meters most used today is the AcquaLab
Series 3 Model TE, developed by Decagon Devices, which is based on the
chilled-mirror dew point method.
40. This instrument is a temperature controlled water activity meter that
allows placement of the sample in a temperature stable environment
without the use of an external water bath.
The temperature can be selected on the screen and is monitored and
controlled with thermoelectric components.
Most of the older generations of water activity instruments are based
on a temperature-controlled environment.
Therefore, a margin of error greater than 5% can be expected due to
temperature variations.
This equipment is highly recommended for measuring water activity in
fruits and vegetables since it measures a wide range of water activity.
The major advantages of the chilled-mirror dew point method are
accuracy, speed, ease of use and precision.
The AquaLab's range is from 0.030 to 1.000aw, with a resolution of
±0.001aw and accuracy of ±0.003aw.
41. Measurement time is typically less than five minutes.
Capacitance sensors have the advantage of being inexpensive, but are
not usually as accurate or as fast as the chilled-mirror dew point
method.
Capacitive instruments measure over the entire water activity range 0 to
1.00 aw, with a resolution of ±0.005aw and accuracy of ±0.015aw.
Some commercial instruments can complete measurements in five minutes
while other electronic capacitive sensors usually require 30 to 90 minutes
to reach equilibrium relative humidity conditions.
The hair hygrometer uses the characteristic of the hair that its length
expands or shrinks response to the relative humidity. ...
The length of human hair from which liquid are removed increases by 2
to 2.5% when relative humidity changes by 0 to 100%.
42. Principleof Hairhygrometer
Due to humidity, several materials undergo a change in physical,
chemical and electrical properties.
This property is used in a transducer designed and calibrated to
directly read the relative humidity.
Certain hygroscopic materials, such as human hair, animal membranes,
wood, paper, etc., undergo changes in the linear dimensions when they
absorb moisture from the surrounding air.
This change in the linear dimension is used as the measurement of the
humidity present in the air.
43. Workingof hairhygrometer:
When air humidity is to be measured, this air is made to surround
the hair arrangement and the hair arrangement absorbs moisture from
the surrounding air and expands or contracts in the linear direction.
This expansion or contraction of the hair arrangement moves the arm
and the link and, therefore, the pointer to a suitable position on the
calibrated scale and, therefore, indicates the humidity present in the
air / atmosphere.
These Hair hydrometers are called membrane hydrometers when the
sensing element is a membrane.
44. Human hair is used as a humidity sensor.
The hair is arranged on a parallel beam and separated from each other to
expose them to the surrounding air / atmosphere.
Number of hairs are placed in parallel to increase the mechanical strength.
This hair arrangement is placed under a small tension by the use of a
tension spring to ensure proper functioning.
The hair arrangement is connected to an arm and a link arrangement and
the link is attached to a pointer rotated at one end. The pointer sweeps
over a calibrated scale of humidity.
45. Applicationof Hairhygrometer
These hydrometers are used in the temperature range of 0’C to 75’C.
These hydrometers are used in the range of relative humidity (relative
humidity) from 30 to 95%.
Limitations of the hydrometer for the hair
These hydrometers are slow in response
If the hair hydrometer is used constantly, its calibration tends to
change.
50. Advantages
The main advantages of this technology are its rather low cost
and a greater insensitivity to volatile substances such as alcohol
and propylene glycol.
Disadvantages
The main disadvantages of this technology are the loss of
efficiency of the sensor over time and fouling issues.
Advantages& Disadvantagesof WaterActivity