1. Lipids include triglycerides, fatty acids, phospholipids, sterols, and cholesterol. They provide energy, aid nutrient absorption, and structure cell membranes.
2. Triglycerides are composed of a glycerol molecule bonded to three fatty acids and make up most dietary and body lipids. Cholesterol is an important sterol.
3. Essential fatty acids must be obtained through diet and include linoleic and alpha-linolenic acids. Phospholipids are structural components of membranes.
this slides will help to provide the better information about the role, properties, nutritive aspect of Fat and oil.
can be use by under graduate or post graduate students as well.
Controlled atmosphere storage (CAS) involves storing horticultural commodities under controlled levels of oxygen and carbon dioxide at an optimized temperature to preserve food quality. Typical CAS conditions for fruit preservation are 5% oxygen and 1% carbon dioxide. CAS provides advantages like extended shelf life, delayed ripening, and reduced disease and insect damage compared to normal atmosphere storage. However, CAS also has disadvantages like higher costs and the need for specialized equipment and temperature control.
Food science involves the study of nutrients, additives, and changes that occur during food processing and preparation. Nutrients are classified as macronutrients, which are needed in large quantities, or micronutrients, which are needed in small amounts. Food science helps retain nutrients and ensures food is safe, wholesome and palatable through the study of physical and chemical changes during cooking and preservation. The functions of food include building the body, providing energy, regulating processes, and maintaining health. Food is essential for sustaining life.
The above presentation discuss about the stages of sugar cookery and difference between crystalline and non-crystalline candy. The different stages of sugar cookery is been explained step by step with pictorial representation for easy understanding. Temperature and the physical properties of the different stages of sugar cookery is been tabulate and the food products made by these stages of sugar is also mentioned. The difference between crystalline and non-crystalline candy their physical and chemical properties and changes is also explained.
The document discusses ghee, including its definition as clarified butter, types, properties, methods of preparation and manufacturing, defects, adulteration, food value, benefits and uses. It describes the common methods like desi, creamery butter and pre-stratification. Equipment used in manufacturing includes cream separators, ghee boilers, butter churners and filtration tanks. Ghee provides energy, good fats and vitamins while benefits include memory, skin and hair health. It is commonly used in Indian and Middle Eastern cooking and can be packaged in materials like tin, glass or laminates for storage.
Echium plantagineum oil is a novel food ingredient derived from the seeds of Echium plantagineum. It is a rich source of omega-3 and omega-6 fatty acids. Some key applications of Echium oil include use in skin care products to reduce signs of aging and inflammation, as well as promoting cardiovascular health due to its fatty acid composition. Echium oil has potential future applications and its market is projected to grow in the coming years due to investments in research and its various health benefits.
This document discusses the physicochemical properties of milk constituents such as water, milk fat, milk proteins, lactose, and minerals. It describes the size, structure, and composition of milk fat globules. It also summarizes the types and properties of casein and whey proteins, lactose, and minor milk constituents including phospholipids, pigments, enzymes, cholesterol, and vitamins. The document then covers additional physicochemical properties of milk such as acidity, pH, density, specific gravity, freezing point, boiling point, color, and flavor.
Pulse milling and their byproduct utilizationKRATIKA SINGHAM
This document discusses pulse milling and utilization of byproducts. It begins by defining pulses as edible legume seeds harvested dry. India is a major producer, consumer, and importer of pulses. The document then covers pulse nutrition, health benefits, production statistics in India, post-harvest losses, and milling processes including home, cottage, and commercial scale milling. It describes various pre-treatment methods like wet treatments using water and red earth and dry treatments using oil and water application followed by tempering and sun drying to loosen the husk prior to milling. The goal of milling is efficient removal of husk from cotyledons with minimal losses.
this slides will help to provide the better information about the role, properties, nutritive aspect of Fat and oil.
can be use by under graduate or post graduate students as well.
Controlled atmosphere storage (CAS) involves storing horticultural commodities under controlled levels of oxygen and carbon dioxide at an optimized temperature to preserve food quality. Typical CAS conditions for fruit preservation are 5% oxygen and 1% carbon dioxide. CAS provides advantages like extended shelf life, delayed ripening, and reduced disease and insect damage compared to normal atmosphere storage. However, CAS also has disadvantages like higher costs and the need for specialized equipment and temperature control.
Food science involves the study of nutrients, additives, and changes that occur during food processing and preparation. Nutrients are classified as macronutrients, which are needed in large quantities, or micronutrients, which are needed in small amounts. Food science helps retain nutrients and ensures food is safe, wholesome and palatable through the study of physical and chemical changes during cooking and preservation. The functions of food include building the body, providing energy, regulating processes, and maintaining health. Food is essential for sustaining life.
The above presentation discuss about the stages of sugar cookery and difference between crystalline and non-crystalline candy. The different stages of sugar cookery is been explained step by step with pictorial representation for easy understanding. Temperature and the physical properties of the different stages of sugar cookery is been tabulate and the food products made by these stages of sugar is also mentioned. The difference between crystalline and non-crystalline candy their physical and chemical properties and changes is also explained.
The document discusses ghee, including its definition as clarified butter, types, properties, methods of preparation and manufacturing, defects, adulteration, food value, benefits and uses. It describes the common methods like desi, creamery butter and pre-stratification. Equipment used in manufacturing includes cream separators, ghee boilers, butter churners and filtration tanks. Ghee provides energy, good fats and vitamins while benefits include memory, skin and hair health. It is commonly used in Indian and Middle Eastern cooking and can be packaged in materials like tin, glass or laminates for storage.
Echium plantagineum oil is a novel food ingredient derived from the seeds of Echium plantagineum. It is a rich source of omega-3 and omega-6 fatty acids. Some key applications of Echium oil include use in skin care products to reduce signs of aging and inflammation, as well as promoting cardiovascular health due to its fatty acid composition. Echium oil has potential future applications and its market is projected to grow in the coming years due to investments in research and its various health benefits.
This document discusses the physicochemical properties of milk constituents such as water, milk fat, milk proteins, lactose, and minerals. It describes the size, structure, and composition of milk fat globules. It also summarizes the types and properties of casein and whey proteins, lactose, and minor milk constituents including phospholipids, pigments, enzymes, cholesterol, and vitamins. The document then covers additional physicochemical properties of milk such as acidity, pH, density, specific gravity, freezing point, boiling point, color, and flavor.
Pulse milling and their byproduct utilizationKRATIKA SINGHAM
This document discusses pulse milling and utilization of byproducts. It begins by defining pulses as edible legume seeds harvested dry. India is a major producer, consumer, and importer of pulses. The document then covers pulse nutrition, health benefits, production statistics in India, post-harvest losses, and milling processes including home, cottage, and commercial scale milling. It describes various pre-treatment methods like wet treatments using water and red earth and dry treatments using oil and water application followed by tempering and sun drying to loosen the husk prior to milling. The goal of milling is efficient removal of husk from cotyledons with minimal losses.
This document discusses food processing. Food processing transforms raw ingredients into food for human or animal consumption through methods like peeling, mincing, chopping, emulsification, fermentation, liquefaction, baking, and packaging. It defines food processing as using methods and techniques to transform raw crops and slaughtered animal products into attractive, marketable food products with a longer shelf life.
Principles And Methods For Food PreservationMohit Jindal
The document discusses principles and methods for food preservation. It explains that food preservation prevents spoilage by removing microorganisms, inactivating enzymes, and removing insects and rodents. Common preservation methods include dehydration, lowering temperature through refrigeration or freezing, increasing temperature through pasteurization or sterilization, and using preservatives like salt, sugar, or chemicals. Specific preservation techniques are outlined for items like potatoes, peas, and greens through methods like sun drying, blanching, and freezing. The goal of preservation is to retain a food's quality, nutrients, and extend its safe storage lifespan.
Ghee is a clarified butter fat produced from cow or buffalo milk. About 1 million tons of ghee are produced annually in India through various methods. The pre-stratification method involves separating butter into 3 layers, with the middle layer containing the clearest fat used to produce ghee. Ghee has a characteristic flavor due to carbonyls and lactones produced during clarification. It is graded based on chemical and physical parameters like acid value and melting point. Adulterants include hydrogenated vegetable oils substituted for the more expensive dairy fat.
This document provides an overview of a seminar presentation on using radiation as a method of food preservation. It discusses the history of using radiation to preserve foods, different types of radiation used including UV, ionizing radiation, electron beams and microwaves. It also covers topics like irradiated foods, dosimetry, applications and benefits of food irradiation, as well as limitations. The presentation aims to establish food irradiation as a safe and effective food processing technique while acknowledging it has not been widely adopted by consumers.
This document discusses different measurement techniques used in food science, including density, phase change, pH, osmosis, surface tension, and colloidal systems. It provides definitions and examples for each measurement. Density is defined as mass per unit volume and is represented by the Greek letter p. Phase changes refer to changes in state, such as freezing or boiling water. pH is defined as the negative logarithm of hydrogen ion concentration and is measured using a pH meter. Osmosis and reverse osmosis describe the diffusion of solvent molecules across a semi-permeable membrane, with or against a concentration gradient. Surface tension is the force per unit length at a liquid's surface. Colloidal systems have particle sizes between true
This document discusses various oil seed crops, their nutritional values, and production. It outlines several major oil seed crops including soybeans, flaxseed, peanuts, olives, sesame, coconut, and sunflower. For each crop, it provides details on scientific name, where it is grown, common uses, and nutritional values per 100g. It also discusses problems with oil seed crop production in Pakistan, such as low yields and reliance on imports, and proposes solutions like increasing farmer education, investment in technology, and use of hybrid seeds.
This presentation provides information on pulses, including their nutritional composition and processing methods to improve digestibility. Pulses are a good source of protein but also contain anti-nutritional factors. Processing through soaking, germination, cooking, and fermentation can reduce these factors and increase protein availability. Proper processing is important to maximize the nutritional benefits of pulses.
Vegetables are important part of our daily diet, It has essential nutrients that helps in normal functioning of the body. Pigments present in them are responsible for the colour before and prior to cooking. They too have nutritional aspects
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.
Jams, Jellies, Marmalades, and Candied FruitsMAILYNVIODOR1
This document discusses various traditional methods for preserving fruits, vegetables, meat, fish, and other foods in the Philippines. It describes how jams, marmalades, jellies, and candied fruits are made by cooking fruits in sugar to prevent spoilage. Pickling in brine is used to preserve vegetables. Meat is cured through salting, sugar, spices and saltpeter. Fish are dried or fermented, while small seafood like anchovies are fermented in salt to make patis and bagoong. The best preservation starts with high quality, fresh ingredients.
The document provides information about a seminar on drying and dehydration of fruit crops. It discusses various topics related to drying and dehydration including principles, pre-treatment, drying techniques, benefits of dried fruit, and research findings. The key points are that drying and dehydration remove water from fruits to preserve them by inhibiting microbial growth. Various techniques are used for drying including sun drying, tray drying, tunnel drying, and freeze drying. Pre-treatment and proper drying conditions help maintain fruit quality and nutritional value during the drying process.
Canning or bottling is a method of food preservation that involves placing foods in jars or containers and heating them to temperatures that destroy microorganisms. There are two safe canning methods - the boiling water bath method for high acid foods like fruits and pickles, and the pressure canner method for low acid foods like vegetables and meats, which reaches temperatures above boiling to kill deadly botulinum toxins. Canning prevents spoilage by driving out air from the jar and creating a vacuum seal to prevent reentry of microbes when the jar cools.
The document discusses the process of poultry processing from slaughtering to packaging. It begins by defining key terms like abattoir and carcass. It then describes the traditional and modern methods of slaughtering including steps like stunning, sticking, bleeding, scalding, picking and evisceration. After slaughtering, the processing steps discussed are chilling, grading, packaging and storage. The document also provides information on poultry meat properties, grading systems and popular chicken products. It concludes by noting that while India has a large poultry market, modern slaughter techniques have yet to be widely adopted.
This document discusses colloidal systems found in food. It begins by defining mixtures, solutions, suspensions, and colloids. A colloid is a mixture with particle sizes between solutions and suspensions. Common colloidal systems in food include sols, gels, and emulsions. Sols have solid particles dispersed in a liquid, while gels are solidified sols. Emulsions disperse one liquid into another immiscible liquid. Food colloids are important for texture, structure, stability, and maintaining properties of food systems.
The document summarizes the process of making puffed grains. It describes how Dr. Alexander P. Anderson invented the modern puffing process using heat and steam to cause grains like rice, wheat, and corn to explode and increase dramatically in volume. The puffing process works by heating grain kernels that contain water, converting the water to steam which builds pressure until the grain's pericarp bursts, allowing the starch and proteins to expand into a puffed shape. Common puffing methods described are oven puffing, gun puffing, extrusion puffing, and oil puffing for popcorn. The puffing process increases the grain's volume 6-8 times and results in popular breakfast cereals like Rice Krispies and Cheerios
This document summarizes different types of fat replacers including carbohydrate-based, protein-based, and fat-based replacers. It discusses specific examples such as olestra, salatrim, and polyols. It also reviews potential health benefits and safety issues of fat replacers related to calories, lipids, vitamins, and drug absorption. While fat replacers may reduce fat and calorie intake, long-term weight loss requires behavioral changes to energy intake and expenditure.
Preservation involves preventing the growth of microorganisms like bacteria, yeast and fungi to prevent food spoilage. It maintains the color, taste and nutrients of food. Microorganisms, enzymes and insects/rodents cause spoilage. Preservation methods remove or inactivate microbes through processes like drying, curing, refrigeration and freezing or use of chemicals like salt, sugar and vinegar. Other methods are pasteurization, radiation and packaging foods airtight. The document discusses the various preservation techniques used to extend the shelf life of foods.
This document summarizes the structure and composition of legume seeds. It notes that legumes are an important family of dicotyledonous plants that include crops like peas, beans, lentils, peanuts and soybeans. These legume seeds have three main parts - the seed coat, cotyledons, and hypocotyl. The cotyledons make up around 90% of the seed and contain protein bodies and lipid deposits that neatly package the proteins and lipids. The size and structure of these protein bodies and lipid deposits varies between different legumes. The document provides examples of the size and packaging of proteins, lipids and starches in seeds of soybeans, peanuts, peas and broad beans.
This document discusses protein isolates and concentrates. It defines isolates as highly refined protein products containing mostly protein with no fiber. Isolates can be obtained from plant and animal sources through various extraction methods like isoelectric precipitation and ultrafiltration. Protein concentrates contain some carbohydrates and have a lower protein content than isolates. Common protein isolates discussed include whey, fish, peanut, soy, canola, chickpea and cashew nut isolates. The functional properties of isolates like bulk density, solubility, and foaming capacity are also described.
“These are the naturally Organic compounds, insoluble in water, soluble in organic solvents (alcohol, ether, etc.), which are potentially related to fatty acids & utilized by living cells."
Lipids are a heterogeneous group of compounds.
They are esters of fatty acids. Lipids occur widely in plants and animals. Lipids include fats, oils, waxes, and related compounds.
Lipids are a family of organic compounds, composed of fats and oils. These molecules yield high energy and are responsible for different functions within the human body.
Lipids are insoluble in water but soluble in organic solvents and serve important functions in living cells. They include fats, oils, waxes, sterols like cholesterol, and phospholipids. The main functions of lipids are storing energy, acting as structural components of cell membranes, and cell signaling. Common lipids in the diet include fats and oils. High lipid levels can be caused by diet, genetic disorders, or medical conditions like diabetes. Lipids are made of fatty acids and glycerol. Fatty acids can be saturated or unsaturated, affecting their melting point. Humans must obtain certain unsaturated fatty acids through diet as essential fatty acids.
This document discusses food processing. Food processing transforms raw ingredients into food for human or animal consumption through methods like peeling, mincing, chopping, emulsification, fermentation, liquefaction, baking, and packaging. It defines food processing as using methods and techniques to transform raw crops and slaughtered animal products into attractive, marketable food products with a longer shelf life.
Principles And Methods For Food PreservationMohit Jindal
The document discusses principles and methods for food preservation. It explains that food preservation prevents spoilage by removing microorganisms, inactivating enzymes, and removing insects and rodents. Common preservation methods include dehydration, lowering temperature through refrigeration or freezing, increasing temperature through pasteurization or sterilization, and using preservatives like salt, sugar, or chemicals. Specific preservation techniques are outlined for items like potatoes, peas, and greens through methods like sun drying, blanching, and freezing. The goal of preservation is to retain a food's quality, nutrients, and extend its safe storage lifespan.
Ghee is a clarified butter fat produced from cow or buffalo milk. About 1 million tons of ghee are produced annually in India through various methods. The pre-stratification method involves separating butter into 3 layers, with the middle layer containing the clearest fat used to produce ghee. Ghee has a characteristic flavor due to carbonyls and lactones produced during clarification. It is graded based on chemical and physical parameters like acid value and melting point. Adulterants include hydrogenated vegetable oils substituted for the more expensive dairy fat.
This document provides an overview of a seminar presentation on using radiation as a method of food preservation. It discusses the history of using radiation to preserve foods, different types of radiation used including UV, ionizing radiation, electron beams and microwaves. It also covers topics like irradiated foods, dosimetry, applications and benefits of food irradiation, as well as limitations. The presentation aims to establish food irradiation as a safe and effective food processing technique while acknowledging it has not been widely adopted by consumers.
This document discusses different measurement techniques used in food science, including density, phase change, pH, osmosis, surface tension, and colloidal systems. It provides definitions and examples for each measurement. Density is defined as mass per unit volume and is represented by the Greek letter p. Phase changes refer to changes in state, such as freezing or boiling water. pH is defined as the negative logarithm of hydrogen ion concentration and is measured using a pH meter. Osmosis and reverse osmosis describe the diffusion of solvent molecules across a semi-permeable membrane, with or against a concentration gradient. Surface tension is the force per unit length at a liquid's surface. Colloidal systems have particle sizes between true
This document discusses various oil seed crops, their nutritional values, and production. It outlines several major oil seed crops including soybeans, flaxseed, peanuts, olives, sesame, coconut, and sunflower. For each crop, it provides details on scientific name, where it is grown, common uses, and nutritional values per 100g. It also discusses problems with oil seed crop production in Pakistan, such as low yields and reliance on imports, and proposes solutions like increasing farmer education, investment in technology, and use of hybrid seeds.
This presentation provides information on pulses, including their nutritional composition and processing methods to improve digestibility. Pulses are a good source of protein but also contain anti-nutritional factors. Processing through soaking, germination, cooking, and fermentation can reduce these factors and increase protein availability. Proper processing is important to maximize the nutritional benefits of pulses.
Vegetables are important part of our daily diet, It has essential nutrients that helps in normal functioning of the body. Pigments present in them are responsible for the colour before and prior to cooking. They too have nutritional aspects
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.
Jams, Jellies, Marmalades, and Candied FruitsMAILYNVIODOR1
This document discusses various traditional methods for preserving fruits, vegetables, meat, fish, and other foods in the Philippines. It describes how jams, marmalades, jellies, and candied fruits are made by cooking fruits in sugar to prevent spoilage. Pickling in brine is used to preserve vegetables. Meat is cured through salting, sugar, spices and saltpeter. Fish are dried or fermented, while small seafood like anchovies are fermented in salt to make patis and bagoong. The best preservation starts with high quality, fresh ingredients.
The document provides information about a seminar on drying and dehydration of fruit crops. It discusses various topics related to drying and dehydration including principles, pre-treatment, drying techniques, benefits of dried fruit, and research findings. The key points are that drying and dehydration remove water from fruits to preserve them by inhibiting microbial growth. Various techniques are used for drying including sun drying, tray drying, tunnel drying, and freeze drying. Pre-treatment and proper drying conditions help maintain fruit quality and nutritional value during the drying process.
Canning or bottling is a method of food preservation that involves placing foods in jars or containers and heating them to temperatures that destroy microorganisms. There are two safe canning methods - the boiling water bath method for high acid foods like fruits and pickles, and the pressure canner method for low acid foods like vegetables and meats, which reaches temperatures above boiling to kill deadly botulinum toxins. Canning prevents spoilage by driving out air from the jar and creating a vacuum seal to prevent reentry of microbes when the jar cools.
The document discusses the process of poultry processing from slaughtering to packaging. It begins by defining key terms like abattoir and carcass. It then describes the traditional and modern methods of slaughtering including steps like stunning, sticking, bleeding, scalding, picking and evisceration. After slaughtering, the processing steps discussed are chilling, grading, packaging and storage. The document also provides information on poultry meat properties, grading systems and popular chicken products. It concludes by noting that while India has a large poultry market, modern slaughter techniques have yet to be widely adopted.
This document discusses colloidal systems found in food. It begins by defining mixtures, solutions, suspensions, and colloids. A colloid is a mixture with particle sizes between solutions and suspensions. Common colloidal systems in food include sols, gels, and emulsions. Sols have solid particles dispersed in a liquid, while gels are solidified sols. Emulsions disperse one liquid into another immiscible liquid. Food colloids are important for texture, structure, stability, and maintaining properties of food systems.
The document summarizes the process of making puffed grains. It describes how Dr. Alexander P. Anderson invented the modern puffing process using heat and steam to cause grains like rice, wheat, and corn to explode and increase dramatically in volume. The puffing process works by heating grain kernels that contain water, converting the water to steam which builds pressure until the grain's pericarp bursts, allowing the starch and proteins to expand into a puffed shape. Common puffing methods described are oven puffing, gun puffing, extrusion puffing, and oil puffing for popcorn. The puffing process increases the grain's volume 6-8 times and results in popular breakfast cereals like Rice Krispies and Cheerios
This document summarizes different types of fat replacers including carbohydrate-based, protein-based, and fat-based replacers. It discusses specific examples such as olestra, salatrim, and polyols. It also reviews potential health benefits and safety issues of fat replacers related to calories, lipids, vitamins, and drug absorption. While fat replacers may reduce fat and calorie intake, long-term weight loss requires behavioral changes to energy intake and expenditure.
Preservation involves preventing the growth of microorganisms like bacteria, yeast and fungi to prevent food spoilage. It maintains the color, taste and nutrients of food. Microorganisms, enzymes and insects/rodents cause spoilage. Preservation methods remove or inactivate microbes through processes like drying, curing, refrigeration and freezing or use of chemicals like salt, sugar and vinegar. Other methods are pasteurization, radiation and packaging foods airtight. The document discusses the various preservation techniques used to extend the shelf life of foods.
This document summarizes the structure and composition of legume seeds. It notes that legumes are an important family of dicotyledonous plants that include crops like peas, beans, lentils, peanuts and soybeans. These legume seeds have three main parts - the seed coat, cotyledons, and hypocotyl. The cotyledons make up around 90% of the seed and contain protein bodies and lipid deposits that neatly package the proteins and lipids. The size and structure of these protein bodies and lipid deposits varies between different legumes. The document provides examples of the size and packaging of proteins, lipids and starches in seeds of soybeans, peanuts, peas and broad beans.
This document discusses protein isolates and concentrates. It defines isolates as highly refined protein products containing mostly protein with no fiber. Isolates can be obtained from plant and animal sources through various extraction methods like isoelectric precipitation and ultrafiltration. Protein concentrates contain some carbohydrates and have a lower protein content than isolates. Common protein isolates discussed include whey, fish, peanut, soy, canola, chickpea and cashew nut isolates. The functional properties of isolates like bulk density, solubility, and foaming capacity are also described.
“These are the naturally Organic compounds, insoluble in water, soluble in organic solvents (alcohol, ether, etc.), which are potentially related to fatty acids & utilized by living cells."
Lipids are a heterogeneous group of compounds.
They are esters of fatty acids. Lipids occur widely in plants and animals. Lipids include fats, oils, waxes, and related compounds.
Lipids are a family of organic compounds, composed of fats and oils. These molecules yield high energy and are responsible for different functions within the human body.
Lipids are insoluble in water but soluble in organic solvents and serve important functions in living cells. They include fats, oils, waxes, sterols like cholesterol, and phospholipids. The main functions of lipids are storing energy, acting as structural components of cell membranes, and cell signaling. Common lipids in the diet include fats and oils. High lipid levels can be caused by diet, genetic disorders, or medical conditions like diabetes. Lipids are made of fatty acids and glycerol. Fatty acids can be saturated or unsaturated, affecting their melting point. Humans must obtain certain unsaturated fatty acids through diet as essential fatty acids.
This document provides information about lipids and fats. It begins by defining lipids and explaining that they are a major building block of animal cells. It then discusses the different types of lipids, including simple lipids like fats and oils, complex lipids like phospholipids, and derived lipids like cholesterol. The document explains the classification and functions of various lipids such as phospholipids, essential fatty acids, and saturated and unsaturated fatty acids. It also covers the digestion and absorption of lipids, as well as the different types of cholesterol and their importance.
This document discusses lipids (fats) including their composition, classification, functions, sources, and deficiencies. Lipids are comprised of carbon, hydrogen, and oxygen and provide 9 calories per gram. They are classified as simple lipids, compound lipids, waxes, and derived lipids. The main lipids in diet are triglycerides, phospholipids, and sterols. Triglycerides make up 95% of dietary and body lipids and are broken down into glycerol and fatty acids. Phospholipids are important structures in membranes. Sterols are precursors to bile acids and sex hormones. Fats have many important functions like being an energy source and aiding vitamin absorption. Deficiencies can cause skin disorders like
This document discusses fats and lipids, including their classification, sources, functions, and health effects. It covers the different types of fats such as simple/neutral fats, compound lipids, and derived lipids. Key points include that fats provide calories and cushion for organs, facilitate absorption of fat-soluble vitamins, and sources include visible fats like butter and invisible fats in foods like milk. Excessive saturated fat intake can increase risk of heart disease and cancer, while omega-3 fatty acids may decrease risk. The document provides tips for lowering fat intake such as eating fatty foods in moderation and adding more healthy options.
Food groups provide different nutrients. Water contains minerals. Fruits and vegetables contain vitamins, minerals, and fiber. Meat, fish, eggs and tofu mainly provide protein along with minerals and vitamins. Dairy provides calcium, protein, lipids, and vitamins. Cereals, potatoes and pulses contain carbohydrates, proteins, vitamins, minerals, and fiber. The fats group is high in lipids and contains some vitamins. Lipids contain carbon, hydrogen and oxygen and provide energy, aid nutrient absorption, and have structural and signaling functions in the body. Lipids are classified based on their structure and components.
Lipids are a group of organic compounds that include fats, oils, steroids, and phospholipids. They are insoluble in water and serve important functions in the body such as energy storage, insulation, and cell membrane structure. There are three main classes of lipids: triglycerides which include fats and oils, phospholipids including lecithin, and sterols such as cholesterol. Fats can be saturated, existing as solids at room temperature, or unsaturated and liquid. Hyperlipoproteinemia is a disorder where the body cannot break down lipids properly and is often genetic, leading to high lipid levels in the blood and symptoms like pancreatitis or lipid deposits. It is diagnosed via blood tests
This document provides information on fats and their classification and properties. It discusses that fats can be classified based on their chemical composition into simple lipids, compound lipids, and derived lipids. Fats are also classified based on their fatty acid composition into saturated and unsaturated fatty acids like mono- and polyunsaturated fatty acids. The document outlines the main functions of fats in the body and discusses the physical and chemical properties of fats like crystallization, viscosity, rancidity, and hydrogenation. It provides details on the mechanisms and processes involved in the chemical reactions of fats.
Lipids are organic compounds that are insoluble in water but soluble in organic solvents. They include fats, oils, waxes, sterols and phospholipids. Fats and oils are triglycerides composed of glycerol and fatty acids. Fatty acids are classified as saturated, monounsaturated, or polyunsaturated. Phospholipids are a major component of cell membranes and lipoproteins transport lipids in the blood. Lipids serve important functions as energy stores, insulation, and as precursors to other compounds like hormones and vitamins.
Lipids are a heterogeneous group of organic compounds that are insoluble in water but soluble in organic solvents. They include fats, waxes, sterols, fat-soluble vitamins, monoglycerides, and phospholipids. Lipids are an essential part of cell membranes and a stored form of energy. Cholesterol is an important lipid that helps form cell membranes and is a precursor for vitamin D and steroid hormones. Essential fatty acids must be obtained from dietary sources and are important for biological functions.
This document provides information about lipids. It defines lipids as long chains of carbon and hydrogen molecules that are insoluble in water. Lipids serve as an important energy source and provide structure to cell membranes. They are classified based on their components, with simple lipids like fats and oils consisting of fatty acids and glycerol, and complex lipids also containing additional groups like phosphates or carbohydrates. Lipids play key roles in the body such as energy storage, insulation, and as precursors to hormones and vitamins. The document discusses the structure and examples of different lipid types as well as their biological functions.
Lipids definition and classification with examples Hitarth Solanki
This seminar presentation discusses lipids, their definition, classification, and examples. It begins with introducing the presenter and topic. It then defines lipids as insoluble organic compounds consisting of hydrogen, carbon, and oxygen that perform important biological functions. Lipids are classified as simple/homolipids including fats/oils, waxes, and derived lipids including fatty acids, alcohols, and steroids. Examples of fixed oils like cottonseed oil, linseed oil, and olive oil are described along with their botanical origins, constituents, uses, and toxicity. The differences between fats/oils and volatile/fixed oils are also summarized.
This document discusses fats, their composition, classification, sources, functions, digestion and metabolism. It notes that fats are composed of glycerol and fatty acids. They can be simple (monoglycerides, diglycerides) or compound (phospholipids, glycolipids, lipoproteins). Fats provide energy, aid vitamin absorption, are essential for cell membranes and hormones, and improve diet palatability. The document outlines the digestion, absorption and transport of fats through micelles and chylomicrons, as well as fat storage and metabolism in the liver and adipose tissue.
Storage lipids like triglycerides are composed of fatty acids esterified to a glycerol backbone. They serve as energy stores. Animal fats and oils come from rendered animal tissues and secretions. Popular animal fats include lard, tallow, butter, and dairy oils. They are used in foods, soaps, lubricants and other products. Properties depend on fatty acid composition, with saturated fats usually solid at room temperature.
Lipids are classified as either structural or storage lipids in plants and animals. Structural lipids make up membranes and surface layers, while storage lipids are predominantly triacylglycerols found in seeds and fruits. Plant lipids contain a variety of fatty acids, but alpha-linolenic and linoleic acids are most common. Animal lipids mainly function as stored energy, consisting primarily of saturated fatty acids in adipose tissue. Fats and oils are composed of fatty acid esters of glycerol and differ based on fatty acid composition, with oils being liquid and fats solid at room temperature. Essential fatty acids like linoleic and alpha-linolenic acids are required in the diet.
Fatty acids are the building blocks of the fat in our bodies and in the food we eat. During digestion, the body breaks down fats into fatty acids, which can then be absorbed into the blood. Fatty acid molecules are usually joined together in groups of three, forming a molecule called a triglyceride.
Lipids are a diverse group of organic compounds that include fats, waxes, sterols and phospholipids. They are insoluble in water but soluble in organic solvents. The document discusses the structure and classification of lipids. Key points include:
- Lipids include simple lipids like triglycerides and complex lipids containing additional groups like phospholipids and glycolipids.
- Fatty acids are classified by saturation and chain length. Essential fatty acids must be obtained through diet.
- Phospholipids are major structural components of cell membranes. Glycerophospholipids contain glycerol while sphingophospholipids contain sphingosine.
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The document provides information on entrepreneurship development as a course at Acharya N.G. Ranga Agricultural University.
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- Bagging the female ear shoot and male tassel to collect pollen for cross-pollination.
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1. LIPIDS(FATS)
Fats-Composition and chemistry,classification,
functions,requirements
Nutritional disorders-fats deficiency
Energy metabolism-digestion,absorption and utilization
INTRODUCTION
lipids are a group of naturally occuring substances charaterised by their
insolubality in water and solubility in some organic solvent.
They occur widely in the plant and animal kingdom in the form of oils and
fats respectively.The basic structure of lipids is comprised of
carbon,hydrogen,oxygen.
The lipid fat content of food is the major determinant of the energy
density of dites.
2. Classification
Lipids are classified as:
1.Simple lipids
These are esters of fattyacids and glycerol.Oils are liquid at 200C
while fats are solid at 200C
2.Component lipids
These lipids contain some other organic compounds,in addition to
fatty acids and glycerol they are further characterised as
i)phospholipids(Phosphasides)
3. These contain phospheric acid and a nitrogenous base in addition to
glycerol and fattyacids.lecithin,cephali,plasmalogns come under this
catagory.
ii)Sphingolipids
These contain the base sphingosine or dihydro sphingosine in
addition to glycerol and fattyacids.
iii)Glycolipids
Complex lipids containing carbohydrates in
combination with fatty acids and
sphinogosine.
iv)Sulpho lipids
These contain sulphuric acid in combination with hexose in a
cerebroside.
4. 3.Waxes
These are ester of fatty acids long-chain aliphatic alcohols.
4.Derivedlipids
These includes fatty acids,alohol,sterols
Lipids present in Diets
The lipids present in foods and also in the animals and
human body include:
Triglycerids,
Phospholipids and other compound lipids,and
cholestrol (present only in animals food)
5. Hydrogenation
This is a process involving chemically
induced hydrogen saturation of the carbon
bonds,by which the structure of unsaturated
oils is changed.
This alters the way the body metabolizes
these facts and often changes the physical
form.
Margine and vanaspathi are hydrogenated
facts
6. Functions of Facts
• Fat has several important functions.
• It is a concentrated source of energy yielding more than twice the
energy supplied by carbohydrate per unit weight.
• Fats essential for the absorption of vitamins A,D,Eand K and
carotenoids.
Vegetable fats are good sources of vitamin E and red palm oil is a
good source of carotene while some animal facts such as butter and
fish liver oils are good sources of vitamin
7. • A.Certain vegetable fats are rich sources of the essential fatty acid-
lilolein-acid.
• Fats reduce the bulk of the diet as they provide twice as much
calories as carbohydrates per unit weight.
• Further starchy foods absord lot of water during cooking and
increase the bulk of diet
• Fats improve palatability and give a satiety value ie;a feeling of
fullness in the stomach
• Fats are deposited in adipose tissue acts as an insulting material
against cold and physical injury.
8. Properties of fats
Solubility Fats are soluble in organic solvents such as ethyer ether,
petroleum ether acetone acid Benzine .The quantity of fat present in
food materials is usually determined in by extraction with ethyl ether or
petroleum ether.
Saponification value : THe value is defined as the number of milligrams
of potassium hydroxide required to Saponify 1GM of fat or oil.
Iodine Value :It is the measure of the extent of unaturated fattyb acids
present in fats and oils.It is defined as number of branch of iodine
absorbed in 100Grams of fat.
Reicheit-Mreissl Value :The is defined as the number of milliliters of
0.1N alkali required to neutralize the steam volatile water soluble fatty
acids present in 5Gram sample of fat.that is determine the amount of
butyric acid and caproic acid ewhich are readily soluble in water and a
part of caprylic acid whicc is slightly soluble in water.
9. Thiocyanogen Value :The Thiocyanogen number is the amount of
Thiocyanogen absorbed by 100 g of fat or oil.
Rancidity in fats :
The development of all flavours in fats is known as rancidity.There are
three main types of rancidity,
1.Hydrolytic Rancidity
Hydrolysis of fats by lipase need notb always produce off-flaours.In
the case of butterfat and coconut oil butyric and other low molicular
weight Fatty acids are set free on hydrolysis by lipase.The orders of
these acids contribute largely to the smell of rancidbutter.The
saturated fatty acids such as palmitic and stearic acidsn have little
odour.
10. 2.Oxidative Rancidity
This is the common type of rancidity observed in all fats and oils.The
oxidation takes place at the unsaturated linkage.Certain metals,such
as Copper,Hasten the on set of oxidative rancidity,the addition
ofoxygen to the unsaturated linkage results in the formation of a
peroxide which, on decomposition,yelds aldehydes and ketones
having pronounced off odour.
11. 3.Ketonic rancidity
This type is most frequently as a result of action fungi such as
aspergilles niger and blue green mould,penicillium glaucum on
coconut or oil seeds.The tallow odour developed may be due to
aldehydes and ketones formed by the action of the engymes present
in the fungi on oil.
12. Effects of the essential fatty acid deficiency in
human beings
Phrynoderma:Thus is one pf the common diorders of malnutrition
observed in adults and children.
The condition is characterised by the presence of horny popular
eruptions on the posterior and lateral aspects of the limbs,on the
back and buttoks.
Phrynoderma is cured rapidly by the administration of linseed or
safflower seed oil which are rich in essential fatty acids along with
B-complex vitamines but not by vitamine-A.
13. Deficiency in infants
Hansen and co-workers have reported that infants fed on a
EFA deficient diet developed perennial irritation and changes
in the skin within a few weeks.
The skin changes appears as dryness thickening and
desquamation with oozing in the intertriginous folds.
Supplimemtation of the diet with linaleic acid restored the skin
th normal condition with in 2 weeks.
14. Sources
Rich sources of EFA
safflower,sunflower,nigerseed,cottonseed,linseed,corn,walnut,sesame
and soybean oils are rich in sources of EFA.These oils must form
atleast 50% of the fat in the diet.
Good source:Egg yolk fat,poultryfat and pig body fat are fair sources
of EFA
Poor sources:coconut oil,palmkerneloil,vanaspathy and animal fats
butter and ghee,beef and mutton fat are poor sources of EFA
15. Fat requirements
The approximate fat reqiurements of individuals for different age groups are
given in table.Atleast 50% of the fat oils rich in EFA.
Table:Fat Requirements
Group %
Adults pregnant and lactating mothers 10 to 20 % of total calories from fat
children and adolescents(0 to 18 years) 15 to 20 % of total calories from fat
Infants (Birth to 1 year) 25 to 30 % of total calories from fat
16. 1.Triglycerides and fatty acids :
• Triglycerides comprise about 95% of the food lipids and body lipids.
• They are the storage form of fat.
• When we eat a high calorie diet,the calories in excess of our energy
needs Triglycerides and srored in the body.
• All Triglycerides have a similar structure.It is composed of three fatty
acids attached to a glycerol molecule.
• Glycerol is a short-chain carbohyrate molecule that is soluble in water.
17. • When Triglycerides are metabolized the glycerol is converted to
glucose.
• Fatty acids may differ in their length and their degree of saturation.
• They are commonly composed of a series of 16-18 carbon
molecules attached to hydrogen molecule.
• The number of hydrogen molecules determines the saturation of the
fat.
• When each carbon has its maximum number of hydrogens attached
the fat is set to be saturated.ie., filled to capacity with hydrogen.
18. Saturated fats
Unsaturated fats
Essential fattyacids
Saturated fatty acids: A fatty acid with no carbon-carbon double
bonds.
Monounsaturated fatty acid:A fatty acid containing one double bond.
Polyunsaturated fatty acid:A fatty acid containing two or more double
bond.
Essential fattyacids: THese are fatty acids must be present in the diet
to maintan health,and include lineleic acid and alpha-lineleic acid.
19. Phospholipids :
• Phospholipids are important in the structure of all membranes.
• Their structure is similar to that of triglycerides,but they contain only
two poly unsaturated fatty acids.
• The third molecule attached to the glycerol is a phosphatidylcholine
molecule.
• The most common phospholipid is lacithin.Certain phospholipids also
contain inositol and designated as phosphatldyiinositol.
• Phosphatidylethanolamine is another phosopholipid thatb has
several functions, such as being a precursor to choline and
acetylcholine.
• Lecithin is found in highest concentration in soybeans and
eggyolk.Recently,egg lecithin has been used in the treatment of
accuired immunp deficiency syndrome(AIDS).
20. 3.Sterols/cholesterol
• cholestrol,is the precursor of the bile acids and the sex harmones.it is
manufactured in all tissues of the body except the brain, Cholestrol is
present in all cells and its concentration is particularly high in the liver,
brain and nervous tissue, and the blood.
• Cholestrol, like lecithin is also present in foods,eggyolk,meats,and
other animal fats, milkproducts .It is not present in vegetable foods.
21. • A transport mechhanism of cholestrol called the low density
lipoprotein is the likely cause of risk for the cardiovascullar
disease called atherosclerosis.
• In this condition ,Cholestrol in the form, of LDL cholestrol
accumulates in the living of the arteries these two is the bolld
test currently favoured to elevate risk of cardiovascular disease.
22.
23. Factors affecting requirements
Food intake in is influenced by several factors,two of the most
important being socio-economic status and cultural
preferences.Psychological conditions and risk of certain chronic
diseases such as heart dusease and diabetes also affect fat
requirements.
Digestion and absorption of fat
Several theories have been proposed for the mechanism of absorption
of fats after digestion.The important theories are:
Lipolytic hypothesis of varzar,
Partilition theory of frazer,and micelie theory of borgstrom.
24. Lipolytic hypothesis of varzar
According to this theory,the hydrolysis of fat to fatty acids is complete
and the fatty acid and glycerol are absorbed.The fatty acids combined
with bilesalts to form loosewater miscible complexes which are
absorbed into the intestinal mocosa
The triglycerides are passed on into the lactals of the intestinal
bile.They then enter the lymphasics and reach the systemic the
circulation via thoracduct.
25. Present views on the digestion and
absorption of fat
• Present views on the digestion and absorption of fat are briefly
described below.
• The digestion of the triglyceride proceeds the removal of fatty acid at
the 1 position yeilding fatty acid and a diglyceride, The fatty acid in
the 3 position is then removed by action of lipase leaving 2-
monoglyceride.
• The removal of fatty acid from the 2-monoglyceride is the slow
process.2-monoglyceride will be converted at a slow rate in to 3-
monoglyceride by an enzyme called isomerace.
26. • The monoglyceride and free fatty acids are converted into micelle in
the presence of bile salts and are absorbed into the intestinal wall.
• The free glycerol also is absorbed.3-monoglyceride is hydrolized in the
intestinal wall by the intestinal lipase to fatty acid and glycerol
The in testinal wall has enzyme systemd for fat synthesis.
• The resynthesized fatty acids converted into chylomicrons.
• The chylomicrons enter the lymphatics through lacteals and are
delivered in to the circulation via thoracic duct.
• The fatty acid composition of chylomicrons of the lymph is different
from that of the fat and in the diest as resynthesised in the intestines
using fatty acids derived from food fatand fatty acids present in bile