This document discusses several non-lactic acid bacteria used as starter cultures in food fermentation and their properties, including Bifidobacterium, Propionibacterium, Brevibacterium, and Acetobacter. Bifidobacterium produces acetic and lactic acid and can grow from 25-45°C, with an optimal pH of 6.5-7.0. Propionibacterium is essential for flavor development in Swiss cheeses and grows internally from 25-32°C with an optimal pH of 6.5-7.0. Brevibacterium linens produces enzymes and compounds responsible for flavor and color in surface-ripened cheeses, growing aerobically from 20-
This document discusses molds used as starter cultures in foods and their properties. It provides information on the structure and growth conditions of molds. Major molds used in food production include Penicillium camemberti and P. roqueforti for cheesemaking, and P. nalgiovense for fermented meat sausages. Aspergillus oryzae and A. niger are also used for producing enzymes in foods. Molds are useful in the food industry due to their lytic enzymes and ability to produce flavors and textures in fermented products like cheese and cured meats.
Contamination, Spoilage and preservation of Fruits and VegetablesSuganthiA4
Fruits and vegetables are susceptible to contamination and spoilage from microorganisms during harvesting, processing, and storage. The document discusses sources of contamination like mechanical damage and contact with spoiled produce. It also covers types of spoilage caused by bacteria, molds, and enzymes. Various preservation methods are described like heat treatment, refrigeration, freezing, drying, and use of preservatives to control microbes and extend the shelf life of fruits and vegetables.
The document discusses the various sources and types of food contamination. It identifies four main categories of food contamination: biological, chemical, physical, and cross-contamination. Biological contamination occurs when harmful bacteria or microorganisms spread to food. Chemical contamination involves presence of pesticides, cleaning agents, or unsafe materials. Physical contamination contains foreign objects like hair, glass, or pests. Cross-contamination happens when pathogens are transferred between objects used in food preparation. Proper sanitation, storage, and use of specialized cleaners are recommended to prevent contamination.
This document discusses the microbiology of various foods. It begins by introducing food microbiology and the importance of microorganisms in foods, both desirable and undesirable roles. It then discusses the microbiology of specific foods, including milk and milk products like cheese, butter, and ice cream. It describes the microorganisms commonly found in milk, how they grow, and their effects. It provides details on the microbiology of butter, sources of contamination, types of spoilage, and control methods. It also briefly mentions the microbiology of cheese and cottage cheese.
This document discusses the use of chemicals to preserve foods. It explains that chemical preservatives interfere with microbial cell functions to prevent spoilage. Common chemical preservatives are categorized into two classes. Class I includes salt, sugar, spices, vinegar and alcohol, which preserve foods through osmosis or acidity. Class II includes benzoic acid, sulfur dioxide, nitrates and nitrites, which are considered generally safe within regulatory limits. Specific preservatives discussed are sulfur dioxide, benzoic acid, and sorbic acid, which inhibit microbial growth through various mechanisms.
Intrinsic and extrinsic factors of food spoilageAnni Khan
This document discusses intrinsic and extrinsic factors that influence food spoilage. Intrinsic factors include moisture content, antimicrobial components, biological structures, pH, oxidation-reduction potential, and nutrient content. Extrinsic factors are environmental factors like storage temperature, relative humidity, and gases. Moisture content, pH, and nutrients influence which microbes can grow. Biological structures, antimicrobial components, and oxidation-reduction potential provide resistance. Storage temperature, relative humidity, and gases like carbon dioxide also impact microbial growth during processing and storage.
Sauerkraut is a fermented cabbage product with a sour taste made through the lactic acid fermentation of shredded cabbage by lactic acid bacteria such as Leuconostoc mesenteroides and Lactobacillus plantarum. The fermentation process typically takes 4-8 weeks to produce sauerkraut with an acidity level of around 1.7% and beneficial probiotic bacteria. Sauerkraut is high in fiber, vitamins, and minerals and consumption has various health benefits such as supporting digestive health and reducing inflammation.
This document discusses microorganisms commonly found in various sugar products and how they can cause spoilage. It covers microbes found in maple syrup, honey, candies, chocolate and various sugars. Key points are:
- Maple syrup is initially sterile but becomes contaminated via tapholes with psychrotrophic bacteria like Pseudomonas.
- Honey commonly contains acidophilic and glycolytic yeasts from nectar and bee intestines. Some bacteria also come from bees.
- Candies can contain up to 2 million bacteria mainly from ingredients, air and handling. Spoilage is reduced by proper processing and storage conditions.
This document discusses molds used as starter cultures in foods and their properties. It provides information on the structure and growth conditions of molds. Major molds used in food production include Penicillium camemberti and P. roqueforti for cheesemaking, and P. nalgiovense for fermented meat sausages. Aspergillus oryzae and A. niger are also used for producing enzymes in foods. Molds are useful in the food industry due to their lytic enzymes and ability to produce flavors and textures in fermented products like cheese and cured meats.
Contamination, Spoilage and preservation of Fruits and VegetablesSuganthiA4
Fruits and vegetables are susceptible to contamination and spoilage from microorganisms during harvesting, processing, and storage. The document discusses sources of contamination like mechanical damage and contact with spoiled produce. It also covers types of spoilage caused by bacteria, molds, and enzymes. Various preservation methods are described like heat treatment, refrigeration, freezing, drying, and use of preservatives to control microbes and extend the shelf life of fruits and vegetables.
The document discusses the various sources and types of food contamination. It identifies four main categories of food contamination: biological, chemical, physical, and cross-contamination. Biological contamination occurs when harmful bacteria or microorganisms spread to food. Chemical contamination involves presence of pesticides, cleaning agents, or unsafe materials. Physical contamination contains foreign objects like hair, glass, or pests. Cross-contamination happens when pathogens are transferred between objects used in food preparation. Proper sanitation, storage, and use of specialized cleaners are recommended to prevent contamination.
This document discusses the microbiology of various foods. It begins by introducing food microbiology and the importance of microorganisms in foods, both desirable and undesirable roles. It then discusses the microbiology of specific foods, including milk and milk products like cheese, butter, and ice cream. It describes the microorganisms commonly found in milk, how they grow, and their effects. It provides details on the microbiology of butter, sources of contamination, types of spoilage, and control methods. It also briefly mentions the microbiology of cheese and cottage cheese.
This document discusses the use of chemicals to preserve foods. It explains that chemical preservatives interfere with microbial cell functions to prevent spoilage. Common chemical preservatives are categorized into two classes. Class I includes salt, sugar, spices, vinegar and alcohol, which preserve foods through osmosis or acidity. Class II includes benzoic acid, sulfur dioxide, nitrates and nitrites, which are considered generally safe within regulatory limits. Specific preservatives discussed are sulfur dioxide, benzoic acid, and sorbic acid, which inhibit microbial growth through various mechanisms.
Intrinsic and extrinsic factors of food spoilageAnni Khan
This document discusses intrinsic and extrinsic factors that influence food spoilage. Intrinsic factors include moisture content, antimicrobial components, biological structures, pH, oxidation-reduction potential, and nutrient content. Extrinsic factors are environmental factors like storage temperature, relative humidity, and gases. Moisture content, pH, and nutrients influence which microbes can grow. Biological structures, antimicrobial components, and oxidation-reduction potential provide resistance. Storage temperature, relative humidity, and gases like carbon dioxide also impact microbial growth during processing and storage.
Sauerkraut is a fermented cabbage product with a sour taste made through the lactic acid fermentation of shredded cabbage by lactic acid bacteria such as Leuconostoc mesenteroides and Lactobacillus plantarum. The fermentation process typically takes 4-8 weeks to produce sauerkraut with an acidity level of around 1.7% and beneficial probiotic bacteria. Sauerkraut is high in fiber, vitamins, and minerals and consumption has various health benefits such as supporting digestive health and reducing inflammation.
This document discusses microorganisms commonly found in various sugar products and how they can cause spoilage. It covers microbes found in maple syrup, honey, candies, chocolate and various sugars. Key points are:
- Maple syrup is initially sterile but becomes contaminated via tapholes with psychrotrophic bacteria like Pseudomonas.
- Honey commonly contains acidophilic and glycolytic yeasts from nectar and bee intestines. Some bacteria also come from bees.
- Candies can contain up to 2 million bacteria mainly from ingredients, air and handling. Spoilage is reduced by proper processing and storage conditions.
Criteria for ideal indicators for pathogenic microorganisms in foodNada Sami
The document discusses criteria for ideal indicators of pathogenic microorganisms in food. It outlines that indicators should be of enteric origin and present in higher numbers than pathogens. It then examines various bacterial groups as potential indicators, including coliforms, fecal coliforms, E. coli, and enterococci. While no single indicator meets all criteria, these groups satisfy many as they are nonpathogenic and share habitats with foodborne pathogens. The document evaluates their ability to indicate fecal contamination and potential presence of pathogens in different foods.
This document discusses the various sources of foodborne microorganisms, including the atmosphere, soil, water, plants, and animals. It describes the typical microbial flora found in each environment and how microbes from these sources can contaminate foods and potentially cause spoilage or foodborne illness. The conclusion emphasizes that understanding the natural and transient microflora of foods is important for ensuring food safety during storage and preventing microbial growth.
Cereals and cereal products are susceptible to contamination and spoilage by microorganisms if not properly stored. Moisture content above 13% allows mold and bacterial growth. Common spoilage microorganisms include various bacteria and mold species. Proper preservation methods include low storage temperatures below 7°C, use of preservatives like propionates, and irradiation to reduce microbes. Mold growth is a major cause of bread spoilage and can be prevented through proper cooling, low humidity storage, and surface treatments. Ropiness of bread is caused by Bacillus species surviving baking and growing if conditions are favorable.
This document discusses food hazards and non-bacterial agents of foodborne illness. It begins by defining foodborne disease as any infectious or toxic disease caused by food or water according to the WHO. It then discusses various chemical, bacterial, parasitic, and fungal hazards including toxins produced by algae, fungi, and cyanobacteria. Specific parasites mentioned are Giardia, Entamoeba histolytica, and Cryptosporidium. Prion diseases like scrapie are also summarized. Control methods focus on food inspection and safety practices.
This document discusses contamination and spoilage of canned foods. It describes how canned foods can spoil through three main mechanisms: survival of thermophilic bacterial spores due to inadequate heating; allowing germination of spores due to improper cooling or storage; and recontamination through leaks. It categorizes foods based on pH and outlines various types of biological spoilage caused by thermophilic and mesophilic bacteria, as well as by yeasts and molds. Common spoilage symptoms like gas formation, swelling, souring and black discoloration are also described.
The document discusses several types of fermented vegetables including sauerkraut, kimchi, olives, and pickles. It describes the key ingredients and processes used to ferment each vegetable. Sauerkraut is made from fermented cabbage using a process of shredding, salting, and fermenting the cabbage for several weeks. Kimchi also uses fermented cabbage but includes additional spices and a shorter fermentation time. Olives undergo a lye treatment before being fermented in brine for 6-8 months. Pickles are made by fermenting cucumbers in a brine solution for several weeks. The dominant microorganisms in each fermentation process are various species of lactic
Contamination, Preservation and Spoilage of milkAnil Shrestha
This document discusses sources of contamination and spoilage in milk and milk products. It outlines various sources of contamination on the farm, during transit and processing, including farm equipment, milking utensils, employee hands, and processing equipment. It then discusses methods of preservation like heat, cold temperatures, and preservatives. Finally, it describes different types of spoilage bacteria that can cause souring, gas production, ropiness, proteolysis, lipolysis, and flavor changes in milk, resulting in off-flavors like bitter, burnt, or unusual colors.
1. Cereals and cereal products can be contaminated with bacteria and molds from various sources like the exterior of harvested grains, the environment, and processing equipment.
2. Microbial spoilage of cereals is influenced by moisture level, temperature, and physical damage. Common spoilage microorganisms include molds, yeasts, and bacteria that can produce mycotoxins or cause odors and sourness.
3. Preservation methods to prevent cereal spoilage involve proper storage temperatures, cleaning practices, chemical preservatives, irradiation, and controlling moisture levels. Specific spoilage issues include moldiness, ropiness, and chalky or red discoloration of bread.
The document discusses foodborne infections and intoxications. Foodborne infections occur when harmful microorganisms in contaminated food grow in the intestines and cause illness, while intoxications result from toxins produced by microorganisms or present in plants/seafood. Common bacteria that can cause infections include Salmonella, Listeria, Campylobacter, and viruses like Hepatitis A and parasites such as Giardia. Symptoms include diarrhea and vomiting. Prevention methods include proper food handling and cooking practices.
The document provides an introduction to food microbiology. It discusses how microorganisms can cause food deterioration by utilizing nutrients and producing enzymatic changes. It also discusses the importance of microorganisms in food processing and preservation as well as foodborne illness and spoilage. The document then describes various microorganisms important in food, including molds, yeasts, bacteria, and viruses. It provides examples of both beneficial and spoilage microorganisms and discusses how spoilage occurs.
Foodborne diseases pose a significant threat to public health worldwide. They can be caused by bacteria, viruses, parasites or toxins entering the body through contaminated food. Major pathogens like Salmonella, E. coli and Campylobacter cause foodborne infections and intoxications with symptoms like diarrhea and vomiting. In developing countries, poor hygienic practices and lack of surveillance exacerbate the foodborne disease burden. Proper food safety practices and surveillance systems are needed to reduce illnesses and deaths from these preventable diseases.
Fermentation / fermented food / type of fermented food / microbial action Sumit Bansal
Fermentation in food processing is the process of converting carbohydrates to alcohol or organic acids using microorganisms—yeasts or bacteria—under anaerobic conditions. Fermentation usually implies that the action of microorganisms is desired.
Dr. Babasaheb Nagurao Kumbhar discusses mycotoxins, which are toxic substances produced by fungi that grow on crops. Some key points:
- Mycotoxins are secondary metabolites of fungi that are toxic to other organisms. Unlike bacterial toxins, they are not usually detectable by immune systems.
- Over 300 mycotoxins are known. Major ones of concern include aflatoxins, deoxynivalenol, zearalenone, fumonisin, T-2 toxin, and ochratoxin A.
- Factors like temperature, moisture levels, and storage conditions can favor mycotoxin production. Common toxigenic fungi
The document discusses food microbiology and methods for detecting microbes in food. It describes how microorganisms are introduced to foods and both their beneficial roles in fermentation and spoilage when conditions allow undesirable growth. Detection methods discussed include plate counts, membrane filtration, and microscopic analysis. Intrinsic food factors like pH, water activity, and natural antimicrobials and extrinsic storage conditions like temperature and atmosphere that influence microbial growth are also summarized.
Foodborne infections are caused by ingesting pathogenic microbes that penetrate the intestinal mucosa. The majority of foodborne illness is caused by microorganisms like bacteria, moulds and viruses. Foodborne infections can lead to complications like dehydration and HUS. Foodborne intoxication occurs when toxins produced by bacteria in food like C. botulinum, S. aureus, C. perfringens and B. cereus cause illness. Prevention methods include proper food handling and cooking practices.
This document discusses fermented vegetables. It begins by introducing fermentation as a process where organisms convert carbohydrates into alcohol and/or acid. It then discusses how this process is used to preserve and enhance the flavors of vegetables. Several examples of fermented vegetables are provided, such as sauerkraut, kimchi, and pickles. The document outlines the history of fermented foods and the lactic acid bacteria involved in the fermentation process. Key aspects of producing popular fermented vegetables like sauerkraut are described. Challenges in scaling up production as well as the advantages and limitations of fermented foods are summarized.
Microbial spoilage of food occurs through the growth and activity of microorganisms. Foods provide nutrients that support the growth of microbes that may naturally contaminate foods from various environmental sources. As microbes grow and metabolize nutrients in the food, they can cause undesirable changes in texture, odor, color, flavor and gas production that render the food unacceptable for consumption. The water activity and storage conditions of foods determine whether conditions are suitable for sufficient microbial growth over time to result in spoilage.
Criteria for ideal indicators for pathogenic microorganisms in foodNada Sami
The document discusses criteria for ideal indicators of pathogenic microorganisms in food. It outlines that indicators should be of enteric origin and present in higher numbers than pathogens. It then examines various bacterial groups as potential indicators, including coliforms, fecal coliforms, E. coli, and enterococci. While no single indicator meets all criteria, these groups satisfy many as they are nonpathogenic and share habitats with foodborne pathogens. The document evaluates their ability to indicate fecal contamination and potential presence of pathogens in different foods.
This document discusses the various sources of foodborne microorganisms, including the atmosphere, soil, water, plants, and animals. It describes the typical microbial flora found in each environment and how microbes from these sources can contaminate foods and potentially cause spoilage or foodborne illness. The conclusion emphasizes that understanding the natural and transient microflora of foods is important for ensuring food safety during storage and preventing microbial growth.
Cereals and cereal products are susceptible to contamination and spoilage by microorganisms if not properly stored. Moisture content above 13% allows mold and bacterial growth. Common spoilage microorganisms include various bacteria and mold species. Proper preservation methods include low storage temperatures below 7°C, use of preservatives like propionates, and irradiation to reduce microbes. Mold growth is a major cause of bread spoilage and can be prevented through proper cooling, low humidity storage, and surface treatments. Ropiness of bread is caused by Bacillus species surviving baking and growing if conditions are favorable.
This document discusses food hazards and non-bacterial agents of foodborne illness. It begins by defining foodborne disease as any infectious or toxic disease caused by food or water according to the WHO. It then discusses various chemical, bacterial, parasitic, and fungal hazards including toxins produced by algae, fungi, and cyanobacteria. Specific parasites mentioned are Giardia, Entamoeba histolytica, and Cryptosporidium. Prion diseases like scrapie are also summarized. Control methods focus on food inspection and safety practices.
This document discusses contamination and spoilage of canned foods. It describes how canned foods can spoil through three main mechanisms: survival of thermophilic bacterial spores due to inadequate heating; allowing germination of spores due to improper cooling or storage; and recontamination through leaks. It categorizes foods based on pH and outlines various types of biological spoilage caused by thermophilic and mesophilic bacteria, as well as by yeasts and molds. Common spoilage symptoms like gas formation, swelling, souring and black discoloration are also described.
The document discusses several types of fermented vegetables including sauerkraut, kimchi, olives, and pickles. It describes the key ingredients and processes used to ferment each vegetable. Sauerkraut is made from fermented cabbage using a process of shredding, salting, and fermenting the cabbage for several weeks. Kimchi also uses fermented cabbage but includes additional spices and a shorter fermentation time. Olives undergo a lye treatment before being fermented in brine for 6-8 months. Pickles are made by fermenting cucumbers in a brine solution for several weeks. The dominant microorganisms in each fermentation process are various species of lactic
Contamination, Preservation and Spoilage of milkAnil Shrestha
This document discusses sources of contamination and spoilage in milk and milk products. It outlines various sources of contamination on the farm, during transit and processing, including farm equipment, milking utensils, employee hands, and processing equipment. It then discusses methods of preservation like heat, cold temperatures, and preservatives. Finally, it describes different types of spoilage bacteria that can cause souring, gas production, ropiness, proteolysis, lipolysis, and flavor changes in milk, resulting in off-flavors like bitter, burnt, or unusual colors.
1. Cereals and cereal products can be contaminated with bacteria and molds from various sources like the exterior of harvested grains, the environment, and processing equipment.
2. Microbial spoilage of cereals is influenced by moisture level, temperature, and physical damage. Common spoilage microorganisms include molds, yeasts, and bacteria that can produce mycotoxins or cause odors and sourness.
3. Preservation methods to prevent cereal spoilage involve proper storage temperatures, cleaning practices, chemical preservatives, irradiation, and controlling moisture levels. Specific spoilage issues include moldiness, ropiness, and chalky or red discoloration of bread.
The document discusses foodborne infections and intoxications. Foodborne infections occur when harmful microorganisms in contaminated food grow in the intestines and cause illness, while intoxications result from toxins produced by microorganisms or present in plants/seafood. Common bacteria that can cause infections include Salmonella, Listeria, Campylobacter, and viruses like Hepatitis A and parasites such as Giardia. Symptoms include diarrhea and vomiting. Prevention methods include proper food handling and cooking practices.
The document provides an introduction to food microbiology. It discusses how microorganisms can cause food deterioration by utilizing nutrients and producing enzymatic changes. It also discusses the importance of microorganisms in food processing and preservation as well as foodborne illness and spoilage. The document then describes various microorganisms important in food, including molds, yeasts, bacteria, and viruses. It provides examples of both beneficial and spoilage microorganisms and discusses how spoilage occurs.
Foodborne diseases pose a significant threat to public health worldwide. They can be caused by bacteria, viruses, parasites or toxins entering the body through contaminated food. Major pathogens like Salmonella, E. coli and Campylobacter cause foodborne infections and intoxications with symptoms like diarrhea and vomiting. In developing countries, poor hygienic practices and lack of surveillance exacerbate the foodborne disease burden. Proper food safety practices and surveillance systems are needed to reduce illnesses and deaths from these preventable diseases.
Fermentation / fermented food / type of fermented food / microbial action Sumit Bansal
Fermentation in food processing is the process of converting carbohydrates to alcohol or organic acids using microorganisms—yeasts or bacteria—under anaerobic conditions. Fermentation usually implies that the action of microorganisms is desired.
Dr. Babasaheb Nagurao Kumbhar discusses mycotoxins, which are toxic substances produced by fungi that grow on crops. Some key points:
- Mycotoxins are secondary metabolites of fungi that are toxic to other organisms. Unlike bacterial toxins, they are not usually detectable by immune systems.
- Over 300 mycotoxins are known. Major ones of concern include aflatoxins, deoxynivalenol, zearalenone, fumonisin, T-2 toxin, and ochratoxin A.
- Factors like temperature, moisture levels, and storage conditions can favor mycotoxin production. Common toxigenic fungi
The document discusses food microbiology and methods for detecting microbes in food. It describes how microorganisms are introduced to foods and both their beneficial roles in fermentation and spoilage when conditions allow undesirable growth. Detection methods discussed include plate counts, membrane filtration, and microscopic analysis. Intrinsic food factors like pH, water activity, and natural antimicrobials and extrinsic storage conditions like temperature and atmosphere that influence microbial growth are also summarized.
Foodborne infections are caused by ingesting pathogenic microbes that penetrate the intestinal mucosa. The majority of foodborne illness is caused by microorganisms like bacteria, moulds and viruses. Foodborne infections can lead to complications like dehydration and HUS. Foodborne intoxication occurs when toxins produced by bacteria in food like C. botulinum, S. aureus, C. perfringens and B. cereus cause illness. Prevention methods include proper food handling and cooking practices.
This document discusses fermented vegetables. It begins by introducing fermentation as a process where organisms convert carbohydrates into alcohol and/or acid. It then discusses how this process is used to preserve and enhance the flavors of vegetables. Several examples of fermented vegetables are provided, such as sauerkraut, kimchi, and pickles. The document outlines the history of fermented foods and the lactic acid bacteria involved in the fermentation process. Key aspects of producing popular fermented vegetables like sauerkraut are described. Challenges in scaling up production as well as the advantages and limitations of fermented foods are summarized.
Microbial spoilage of food occurs through the growth and activity of microorganisms. Foods provide nutrients that support the growth of microbes that may naturally contaminate foods from various environmental sources. As microbes grow and metabolize nutrients in the food, they can cause undesirable changes in texture, odor, color, flavor and gas production that render the food unacceptable for consumption. The water activity and storage conditions of foods determine whether conditions are suitable for sufficient microbial growth over time to result in spoilage.
Microbial fermentation By Aneela SaleemAneelaSaleem
This document discusses different types of fermentation processes used in industry. It begins with an introduction and overview of fermentation media and microorganisms. It then describes the main types of fermentation processes - batch, fed-batch, and continuous fermentation - and factors that influence each type such as growth rate and flow rate. The document also covers solid state and submerged liquid fermentations. Important considerations for continuous fermentation are highlighted. Recent advances in fermentation technology are briefly mentioned at the end.
Food poisoning bacteria grow best at temperatures between 5°C and 60°C. This is called the Temperature Danger Zone. Keeping potentially hazardous foods cold (below 5°C) or hot (above 60°C) stops the bacteria from growing.
History of Probiotics1900s
E. Metchnikoff attributed Bulgarian rural people's increased longevity to their regular consumption of fermented dairy products such as yogurt. He proposed that lactobacilli may operate as a putrefactive agent in the GIT metabolic abnormalities that related to disease and aging.In 1953, German scientist Werner Kollath coined the term "essential elements for the healthy development of life.
In 1965, this term was used by Lilly and Stillwell Substances secreted by one organism which stimulate the growth of anotherWhat Are Probiotics?
Combination of Friendly or good live Bacteria and/or yeasts
naturally live in your body: Gut, Mouth, Urinary tract, Skin, Lungs.
found fermented foods, dietary supplements.
Prebiotics , probiotics and Benefits of Probiotics
support for digestion,
skin health,
and immunity
keep the community of microorganisms
balanced state
Different homogenization and pastruzation effect on bacillus resistance in milk Mostafa A.Shalaby
This document discusses a study that evaluated the effects of combining high homogenization pressure (HPH) and temperature on spore-forming bacteria, including B. licheniformis, B. subtilis, B. cereus, and Geobacillus stearothermophilus. The study aimed to establish alternative non-thermal methods for obtaining safe milk. Milk was inoculated with spores and subjected to various pressures (250-400 MPa) and temperatures (125-140°C) using HPH. Spore counts were determined before and after treatment to calculate reduction. The thermal resistance of spores was also measured at different temperatures before and after HPH.
Lactic acid bacteria and other microbes play important roles in food production. Lactobacillus acidophilus, L. lactis, and Streptococcus lactis in yogurt and cheese help digest milk and produce beneficial compounds. Saccharomyces cerevisiae is used to produce bread, beer, wine and other alcoholic beverages through fermentation. Microbes also have many industrial uses including producing antibiotics, organic acids, amino acids, vitamins and other chemicals. They help treat wastewater and produce biofuels and enzymes.
“Microbes matters”. Cooperation among bacteria. Good microbes. Microbes too helps us in various ways. List of uses of microbes. The reason behind tasty foods. Microbes are useful in food production and food industries. “Fermentation may have been greater discovery than fires”. Fermentation – the main job of microbes. Brewing beer, liquors and wine. The need of microbes in agriculture. It helps in encountering of insects. Microorganisms are an important part of wastewater treatment. Contribution to medicine - thousands of antibiotics known to us are made by microorganisms. The best kind of biodegradable plastics are the ones made by bacteria because they can also be broken down by bacteria. It also helps to set up your aquarium. The complex microbial communities on and in the human body can sometimes get out of balance – Maintaining of balance. Microorganisms have evolved as a potential alternate source of energy. Microorganisms are used to produce biofuels like biodiesel, bioalcohol and also microbial fuel cell. We are all here because of an organism that changed the world and also paved the way for complex life on earth – Evolution. Microorganisms help us in researching on diseases, such as in vaccination. We conclude with the a considerations of the consequences of the these complex interactions and we briefly discuss the potential role of social interactions involving multiple traits and multiple environment constraints in the evolution of specialization and division of microbes.
Bacillus sp. was isolated from the gastrointestinal tract of freshwater fish Cyprinus carpio. The document discusses optimizing protease production by this Bacillus sp. strain. It notes that proteases play an important role in cell functions and have many biotechnology and industrial applications. The effects of physical factors like temperature and pH on protease production by the isolated Bacillus sp. strain are investigated.
This document discusses microorganisms used in food fermentation. It describes the criteria for selecting microorganisms, including that they must be safe, food-grade, and approved. It also discusses the microbiology of fermented foods, including that fermentation involves microbes converting raw materials and producing end products. Common genera used in fermentation are also listed, including Lactococcus, Streptococcus, Leuconostoc, Pediococcus, and Lactobacillus. Species from these genera are frequently used as starter cultures.
Præsentation indhold er lavet af et Biotec virksomhed, og Digitypes har stået for design opsætningen. Designet er lavet så firmaet på egen hånd via Powerpoint kan ændre i designet
Food microbiology is the study of microorganisms that are present in foods and can affect food quality and safety. Microbes can be beneficial, neutral, or harmful to humans. Foods provide excellent nutrients to support microbial growth. There are many factors that affect microbial growth in foods, including intrinsic factors like pH, moisture content, and nutrients as well as extrinsic factors like temperature, relative humidity, gases, and time. Microbial spoilage of foods is evidenced by changes in appearance, texture, odor, and flavor and is caused by bacteria, molds, and yeasts growing in the food.
This document provides an overview of the genus Lactobacillus. It discusses the history of isolation of various Lactobacillus species from different sources. It covers the taxonomy, morphology, habitat, metabolism, roles in food production and as probiotics, pathogenesis, and cultural and biochemical characteristics of Lactobacillus. The document also includes images showing growth of Lactobacillus in different media and biochemical test results.
Lactic acid bacteria (LAB) such as Lactobacillus, Lactococcus, Leuconostoc, and Pediococcus are important in food fermentation processes. They produce lactic acid which preserves foods and improves safety. Lactobacillus is the largest LAB genus and includes species used in dairy, bread, meat and vegetable fermentations. Lactococcus lactis is used as a starter culture for cheeses and cultured dairy. These LAB vary in their temperature and pH preferences, as well as metabolic pathways, contributing to flavor development in fermented foods through production of organic acids, aromas, and proteolysis.
This presentation is about Probiotic and prebiotic and the role of them in our body and their benefits .
kindly if you have any inquiry contact me anytime .
Best wishes
This document discusses the taxonomy, roles, and significance of microorganisms in food. It begins by defining taxonomy and how microorganisms are classified. It then discusses how microorganisms are essential to breaking down foods into inorganic compounds. The primary sources of microorganisms in foods are identified as soil, water, plants, food utensils, humans/animals, and animal feeds. The roles of microorganisms in the dairy, cereal, meat, and color production industries are described. Finally, it discusses how microorganisms can be used to remove mycotoxins from contaminated foods.
Microbial growth is affected by several key factors:
Availability of nutrients, moisture, temperature, pH, and gaseous atmosphere. Culture media must provide appropriate levels of these factors to encourage microbial growth. Bacteria are cultured using liquid or solid media in an incubator, then examined for colony formation and characteristics. A bacterial growth curve includes lag, logarithmic, stationary, and death phases as the microbes multiply and nutrients are depleted.
This document discusses the medical applications of fermentation technology. It begins with an introduction to fermentation and how microorganisms can be used to produce useful chemicals. It then discusses the types and stages of industrial fermentation processes. Some key applications of fermentation in medicine discussed include the production of insulin, vaccines, interferons, vitamin B12, enzymes, and antibiotics. Modern fermentation allows for mass production of these substances using genetically engineered microorganisms.
The document discusses yeasts that are used as starter cultures in fermented foods. It provides background on the early history of fermentation and then discusses the properties of yeast cells. It outlines the different types of metabolisms in yeasts and how they are classified. The document then examines the various roles yeasts play in fermenting different types of foods like dairy products, meats, cereals, beverages and more. It provides examples of common yeast species used in fermenting these different food categories.
The document discusses the synergistic and antagonistic effects of microorganisms interacting in mixed cultures. Synergistic effects occur when microbes work cooperatively to produce an enhanced effect, like the interaction between Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in yogurt production. Antagonistic effects happen when microbes inhibit each other through mechanisms like pH changes, toxin production, or competition for resources. These interactions are important in food fermentation processes and can be exploited to obtain desired product characteristics or extend shelf life.
Starter cultures are microorganisms used to initiate fermentation processes and produce desirable qualities in fermented foods. They are selected based on their ability to produce acids that preserve foods while inhibiting spoilage. Factors like antibiotics, bacteriophages, residual detergents and disinfectants can inhibit starter cultures and negatively impact food quality. Proper selection and handling of starter cultures is important for producing foods with consistent quality through controlled fermentation.
Probiotics are live microorganisms that provide health benefits when consumed. Common probiotic microorganisms include Lactobacillus and Bifidobacteria species. Probiotics can help treat intestinal disorders like diarrhea and inflammatory bowel disease by competing with pathogens for binding sites and stimulating the immune system. They may also help prevent allergies and reduce the risk of certain cancers developing.
This is a presentation on the Principe and Application of ELISA in food industries explained by showing the different methods (competitive and non competitive)
Prebiotics : Characteristics and usage in food industry
Other bacteria in food industry
1. Other bacteria than
lactic acid bacteria
used as starter
cultures in food and
their properties
M. ANZA Adamou
2. introduction
– The fermentation is a bacterial process that takes place during the production
of numerous food products. It provides the final products with characteristic
aromas and textures and plays a crucial role in food safety and hygiene. Among
the bacteria responsible we have the lactic acid bacteria, which display high
morphological and physiological diversity and other non lactic acid bacteria
involved in the processes. We will present them as well as their caracteristics.
3. Bifidobacterium
– Bifidobacteria are indigenous inhabitants of the human intestinal tract, which is
one of the most complex microbial ecosystems (microbiota) on the planet,
comprising over 100 trillion bacteria in the large intestine (CABALLERO,
FINGLAS, & TOLDRA, 2016).
– Bifidobacterium is a Gram-positive, nonmotile, nonspore-forming, and
anaerobic organism. Bifidobacterial cells often stain irregularly with methylene
blue. Some species can tolerate oxygen, some are obligate anaerobes, and
some species can tolerate oxygen in the presence of carbon dioxide. These
organisms are catalase-negative; however, some species, such as
Bifidobacterium indicum and Bif. asteroides, possess weak catalase activity
when grown in the presence of air (Shah, 2011).
4. Bifidobacterium
– Bifidobacterium produces higher levels of acetic acid than lactic acid, usually in
the ratio of 3:2. These bacteria produce formic acid, ethanol, and succinic acid.
Some reports suggest that butyric acid and propionic acid are not produced.
However, studies in the author’s laboratory have shown the production of
butyric acid and hippuric acid by these microorganisms. Bifidobacterium can
grow in the temperature range of 25–45 °C, with a maximum growth
temperature of 43–45 °C and a minimum growth temperature of 25–28 °C. The
optimum temperature for growth of Bifidobacterium of human origin is
between 36 and 38 °C, whereas for those of animal origin this is between 41
and 43 °C. Growth of Bifidobacterium does not occur below 20 °C, and these
organ isms do not have thermoresistance above 46 °C (Shah, 2011).
5. Bifidobacterium
– The optimum pH for growth of Bifidobacterium is 6.5–7.0. No growth occurs
below the pH of 4.5–5.0 or above 8.0–8.5. Below pH 4.1, most species die in
less than a week even at 4 C, and below pH 2.5 most species die in less than 3 h.
Carbonate or bicarbonate can be readily used by Bifidobacterium as carbon
sources. However, Bifidobacterium cannot utilize fatty acids or organic acids as
carbon sources (Shah, 2011).
– The mean mol. % G + C of DNA for Bifidobacterium is about 58% (Batt &
Tortorello, 2014)
6. Bifidobacterium
– In the United States before the 1980s, the use of bifidobacteria in foods was limited to
a few products intended for therapeutic treatment. Among the earliest products was a
bifidus milk developed by Mayer in the 1940s for use in treatment of infants afflicted
with nutritional deficiencies. By the 1960s, enough evidence had been accumulated to
show it was possible to modify intestinal biota with B. bifidum. In the 1970s, Japan
produced its first bifidus product, a fermented milk containing B. longum and
Streptococcus thermophilus (in 1971). Bifidus yogurt followed in 1979. Growth of
bifidus foods and bifidus growth factor supplements continues to this day in Japan
with other countries of the world following suit. Products that have been formulated
with viable bifidobacteria and/or bifidus growth supplements include fermented and
nonfermented milks, buttermilk, yogurt, cheese, sour cream, dips and spreads, ice
cream, powdered milk, infant formula, cookies, candies, fruit juices, and frozen
desserts (Batt & Tortorello, 2014).
7. Propionibacterium
– Propionibacteria are pleomorphic rods, often diphtheroid or club shaped, but
may also exist as single cells, as pairs, or as branched cell aggregates; they are
anaerobic to aerotolerant and generally catalase-positive. The principal
propionibacteria associated with cheese are Propionibacterium freudenreichii, P.
thoenii, P. jensenii, and P. acidipropionici, often referred to as the dairy
propionic acid bacteria (PAB). Propionibacterium freudenreichii consists of two
subspecies, P. freudenreichii subsp. freudenreichii and P. freudenreichii subsp.
shermanii. The propionibacteria have temperature and pH growth optima at
25–32 C and 6.5–7.0, respectively. They are generally more sensitive to
conditions of high acidity than the lactic acid bacteria. Propionibacteria can
grow in the presence of 6–7% NaCl under optimum conditions, but at the low
pH found in cheese (pH 5.2–5.4) their growth rate in the presence of NaCl is
further reduced (Rattray & Eppert, 2011).
8. Propionibacterium
– Propionibacteria are essential for the development of the characteristic flavor
and eye formation in Swiss-type cheeses such as Emmental, Gruye `re, and
Appenzeller. Unlike P. camemberti, G. candidum, and B. linens, which grow on
the cheese surface, the propionibacteria grow internally in the cheese matrix.
The proteolytic activity of the dairy PAB is generally low, with a clear species
and strain variability. They grow poorly in milk, but addition of casein
hydrolysate to milk enables growth to significantly higher cell numbers (Rattray
& Eppert, 2011).
9. Brevibacterium
– Brevibacterium linens is a strictly aerobic microorganism with a rod–coccus
growth cycle, and has temperature and pH growth optima at 20–30 °C and 6.5–
8.5, respectively. Slow growth of this organism occurs in cheese-ripening
conditions, such as 12 °C and pH 5.5. It is a halotolerant microorganism, and can
grow in the presence of 15% NaCl. The growth of B. linens on the surface of
bacterial surface-ripened cheeses, such as Saint Paulin, Limburger,
and Münster, is preceded by the growth of yeasts and molds. The yeasts and
molds utilize the lactate present in the curd, and deacidification of the surface
occurs. This pH increase enables the growth of B. linens and other bacteria,
including B. casei, Arthrobacter spp., Corynebacterium spp., Micrococcus spp.,
and Staphylococcus spp (Rattray & Eppert, 2011).
10. Brevibacterium
– Brevibacterium linens produces extracellular aminopeptidases and proteinases,
the number and properties of which depend to a large extent on the strain. The
extracellular proteinases produced by B. linens are serine proteinases and are
highly active on αs1- and β-casein. In addition to these extracellular enzymes, the
presence of intracellular peptidases and proteinases has also been reported for
B. linens; however, these intracellular activities are low compared to the
extracellular activities. The production of extracellular lipolytic and esterolytic
activities by B. linens has not been determined unambiguously, with a number of
reports presenting conflicting data. However, intracellular esterases have been
detected and a number of them have been purified and characterized. One of
the most interesting and important properties from a cheese-ripening
perspective is the production of various volatile sulfur compounds, in particular
methanethiol, by B. linens (Rattray & Eppert, 2011).
11. Brevibacterium
– Brevibacterium linens is also characterized by its ability to produce various
bacteriocins and antimicrobial substances. The biochemical properties of the
bacteriocins produced by B. linens appear to be strain dependent, but at least
some of them have been shown to be inhibitory toward foodborne pathogens
such as Staphylococcus aureus and Listeria monocytogenes. Another important
property of B. linens is its unique yellow-orange aromatic carotenoid
pigmentation. The red-orange color of the surface of cheese varieties such as
Saint Paulin, Muünster, and Limburger is due primarily to the pigments
produced by Brevibacterium spp., Corynebacterium spp., Micrococcus spp., and
Arthrobacter spp (Rattray & Eppert, 2011).
12. Acetobacter
– Acetic acid bacteria (AAB) have been used for making vinegar at least since
Babylonian times. For most of this time, vinegar was obtained by fermentation
from natural alcoholic solutions (10–15% v/v ethanol) without an understanding
of the natural process. AAB belong to the family Acetobacter of the class
Acetobacteraceae. The family is classified into the former core genera,
Acetobacter and Gluconobacter, and eight genera. Species of Acetobacter (now
19 species) were partially newly classified, and a new genus was introduced,
Gluconacetobacter (16 species).
– Acetobacter are Gram-negative rods. Old cells may become Gram-variable. Cells
appear singly, in pairs, or in chains, and they are motile by peritrichous flagella
or nonmotile. There is no endospore formation (Hommel, 2014).
13. Acetobacter
– Acetobacter spp. are obligate aerobes except for Acetobacter diaztrophicus, for
example, which belongs to the diverse group of free-living aerobic or
microaerophilic diazotrophic AAB. Depending on growth substrates, some
strains may require p-aminobenzoic acid, niacin, thiamin, or pantothenic acid as
growth factors. The temperature range is 8–45 C with an optimum range
between 25 and 30 C. The optimal pH for growth is about pH 4–6.3. Acetophilic
strains have their optimum at pH 3.5, acetophobic ones at 6.5, and
acetotolerant strains can grow on both pH values. Strains used in making
vinegar are more resistant toward acidic pH values. Resistance is strain specific.
Isolates obtained from commercial submerged processes grow well at a pH of
2.0–2.3 (Hommel, 2014).
15. Acetobacter
– Acetobacter spp. are used in different processes of making foods and food
additives. Vinegar is the most popular product of Acetobacter and
Gluconacetobacter made by incomplete oxidation. From the technical point of
view, one can differentiate between slow traditional and fast submerged
processes, respectively. In traditional vinegar making, AAB grow near/at the
surface where oxygen tension is high. Acetobacter spp. are involved in a
number of natural fermentations. A typical tropical beverage, palm wine, is
made from palm sap as a result of a mixed alcoholic, lactic acid, and acetic acid
fermentation by a complex microbial consortium. Acetobacter strains have also
been isolated from cocoa wine, made by fermentation of cocoa seeds (Hommel,
2014).
16. References
– Batt, C. A., & Tortorello, M. L. (2014). Encyclopedia of food microbiology Encyclopedia of food
microbiology.
– CABALLERO, B., FINGLAS, P. M., & TOLDRA, F. (2016). ENCYCLOPEDIA OF FOOD AND HEALTH. In B.
CABALLERO, P. M. FINGLAS, & F. TOLDRA (Eds.), ENCYCLOPEDIA OF FOOD AND HEALTH (pp. 4013).
– Hommel, R. K. (2014). Acetobacter A2 - Batt, Carl A. In M. L. Tortorello (Ed.), Encyclopedia of Food
Microbiology (Second Edition) (pp. 3-10). Oxford: Academic Press.
– Rattray, F. P., & Eppert, I. (2011). Cheese | Secondary Cultures A2 - Fuquay, John W Encyclopedia of
Dairy Sciences (Second Edition) (pp. 567-573). San Diego: Academic Press.
– Shah, N. P. (2011). BACTERIA, BENEFICIAL | Bifidobacterium spp.: Morphology and Physiology A2 -
Fuquay, John W Encyclopedia of Dairy Sciences (Second Edition) (pp. 381-387). San Diego: Academic
Press.