Introduction to Microbiology

• Applied Microbiology is a branch of biology that studies the enzymes related to some prokaryotes and eukaryotic microbes, proteins, applied genetics, molecular biology, etc.
• Applied Microbiology is used for society and various products like food and medicines are produced on a large scale with the help of microorganisms.
• Fermentation process is used for conversion of milk into yoghurt.
• Dairy Products like cheese, butter, cream, kefir, yoghurt, etc. are produced on a large scale from milk.
• Water content and acidity of the milk changes during formation of these products and texture, taste and flavour is improved.
• These processes are performed on a large scale with more skill.
• For production of most of the milk products, bacteria in milk itself are used; only cheese is produced with the help of fungi.
• Basic process for production of yoghurt, cheese and cream is same.
• Milk is pasteurized at the beginning to destroy unwanted microbes.
• It is then fermented with the help of lactobacilli.
• In this process, lactose sugar of the milk is converted into lactic acid and milk proteins are coagulated with the help of lactic acid.
• Besides, compounds with taste and flavour are also formed.
• Microbes that destroy the chemical pesticides in soil include bacteria, fungi, and actinomycetes.
• Reasons for avoiding the use of chemical pesticides include environmental concerns, health risks, and cost.
• Industrial Microbiology is related to commercial use of microbes in which various economic, social and environmental processes and products are included.
• Various microbial processes useful for this purpose are carried out.
• Industrial Microbiology includes various productions with the help of fermentation process like bread, cheese, wine, raw material for chemicals, enzymes, nutrients, medicines, etc.
• Industrial Microbiology also involves use of microbes for garbage management and pollution control.
• Yoghurt is a milk product produced with the help of lactobacilli (inoculant).
• For maintaining the protein content, condensed milk powder is mixed with milk to be fermented for industrial production of yoghurt.
• Milk is boiled and once it cools to warm temperature, bacterial strains of Streptococcus thermophilus and Lactobacillus delbrueckii are added to it in 1:1 proportion.
• Yeast produced for commercial use contains various useful contents like carbohydrates, fats, proteins, various vitamins, and minerals.
• Recently, use of mutant varieties of bacteria has been increased.
• Some strains are developed that will help to avoid unnecessary steps or materials.
• On storing for 3 to 12 months, semi-hard cheddar cheese is formed whereas after ripening for 12 – 18 months, very hard cheese called parmesan cheese is formed.
• Microbes have natural ability of decomposing the manmade chemicals.
• Vinegar is used in each country of the world to impart sour taste to food materials and for preservation of pickles, sauce, ketch-up, chutneys, etc.
• Cheese and Butter are also milk products, but contain active bacteria like Lactobacillus, Acidophilus, Lactobacillus casei, Bifidobacterium bifidum, etc.
• These microbes maintain the balance of intestinal microorganisms, increase the population of microbes helping the digestion and decrease the population of harmful microbes (ex. Clostridium).
• Virus-resistant varieties of bacteria are developed.
• Different types of breads are produced from flour of cereals by forming dough with the help of baker’s yeast, water, salt and other necessary materials.
• Due to fermentation of carbohydrates by yeast, sugar is converted into carbon dioxide (CO2) and ethanol.
• Chemically, vinegar is 4% acetic acid (CH3COOH).
• Lactic acid is formed due to Streptococcus that makes the proteins to gel out, giving dense consistency to the yoghurt.
• Ethanol, an alcohol, is obtained by fermentation of carbon compounds like fruit juices, maple syrup, sugar molasses, starch of the roots; with the help of yeast Saccharomyces cerevisiae.
• Compressed yeast is used in commercial bakery industry and is available in dry, granular form for domestic use.
• Freshly prepared cheese is always soft like cottage cheese, cream cheese, mozzarella cheese.
• During industrial production of milk products, strict cleanliness and sterilization is essential as bacteria can be attacked by viruses.
• Dough rises up due to CO2 and the bread becomes spongy.
• Probiotic products are available in various forms like yoghurt, kefir, sauerkraut (pickle of cabbage), dark chocolate, miso soup, pickles, oils, corn syrup, artificial sweeteners, microalgae (Sea food like Spirulina, Chlorella , Blue green algae, etc.).