Zymology is the branch of science which deals with fermentation. It is a metabolic anaerobic process in which complex molecules break down into simpler molecules that are utilized to generate energy in the form of Adenosine triphosphate. This process occurs in bacteria and yeast and is also found in oxygen-starved muscle cells in humans under stressed conditions. In foods, fermentation is a process that converts carbohydrates into organic acids and alcohols with the help of bacteria or yeast in an anaerobic environment.
Fermented Dairy Products
Milk has been used from ancient times to produce fermented milk products, as they offer improved digestibility, additional probiotics, unique taste, minerals and vitamins. The major benefit of fermented milk products over raw milk is their long shelf life. Raw milk from different animals was preserved by common bacterial strains i.e., Lactobacillus sp. and Streptococcus sp. These nonpathogenic lactic acid-producing bacteria effectively inhibit the growth of pathogenic bacteria and save the milk from spoilage, which allows preservation of the milk for a long time without refrigeration. In milk fermentation, microorganism utilizes milk sugar and produces lactic acid as a product, which increases the acidity of milk. Yogurt, kefir, sour cream and cheese are a few examples of fermented milk products.
Yogurt
Yogurt is an excellent source of probiotics. Curd only has one Lactobacillus, but yogurt has two types of bacteria. A culture of Lactobacillus delbrueckii and Streptococcus thermophilus bacteria is used to prepare yogurt. Yogurt has around 1 X106 CFU per gram of milk. Yogurt is excellent as a probiotic and is beneficial to human health, as it is a good source of vitamin B2, B6, B12 and calcium.
Kefir
Kefir is a fermented milk product produced from the milk of cows, sheep or goats. It is rich in many nutrients such as phosphorus, calcium, magnesium, minerals, enzymes, amino acids, Vitamin A, B1, B2, B3, B6, B9, B12, C, D and E. Lactobacillus acidophilus, Bifidobacterium bifidum, Streptococcus thermophilus, Lactobacillus delbrueckii subsp. Bulgaricus, Lactobacillus helveticus, Lactobacillus kefiranofaciens, Lactococcus lactis and Leuconostoc spp are among the probiotic bacteria found.
Sour Cream
Sour cream is prepared by adding Streptococcus lactis (lactic acid producing bacteria) in pasteurized milk cream. It contains protein, phosphorus, calcium, magnesium, potassium, vitamin A, B2, B12 and choline. Sour cream is also used with different baking products such as bread, cookies, pies and cakes.
Buttermilk
Buttermilk is also known as cultured non-fat milk or cultured low-fat milk or ‘chhaj’. It is prepared by pasteurized skim milk with the combination of desirable starter cultures like Leuconostoc dextranicum, L. citrovorum and Streptococcus lactis. Buttermilk is a good source of vitamin A, D, potassium, calcium, riboflavin and phosphorus.
Fermented Vegetables
Lacto-fermentation, a process of food preservation that also enriches nutritional content is the starting point for fermented vegetables. Because of the bacteria’s activity, the minerals in cultured foods are more easily absorbed by the body. Vitamins and enzymes that aid digestion are also produced by the bacteria. Lactobacillus fermented grains and legumes frequently consumed in India include idlis, dosas, dhoklas, vadas and kadhi. Fermented foods boost nutrient uptake from the gastrointestinal system, avoiding mineral deficiency. Tempeh, kulu, dosa, idli, chilra, kinema, sinki, sauerkraut, kimchi, miso, natto and kombucha are a few examples of fermented vegetables.
Tempeh
Tempeh is a soy-based fermented dish in which soybean is fermented by Rhizopus oligosporus or Rhizopus oryzae. It is also used as a meat substitute by vegetarians, since it contains calcium, iron, magnesium, vitamin B1, B2, B3, B6, B9 & B12 and is a full protein source. That means it contains all essential amino acids required by the human body for growth. It is not however limited to vegetarians. Tempeh is a nutritious method to increase the amount of plant-based foods in nearly any diet.
Sauerkraut
Sauerkraut is a famous food made from chopped cabbage fermentation with lactic acid bacteria (Lactobacillus brevis and Lactobacillus plantarum). Because sauerkraut is produced from cabbage, it provides many of the same health advantages as a typical leafy green. The fermenting process, on the other hand provides health advantages that are specific to sauerkraut. It contains sodium, protein, iron, copper, folate, potassium, vitamin C and K.
Miso
Miso is obtained using the fermentation of soybeans by Aspergillus oryzae, but is also prepared by the mixing of rice, rye, wheat and barley with soybeans. The Koji fermentation method is used to make miso. Protein, carbs, iron, folate, zinc, copper, manganese and sodium are found in miso.
Dhokla
Dhokla is a popular legume-cereal fermented dish that originated in Gujarat but is now popular throughout India. It is prepared with soaked chickpea and rice. Streptococcus faecalis, Pichia silvicola, Lactobacillus fermentum, Candida sp., Torulopsis candida, Torulopsis pullulans and Leuconostoc mesenteroides are responsible for developing the distinctive dhokla flavor, while yeasts create folic acid, increase batter volume and provide the dish sponginess.
Fermented Alcoholic Beverages
Fermentation refers to the metabolic process through which yeast transforms sugar into ethanol in the case of alcoholic drinks. Yeast is a kind of fungus that is used to produce alcohol. In order for fermentation to occur, you must first provide some sort of carbohydrate to feed the yeast. The end result is determined by the type of carbohydrate utilized.
Wine
Wine is an alcoholic beverage prepared mostly from grapes fermentation by yeast. The sugar in the grapes is consumed by yeast, which transforms it to ethanol. The wine produce by white grapes and red grapes is known as white wine and red wine vice-versa. Wine contains carbs, magnesium, potassium, manganese, iron, phosphorus, riboflavin, calcium, zinc, iron and vitamin B6 & K.
Beer
Beer, like any other fermented food, is a microbiological product that cannot be changed. Microbial activity is present at every stage of the manufacturing process, defining the numerous sensory qualities that contribute to the end product’s quality. While Saccharomyces fermentation of grain extracts is the most significant microbial activity in brewing, several other microorganisms have an impact on the entire process. Beer contains proteins, carbs, riboflavin, niacin, pantothenic acid, selenium, phosphorus, magnesium, folate and choline.
Tadi (Palm wine)
Tadi is an alcoholic drink produced from the sap of palmyra, date palms and coconut palms by natural fermentation. Tadi is a good source of probiotics, nicotinic acid, thiamin, vitamin C, protein and riboflavin, among other nutrients. Sugar, protein, carbohydrate, amino acid, Vitamin C, yeast, potassium, zinc, magnesium, iron, vitamins B3 and B6 are all present.
References:
Parvez, S., Malik, K. A., Ah Kang, S., & Kim, H. Y. (2006). Probiotics and their fermented food products are beneficial for health. Journal of applied microbiology, 100(6), 1171-1185.
Breidt, F., McFeeters, R. F., Perez‐Diaz, I., & Lee, C. H. (2012). Fermented vegetables. Food microbiology: fundamentals and frontiers, 841-855.
Gavrilova, N., Chernopolskaya, N., Rebezov, M., Moisejkina, D., Dolmatova, I., Mironova, I., … & Derkho, M. (2019). Advanced biotechnology of specialized fermented milk products. International Journal of Recent Technology and Engineering, 8(2), 2718-2722.
Sha, S. P., Suryavanshi, M. V., & Tamang, J. P. (2019). Mycobiome diversity in traditionally prepared starters for alcoholic beverages in India by high-throughput sequencing method. Frontiers in microbiology, 10, 348.