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Microbial processes for the production of alcoholic beverages

Introduction 

Although beer, wine, liquor, and other lesser-known alcoholic beverages vary, they all have one thing in common. They are the byproducts of yeast fermentation, generally Saccharomyces cerevisiae or, in the case of beers, S. carlsbergensis. Yeasts, as you may recall, are not mycelial. They are a kind of single-celled fungus that reproduces asexually by budding or fission. Fermentation is a comprehensive phrase describing the process of producing alcoholic beverages, and it may be stated as

The History of Beer and Wine Production

Several civilisations have experimented with fermented drinks throughout history, depending on a system of trial and error and careful observation. Mead, or honey wine, was produced by the Greeks, Celts, Saxons, and Vikings during the Vedic period (about 1700–1100 BC). The wine was made from grapes in Egypt, Babylon, Rome, and China, whilst beer was made from malted barley. Chicha was manufactured in South America from grains or fruits, generally, maize and octli were made in North America from agave, a cactus species.

People at the time knew that storing fruits and grains in confined vessels for extended periods of time created wine and beer, but they didn’t know why. Ferment is derived from the Latin verb serve, which means to boil. The term comes from the fact that crushed grape mixes stored in huge jars generated bubbles that seemed to be boiling. It was difficult to make fermented drinks. If the combination was not left long enough, no alcohol was generated; nevertheless, if the mixture was left too long, it degraded and became unfit to drink. Temperature and air exposure were discovered to be crucial to the fermentation process by empirical observation.

Winemakers used to soften and grind the grapes with their feet before letting the mixture settle in buckets. They were able to move germs from their feet into the mixture using this way. No one recognised at the time that one of these microorganisms, yeast, a tiny one-celled eukaryotic fungus invisible to the human eye, was responsible for the alcohol created during fermentation. Researchers were now able to explore these microorganisms after several hundred years owing to high-quality lenses and microscopes.

Vinegar

Vinegar has been used in cooking, the household, and other sectors for decades due to its slightly acidic composition. It’s one among the many microbially fermented foods that have been around for thousands of years, alongside beer, wine, bread, and fermented dairy products. It’s made up of water and acetic acid.

Acetic acid bacteria of the genus Acetobacter are often employed to ferment a wide range of alcohols. Gram-negative aerobic rods, Acetobacter bacteria are Gram-negative bacteria. They are found naturally in environments where alcohol is created and may be eliminated from spoiled fruit, apple cider, and other similar goods. Bacteria create a film on the surface of these liquids because they are aerobic and need a constant supply of oxygen. Mother of vinegar is a film that may be used to start acetic fermentation in fresh alcohol solutions. Unpasteurized retail brand vinegar also contains mother of vinegar. Acetic acid bacteria are spread in the wild by vectors like fruit flies and vinegar eels.

This acetic acid fermentation requires the addition of oxygen. Vinegar is formed when an alcohol-containing solution containing Acetobacter is kept at room temperature for months. The industrial procedure may be finished in hours since the solution is bubbled and stirred with air.

Vinegar may also be made accidentally during the winemaking process. The Acetobacter overtakes the yeasts and transforms the generated alcohol into vinegar when the temperature in the fermentation tank becomes too high.

Microbes and Dairy Products

Humans have consumed fermented milk or dairy products since prehistoric times. Various strains produce a wide range of fermented products. Lactic acid bacteria are the most common bacteria that ferment lactic acid. They are classified as GRAS because of their abundance in nature, which includes mucosal surfaces of the human body, and their usage in fermented foods. Lactobacillus, Leuconostoc, Lactococcus, Pediococcus, and Streptococcus are the most common lactic acid bacteria genera. 

Lactose, the most prevalent carbohydrate in milk, is transformed by these bacteria into lactic acid and other compounds. Fermented foods are frequently thicker than milk because the acid causes the milk proteins to precipitate. The low pH and severe acidity discourage other microorganisms, notably pathogens. Certain lactic acid bacteria have the ability to produce antibacterial chemicals. Dairy products are high in protein, calcium, phosphorus, B vitamins, and other minerals.

Conclusion 

There are a number of effective microbiological techniques available. Sufficient knowledge has been obtained, as well as information on their administration and management. Microbes’ activity in such processes may be harnessed and used if they are carefully selected, coordinated, and integrated. Their use may be a more promising alternative to large-scale industrial technology imported from developed countries, which African developing economies cannot afford, maintain, or manage.

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