Rahul K. Godge*, Suhas S. Siddheshwar, Sachin B. Somawanshi, Ramdas T. Dolas, Shashikant R. Pattan
Pravara Rural College of Pharmacy, Pravaranagar, Loni, Maharastra, India
E-mail: [email protected]
Fermentation is the process of chemical change caused by organism or their product, usually producing effervescent and heat. It is an ancient process dating back thousands of years. Fermentation derives from the Latin work fever meaning “to ferment.” It was the means by which bread, wine, beer, and cheese were made. The Chinese used micro-organisms in the production of yogurt, cheese, wine, vinegar, and different types of sauces. It is a powerful economic incentive for semi-industrialized countries, in their willingness to produce bio-ethanol.
Key words: Fermentation, Downstream processing, Industrial application
Fermentation is the process of chemical change caused by organism or their product, usually producing effervescent and heat. Microbiologist considers fermentation as, any process for production of product by means of culture of micro-organism. Biochemist consider fermentation as, an energy generating process in which organic compound act both electron donor and acceptor; hence fermentation is an anaerobic process where energy produced without the participation of oxygen or other inorganic acceptor. Fermentation is process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules. Fermentation can be defined as the breakdown or catabolism of organic compounds by micro-organisms under both aerobic and anaerobic conditions. This breakdown yields end products. Fermentation can help generate ATP from glucose by substrate-level phosphorylation as long as there is a supply of NAD+ to accept electrons.
If the NAD+ pool is exhausted, glycolysis shuts down.
Under aerobic conditions, NADH transfers its electrons to the electron transfer chain, recycling NAD+.
Under anaerobic conditions, various fermentation pathways generate ATP by glycolysis and recycle NAD+ by transferring electrons from NADH to pyruvate or derivatives of pyruvate.
Fermentation is an ancient process dating back thousands of years .The term “fermentation” derives from the Latin work fevere meaning “to ferment.” It was the means by which bread, wine, beer, and cheese were made. Egyptians found that uncooked dough left standing became lighter and softer. They and the Romans discovered that yeast produced lighter and leavened bread. Around 4000 BC wine was made from grape juice through a fermentation process. Beer making by the ancients came about by the soaking of barley in water, probably a serendipitous by-product of bread making. The Chinese used micro-organisms in the production of yogurt, cheese, wine, vinegar, and different types of sauces. Cheese was made by storing milk in animal skins or bladders made from animal stomachs. The bacteria and enzymes present in these containers would cause separation of casein (milk protein) to form curd. Fermented rice, vegetables, and fruits were extensively used by Ecuadorians. Not until the work of Louis Pasteur in the late 19century was it understood how the process, which to that point was based on experience and tacit knowledge, actually worked. Antony van Leeuwenhoek, a Dutch biologist in 1680 was the first to see micro-organisms in samples of fermenting beer through a microscope. Pasteur, a French chemist, discovered that yeasts convert sugars to alcohol and carbon dioxide during fermentation. Fermentation is the process by which alcoholic beverages or acidic dairy products (cheeses, yogurt) are manufactured. It is a way for a cell to obtain energy without using oxygen. During the process, complex organic substances are broken down into simpler ones. The cell (microbial or animal) obtains energy through glycolysis– the splitting of a sugar molecule to extract its electrons. The by-product of this process is excreted from the cell in the form of substances such as alcohol, lactic acid, and acetone. With advances in the science of microbiology and technologies like biotechnology, micro-organisms are exploited to produce a wide variety of products using fermentation. These include:
1. Dairy products– Cheese, yogurt
2. Beverages– Beer, wine
3. Single Cell Proteins (SCP) – SCP are a cell monoculture of bacteria, fungi, and algae. Since the cells contain large amounts of protein, SCP is used as food or food supplement for humans and cattle. It is regarded as a cheap source of dietary protein and is produced from methanol and by-products of cheese production and paper making.
4. Antibiotics– Antibiotics are one of the most important compounds produced by fermentation. Alexander Fleming in 1929 was the first to discover “penicillin”, an antibiotic. Large numbers of antibiotics are being produced now by fermentation using various bacteria and fungi.