Coitus interruptus, also known as the withdrawal. method, is the oldest form of male contraceptive. method to be practiced.[1] It involves the male partner. pulling out the penis before ejaculation.[1] Even though. it is the oldest method of male contraception to be. practiced, research has given it very little attention.
Updated September 18, 2016. Fermentation is an energy-yielding anaerobic metabolic process in which organisms convert nutrients (typically carbohydrates) to alcohols and acids (lactic acid and acetic acid). Fermentation is perhaps the most ancient biotechnological discovery.
1 The glucose is converted to ethanol, through a process called fermentation. 2  Fermentation is a series of chemical reactions that convert sugars to ethanol. 3  The fermentation reaction, which is caused by yeast or bacteria that feed on the sugars, produces ethanol and carbon dioxide.4  Pentose Fermentation. The glucose is converted to ethanol, through a process called fermentation. 2  Fermentation is a series of chemical reactions that convert sugars to ethanol. 3  The fermentation reaction, which is caused by yeast or bacteria that feed on the sugars, produces ethanol and carbon dioxide. 4  Pentose Fermentation.