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.
Examples of these products are; cheese, alcohol and bread. Fermentation is a method of generating enzymes for industrial purposes. Fermentation involves the use of microorganisms, like bacteria and yeast to produce the enzymes. There are two methods of fermentation used to produce enzymes.