Biotechnology is the art and science of converting reactants (substrate) into useful products by the action of microorganisms or enzymes. Microorganisms have been honestly serving the mankind. Thus, any process in which microbes or living organisms play a vital role in getting transformation of the feed into useful products is termed as BIOPROCESSING. For example, the way of converting milk into curds, or fruit juice into wines, or sugar into alcohol.BIOCHEMICAL ENGINEERING is of more recent origin, since the biological industries did not recognize the importance of engineering inputs until the experience of penicillin manufacture.