SPIRIT BLUE AGAR

Description

Lipids, including fats and oils, are highly reduced. When a lipid is catabolized, it has the potential to yield more pairs of electrons per gram, and thus more energy, than either carbohydrates or proteins. This process is brought about by the enzyme lipase, and the organisms possessing the enzyme lipase are called lipolytic organisms. Growth of lipase-producing microorganisms can contribute to flavour defects in milk and high fat dairy products. Some of the free fatty acids released by the action of lipolytic enzymes have a low flavour threshold and can impart a rancid flavour at low concentrations. Spirit Blue Agar is prepared according to the formulation of Starr is recommended by APHA for detection and enumeration of lipolytic microorganisms. It is a basal medium to which lipoidal substrate is added for the detection, enumeration and study of lipolytic microorganisms. Formulations in practice before Starr which included dyes as indicators of lipolysis were sometimes inhibitory to the microorganisms. Starr showed spirit blue to be inert and an ideal indicator of lipolysis, visualized as clear halos around colonies