B-D-Galactosidase (B-D- galactoside galactohydrolase , E. C. 3.2.1.23) , is one of the most important enzymes used in food processing . It a specific example of a glycosidase enzyme. Many organisms naturally synthesize B- galactosidase , including microorganisms , plants and animal cells . Among these possibilities , microbial sources are the best.