REDUCTION OF VOLATILE ACIDITY OF GRAPE WINES BY IMMOBILIZED LIPASE

The aim of this work is to study the enzymatic transformation of acetic acid into ethyl acetate by immobilized lipases of the fungus Rhizopus microsporus UzLT-1 obtained on the basis of silica gel and phosphatidylethanolamine to reduce the content of volatile acids in grape wines. In the work, a preparation of lipase from the fungus Rhizopus microspores was used. Lipolytic activity was measured by photocolorimetric method using rhodamine 6G as a chromophore agent. The catalytic property of lipolytic enzymes from the fungus Rh.microsporus immobilized on the surface of silica gel coated with polyamides and modified cephalin in aqueous-alcoholic media was studied. It was shown that the same lipid layer, depending on the type and chemical nature of the surface groups of the matrix for application, differently affects the activity and stability of enzymes in aqueous-alcoholic media. Lipases immobilized on synthesized sorbents showed high stability in water-alcohol media. It was found that immobilized lipase exhibits good transalkylating ability in water-alcohol media and can be used to reduce the content of volatile acids in grape wines.