Effects of High Pressure on Inactivation of Enzymes and Microorganisms in Non-Pasteurized Rice Wine (Namazake)

Abstract

Hydrostatic pressure of 1000_??_6000kg/cm² was applied to enzyme solution and Namazake (nonpasteurized rice wine) to investigate high pressure effects on inactivation of enzymes and microorganisms. The pressurization caused a partial inactivation of enzymes (α-amylase, glucoamylase, protease, serine carboxypeptidase), and after pressurization at 6000kg/cm² for 10min at 25°C, 20_??_60 percent of the original activity remained. Increasing temperature, ethanol concentration, and duration of pressurization accelerated the inactivation of these enzymes. Repeating the pressurization was also effective in increasing enzyme inactivation. Pressurization of 3000kg/cm² for 10min at 25°C sterilized the Lactobacillus and yeast in Namazake. Namazake after pressurization at 4000kg/cm² for 30min at 25°C had the same flavor as the original Namazake. This was stored for a month at 30°C and no deterioration in constituents or flavor was noted.