Comparison of Enzyme Activities of Commercial Salted-koji and Homemade Salted-koji.

Abstract

Many kinds of salted-koji( rice-koji soaked in salted water) for pickle preparation have cometo be sold in market recently. We assayed salt and alcohol concentrations of five commercialsalted-koji. Salt concentrations were 10.2% to 13.2% and alcohol concentrations distributedfrom 2.2% to 5.7%.In addition we assayed germination ability of koji-mold (Aspergillus oryzae) and enzymeactivities remaining in five commercial salted-koji and homemade salted-koji. Homemadesalted-koji maintained the germination ability, but no commercial salted-koji showed thegermination ability.Most of the saccharifying enzyme activities of commercial salted-koji were lower than theactivities of homemade salted-koji. On the other hand, commercial salted-koji E and D had thehighest acid protease and neutral protease activities respectively in all samples. We examinedthe effect of pasteurization and ethanol on enzyme activities by using homemade salted-koji.Many kinds of salted-koji( rice-koji soaked in salted water) for pickle preparation have cometo be sold in market recently. We assayed salt and alcohol concentrations of five commercialsalted-koji. Salt concentrations were 10.2% to 13.2% and alcohol concentrations distributedfrom 2.2% to 5.7%.In addition we assayed germination ability of koji-mold (Aspergillus oryzae) and enzymeactivities remaining in five commercial salted-koji and homemade salted-koji. Homemadesalted-koji maintained the germination ability, but no commercial salted-koji showed thegermination ability.Most of the saccharifying enzyme activities of commercial salted-koji were lower than theactivities of homemade salted-koji. On the other hand, commercial salted-koji E and D had thehighest acid protease and neutral protease activities respectively in all samples. We examinedthe effect of pasteurization and ethanol on enzyme activities by using homemade salted-koji.departmental bulletin pape