누룩곰팡이 Aspergillus oryzae OF5-20를 이용한 쌀 품종별 고상종국제조 및 품질특성

Abstract

The quality characteristics of solid starters manufactured from two types of rice samples have been reported herein. The rice samples were inoculated with Aspergillus oryzae OF5-20. It was isolated from ‘Nuruk’, a traditional fermentation starter, and exhibited high enzyme activity. The water absorption rate of rice, the raw material, reached the maximum within 160 min at ‘Samgwang’ and in 10 min at ‘Jeonju 615’. The quality evaluation tests revealed that among the for two solid starters, ‘Samgwang’ and ‘Jeonju 615’, Samgwang exhibited a higher acidity and amino acidity. As a result of the enzyme activity according to the inoculation ratio of A. oryzae OF5-20, the α-amylase showed the highest activity in ‘Samgwang’ solid starter inoculated with 4% of A. oryzae OF5-20 and ‘Jeonju 615’ solid starter with 6% inoculation. The glucoamylase activity was 1.4 times higher when the solid starter was inoculated with 4% of the liquid fungus (‘Samgwang’, 1,592.8 unit/g) than the enzyme activity when the solid starter was inoculated with 2% of the liquid fungus (1,137.8 unit/g). Since organic acids have a high ratio of citric acid and amino acids are composed of 20 kinds, such as glutamic acid, alanine, and phenylalanine, the solid starter, according to rice varieties, showed a difference in the formation of organic acids and free amino acids. Therefore, this research is expected to contribute to the improvement of the depressed starter industry and the quality of our ‘Yakju’ by the quality uniformity of solid starter manufacture using the brewing fungus with having good enzyme activity.