Abstract

The authors isolated koji mold from the leaves of Nurushi (Rhus javanica: hereafter referred to as “Nurude”) and used this koji mold to produce soybean miso. The general composition of the soybean miso was made was measured and found to be as follows: moisture content 45.2 g/100g, protein content 16.0 g/100g, fat content 8.6 g/100g, ash content 19.0 g/100g, and carbohydrate content 11.2 g/100g. Although this soybean miso had a short maturation period of only three months, it had a high protein content and a high glutamic acid content of approximately 230 mg/100g, and its color suggested that it was sufficiently matured. Compared to soybean miso listed in the Standard Tables of Food Composition in Japan, the mineral content of the Nurude soybean miso was higher in magnesium, zinc, and copper. When the titration acidity was measured, acidity I was 10.00 and acidity II was 11.00, suggesting high content of both organic acids and amino acids. The polyphenol content of the Nurude soybean miso was 595 mg/100 g, and its antioxidant activity by the DPPH radical scavenging method was 212 μmol Trolox/100 g.

Keywords

Rhus javanica, Nurude, soybean miso, koji mold of Aspergillus oryzae, fermentation, food, functionality