Quality Characteristics of Kochujang with Different Ratios of Rice-nuruk

쌀누룩의 혼합비율을 달리한 고추장의 품질특성

The quality characteristics of kochujang added with additives of different ratios of rice-nuruk (at 1:0.7, 1:1.0, 1:1.3) were studied. The kochujang was stored for 8 weeks at $20{\pm}3^{\circ}C$. The brix tended to increase by increasing mixing ratio of rice-nuruk in all treatments. It increased rapidly up to 4 weeks fermentation and then showed a slight change after 6 weeks. The more mixing ratio of rice-nuruk increased, the more salinity of samples decreased. The initial pH value of kochujang was 5.08-5.10., however, the pH value decreased to 4.82-4.83 after an 8 weeks of storage period. The initial acid value was 0.66-0.68 and increased from 0.66-0.68 to 0.87-0.89. It had slight reduction phenomenon in the sixth week. As the aging period passed, chromaticity such as $a^*$- and $b^*$-values decreased gradually except for $L^*$-value. The moisture content of samples decreased gradually by adding rice-nuruk. but increased by passing an aging period. The initial amino nitrogen content of sample was 304-315 mg%. It increased to 399-442 mg% during the aging period. As the aging period passed, the total cell number increased from 6.81 log CFU/mL to 7.01 log CFU/mL in the fourth week and then steadily decreased to 6.66 log CFU/mL in the eight week. Results of sensory evaluation show that, as more rice-nuruk was added, the kochujang received a lower mark. There was no significant difference in flavor in all treatments. Color and sweetness with increasing amounts of rice-nuruk showed the lowest score. Saltiness rice-nuruk at the ratio of 1:1.0 was the highest at 6.22 points. Texture scores decreased with increasing amounts of the rice-nuruk Based on these results, the overall acceptability of the 1:0.7 rice-nuruk treatment which received the highest score is considered excellent.