Physicochemical, microbiological, and sensory characteristics of soy sauce fermented in different regional ceramics

Korean traditional soy sauce was fermented for 120 days in ceramics obtained from five different regions in Korea. The average internal and external temperatures of soy sauce in ceramics were 20.0 and 18.3 degrees C, respectively. Physicochemical, microbiological, and sensory characteristics were analyzed. Ceramics from different regions generated differences in physicochemical characteristics. Soy sauce fermented in the southwest regional ceramic, which has a low height and wide circumference, had significantly lower salt content, higher reducing sugar content, and protease activity rather than others. In descriptive analysis, soy sauce fermented in the ceramic from Seoul capital region had a lower intensity of saltiness and biting taste, whereas the soy sauce in the southwest ceramic had comparable saltiness and biting taste attributes as those in the southeast and central regions, and Jeju Island ceramics. Five regional ceramics were categorized into three groups by principal component analysis. Based on the physicochemical characteristics, soy sauces from southwest and Seoul capital regions had distinctive characteristics in comparison with the soy sauces from Jeju Island, southeast, and central regions.