향류식 초임계 이산화탄소를 이용한 간장의 처리 및 천연 기능성 물질 첨가에 따른 품질 특성

Abstract

The quality characteristics of soy sauce were studied using continuous countercurrent supercritical carbon dioxide (CC-SCO₂) at various conditions. The functional compounds extracted from natural resources such as crab shell, brown seaweed and wasabi by SCO₂ was added to the soy sauce recovered after SCO₂ extraction and the soy sauce containing functional compounds were investigated for quality characteristics and antioxidative activity. The extraction column of 1,200 mm height and 19 mm I.D. was used as a spray and packed with rasching ring modes respectively. Treatment conditions of a raw soy sauce were temperature(35, 45℃), pressure(100, 170 bar), the sort of column and the change of continuous phase. Off-flavors of soy sauce were identified at different conditions. During the storage period, the treated soy sauce was examined for chemical and micro-organisms properties such as amino nitrogen, browning, buffer action and total bacterial count, Bacillus. sp., yeast. And then natural functional compounds (astaxanthin, fucoxanthin and allyl isothiocyanate) extracted from the natural resources(crab shell, brown seaweed and wasabi) by SCO⒫ were added to the treated soy sauce. The soy sauce containing functional compounds were examined for chemical properties and antioxidative activity . In the treatment of soy sauce using CC-SCO₂, there are no considerable change in chemical properties, but crude lipids were decreased by the removal of lipid from soy sauce. In case of change in free amino acid, there is a little difference. The off-flavors in soy sauce were decreased by CC-CSO₂ treatment. Especially, indole and butyric acid which are main off-flavor in soy sauce were removed completely. The soy sauce treated at 45℃, 100 bar, spray column was most effective in aspect of decreasing of flavor of soy sauce. During storage period, the soy sauce treated by the spray column was lower than that of untreated soy sauce in the microbial change, but the soy sauce treated by the packed column was higher than that of untreated soy sauce. In chemical change of the soy sauce was evaluated as improvement in quality. In the soy sauce containing large amount of natural functional compounds showed higher antioxidative activity in comparison with the that of small amount. Resulting of quality properties in the soy sauce treated by CC-SCO⒫ and containing natural functional compounds, the soy sauce was slightly improved in quality. The sensory characteristics of the soy sauce treated by SOC2 was improved by removal of off-flavors. In this study, it was founded that the antioxidant activity of the soy sauce containing functional compounds was higher than non-containing soy sauce.