묵은지의 특성 분석을 통한 묵은지 상품기준 설정에 대한 연구

Abstract

Thirty mukeunji products were collected and their characteristics, including pH, acidity, salinity, sugar, organic acids, free amino acids, and flavor compounds, were examined along with their sensory properties. The average values of pH, acidity, sugar, and salinity were pH 3.79 ± 0.25, 1.28 ± 0.24%, 9.70 ± 1.78 brix, and 2.56 ± 0.46%, respectively. Seven types of organic acids were detected at various amounts depending on the mukeunji products. Lactic acid and acetic acid were detected in all of the mukeunji products examined, with lactic acid present in the highest quantity (10,205.15 ± 3,309.35 mg/L) followed by acetic acid (2,850.18 ± 981.87 mg/L). The level of free amino acids was 1,347.94 ± 458.46 mg/100 g(average), and there were 21~34 types of free amino acids. Glutamic acid was detected in the highest quantity. Leucine, asparagine, GABA, serine, lysine, and aspartic acid were also detected in high quantities. A total of 209 volatile compounds were detected from 30 mukeunjis and 22~78 compounds were detected from each mukeunji sample. Thirteen samples with typical mukeunji flavor and taste with a reduced off-flavor were selected from the 30 products through a sensory evaluation and were subjected to an analysis of volatile compounds, which showed that allyl methyl disulfide, dimethyl trisulfide, 2-propenyl methyl trisulfide, and 5-cyano-1-pentene were typical volatile compounds. Mukeunji and over-fermented sour kimchi are often sold as mukeunji because there is no mukeunji standard. Accordingly, a standard for mukeunji should be established to advance the industry. The results of the present study can be used as basic data to establish such a standard.