일부 시판 즙장의 품질 특성 및 항산화 활성

Quality Characteristics and Antioxidant Activities of Commercial Jeupjang

Jeupjang has long been considered only a local delicacy. So, it has gradually been forgotten because its name and definition have not been established. This study was performed in order to provide some basic data by comparing the general components, color, free amino acids, free sugar, organic acids and antioxidant activities between commercial Jeupjang(GG, GD, JM, NJ, NS). Moisture contents, crude protein, crude fat and crude ash contents of Jeupjang were 48.07~61.77%, 4.08~10.53%, 3.92~4.64%, and 3.63~9.95%. pH, titrable acidity and salt in Jeupjang were 4.32~5.50, 9.37~14.82 mL(1N-NaOHmL), and 3.27~8.90%. Amino-type nitrogen content is 42.05~ 138.83mg%. Lightness(L), redness(a) and yellowness(b) values in color of Jeupjang were10.04~21.89, 18.92~28.80, and 17.16~37.56. The total content of free amino acids in commercial Jeupjang ranged from 35.22mg% to 306.02mg% in which it showed wide variation among samples. The major free amino acids were glutamic acid, aspartic acid, alanine and proline. The major free sugars were fructose(0.31~1.60%), glucose(6.20~ 13.61%) and maltose(7.34~10.01%). The major organic acids were succinic acid(29.08~ 103.62 mg%) and citric acid(3.08~108.69 mg%). Total polyphenol contents were from 1.16 mg/g to 1.78 mg/g, DPPH radical scavenging activity is from 0.57 AEAC to 1.53 AEAC and ABTS radical scavenging activity is from 1.58 AEAC to 2.85 AEAC. This result might cause the differences of soybean composition, processing methods and brewing periods. For the succession of traditional fermented food such as Jeupjang, quality standards are required. To this end, the standardization of manufacturing processes must be followed.