Quality Evaluation and Hygienic State of Korean Kokjas and Mejus

Abstract

Kokjas and mejus are known traditional starters in Korea. They were used in the production of traditional Korean sauces and alcoholic beverages. This study was to investigate the quality and hygienic state of kokjas and mejus. The samples were collected from different regions and a total of 4 kokjas and 4 mejus were purchased. They were Gwangju kokja (GJk), Andong kokja (ADk), Busan Sanseong kokja (BSk), Busan Gijang al-kokja (BGk), Andong meju (ADm), Busan Daeyeon meju (BDm), Busan Gijang meju (BGm), and Kyeongnam Hapcheon meju (KHm), respectively. The samples were evaluated on their color, moisture content, pH and enzyme activity. This study showed that the redness and yellowness values of mejus were larger than those of kokjas. All color parameters displayed no significant difference (P<0.05), with the exception of GJk and KHm on the lightness. The highest moisture contents were obtained from BSk as 8.1%, and were followed by ADk as 6.9%. GJk and KHm showed the lowest moisture contents as 3.1%. The range of pH values was shown to be 5.3-6.6. In addition, the glucoamylase and α-amylase activities of the GJk were the highest among kokjas and mejus, 1.70 U/g and 13.20 U/g, respectively. BDm showed relatively high enzyme activity among kokjas and mejus, and the activities of α-amylase, glucoamylase and protease of the BDm were 7.70 U/g, 0.45 U/g and 0.69 mg/min, respectively. The total number of aerobic bacteria was counted in the range of 4.5-7.2 log CFU/g. The lactic acid bacteria were detected only in ADm and BGm, that the total numbers of bacteria were 6.9 log CFU/g and 4.9 log CFU/g, respectively. The results of Bacillus cereus were 2.2-5.7 log CFU/g. Total coliforms and Staphylococcus aureus were in the range of 2.8-6.3 log CFU/g and 1.8-5.1 log CFU/g, respectively. The total number of yeasts and molds were in the range of 3.4-7.4 log CFU/g and 3.9-6.6 log CFU/g, respectively.

곡자와 메주는 한국의 전통적인 발효 스타터로 알려져 있다. 이들은 한국의 장과 술의 제조에 사용되어 진다. 이 연구에서는 이러한 곡자와 메주의 품질과 위생학적 상태에 대하여 연구하였다. 곡자와 메주의 샘플은 각기 다른 지역에서 구매되었으며, 곡자는 광주곡자(GJk), 안동곡자(ADk), 부산산성곡자(BSk), 부산기장알곡자 (BGk) 4종류이며, 메주는 안동메주(ADm), 부산대연메주(BDm), 부산기장메주(BGm), 경남합천메주(KHm)이었다. 곡자와 메주시료는 색, 수분함량, pH와 효소활성도를 측정하였다. 적색도, 황색도는 메주가 곡자에 비하여 높은 값을 나타내었다. GJk, KHm를 제외한 모든 시료에서의 색차는 유의적인 차이를 보이지 않았다. 수분함량은 BSk가 8.1%로 가장 높았고, 그 다음으로는 ADk가 6.9%인 반면에, GJk와 KHm이 3.1%로 가장 낮았다. pH는 모든 시료가 5.3~6.6의 범위에 존재하였다. 그리고 알파아밀라아제와 글루코아밀라아제의 활성도는 GJk가 각각 13.20 U/g, 1.70 U/g으로 가장 높은 값을 나타내었다. BDm이 알파아밀라아제, 글루코아밀라아제, 프로테아제의 활성도가 각각 7.70 U/g, 0.45 U/g, 0.69 mg/min으로 전반적으로 높은 효소 활성도를 나타내었다. 생균수의 경우 4.5~7.2 log CFU/g의 값을 나타내었고, 유산균은 ADm과 BGm에서만 6.9 log CFU/g과 4.9 log CFU/g으로 발견되었다. Bacillus cereus는 2.2~5.7 log CFU/g의 값을 나타내었고, 대장균군은 2.8~6.3 log CFU/g, 황색포도상구균은 1.8~5.1 log CFU/g의 범위를 나타내었다. 효모와 곰팡이의 수는 각각 3.4~7.4 log CFU/g와 3.9~6.6 log CFU/g을 나타내었다