Abstract

The quality changes of vegetables including cucumbers, young pumpkins, carrots, radishes, onions by different cooking methods in $90^{\circ}C$ water, 0.5% NaCl solution, 1.0% NaCl solution and $400^{\circ}C$ superheated steam were investigated. The changes in pH of cooked vegetables were increased. Hunter color system values for L(lightness), a(redness) and b(yellowness) of the vegetables cooked in $400^{\circ}C$ supetbeated steam for 30 seconds were less compared with those in $90^{\circ}C$ water, 0.5% NaCl solution and 1.0% NaCl solution. The microbial growth was inhibited very effectively when the vegetables cooked in $400^{\circ}C$ superheated steam for 30 seconds. After cooked in $90^{\circ}C$ water, 0.5% NaCl solution, 1.0% NaCl solution, $400^{\circ}C$ superheated steam, vitamin C content decreased by different ratio depending on cooking methods and vegetable varieties. Based on the results of the quality changes of cooked vegetables, the superheated steam cooking method showed a positive effect on sterilization and maintaining pH, color, hardness of vegetable tissues, vitamin C content. The data obtained from this study could be utilized as basic information for the optimum conditions of superheated steam cooking to develope HMR(Home Meal Replacement).

$90^{\circ}C$의 물, 0.5% NaCl 용액, 1.0% Nacl 용액, $400^{\circ}C$ 과열수증기 등을 사용하여 가열 조리한 오이, 애호박, 당근, 무, 양파 등의 채소류의 품질변화를 살펴보았다. 가열에 의한 채소류의 pH는 증가하는 경향을 보였다. 가열조리한 채소류의 색 변화를 Hunter 색차계를 사용하여 L값(밝기), a값(적색도), b값(황색도)을 측정한 결과 $400^{\circ}C$ 과열수증기로 30초간 처리한 채소류의 색변화가 $90^{\circ}C$의 물, 0.5% NaCl 용액, 1.0% Nacl 용액에서 처리한 것보다 L값(밝기), a값(적색도), b값(황색도)등의 변화가 적어 변색이 적게 일어난 결과를 나타내었다. 채소류에 존재하는 오염 미생물은 $400^{\circ}C$ 과열수증기로 30초간 처리한 채소류에서 매우 효과적으로 생육이 억제되었다. 가열조리에 의한 비타민C의 함량 변화는 조리방법과 채소류의 종류에 따라 비타민C 잔존율에 차이가 있었다. 고온의 과열수증기를 이용한 단시간 조리법은 $900^{\circ}C$의 물, 0.5% NaCl 용액, 1.0% NaCl 용액 등에서 처리한 일반 가열조리법에 비하여 pH, 색, 세포연화, 비타민C 감소율 등의 변화가 적게 나타났다. 본 논문의 연구 자료는 앞으로 진행될 가정 대용식(HMR, Home Meal Replacement)의 개발에 이용될 것이다.

Keywords

• blanching;
• supetheated steam;
• cooked vegetables;
• HMR(Home Meal Replacement);
• vitamin C content;
• vegetable texture;
• microorganism growth