# 초임계 이산화탄소에 의한 감귤쥬스 중 pectinesterase의 불활성화

• Jwa, Hi-Kyung (Department of Food Science and Technology, Cheju National University) ;
• Lim, Sang-Bin (Department of Food Science and Technology, Cheju National University) ;
• Koh, Jeong-Sam (Department of Agricultural Chemistry, Cheju National University)
• Published : 1996.08.30
• 48 7

#### Abstract

Citrus juice was treated with supercritical carbon dioxide $(SC-CO_{2})$ as an alternative to heat for pectinesterase (PE) inactivation to minimize undesirable changes in flavor, color and ascorbic acid loss caused by the current heat treatment, and the effect of temperature $(40,\;50,\;60^{\circ}C)$, pressure (138, 276 bar) and process time $(5{\sim}130\;min)$ on PE activity was determined. PE in temperature control samples was inactivated by 54% at $40^{\circ}C$ after 130 min, 84% at 50% after 60 min and 83% at $60^{\circ}C$ after 30 min treatment compared to the original juice. PE inactivation in $(SC-CO_{2})$ treated samples at 138 bar was 83% at $40^{\circ}C$ after 130 min, 88% at $50^{\circ}C$ after 20 min and 87% at $60^{\circ}C$ after 10 min. %PE inactivation due to pressure was higher at low temperature and lower at high temperature. Higher temperature, Pressure and longer process time resulted in higher %PE inactivation. Nonlinearity in the curves of PE inactivation at different temperatures and pressures indicated that at least two forms of PE existed in citrus juice with different stabilities.

#### Keywords

supercritical carbon dioxide;citrus juice;pectinesterase