초임계 이산화탄소를 이용한 미강유 생리활성물질 농축

김인환¹^,²^,^a, 윤성원¹^,², 이준수³, 이점식⁴, 김인환¹^,²^,^a^,^*

Concentration of Rice Bran Lipid Soluble Bioactive Substances Using Supercritical Carbon Dioxide

Inhwan Kim¹^,²^,^a, Sung Won Yoon¹^,², Junsoo Lee³, Jeom-Sig Lee⁴, In-Hwan Kim¹^,²^,^a^,^*

¹고려대학교 식품영양학과

²고려대학교 대학원 보건과학과

³충북대학교 식품공학과

⁴농촌진흥청 국립식량과학원

¹Department of Food and Nutrition, Korea University

²Department of Public Health Sciences, Graduate School, Korea University

³Department of Food Science and Technology, Chungbuk National University

⁴National Institute of Crop Science, Rural Development Administration

^*Corresponding author: In-Hwan Kim, Department of Food & Nutrition, Korea University, Seoul 136-703, Korea, Tel: +82-2-940-2855; Fax: +82-2-941-7825, E-mail: k610in@korea.ac.kr

These authors are not same person

ⓒ Copyright 2013 Korean Society for Food Engineering. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Oct 10, 2013; Revised: Nov 11, 2013; Accepted: Nov 15, 2013

Published Online: Nov 30, 2013

Abatract

The aim of the present study was to examine the effects of different pressure and temperature combinations on the concentrations of tocols homologues, policosanol, phytosterol, and γ-oryzanol in crude rice bran oil (RBO) using supercritical carbon dioxide (SC-CO₂). To effectively separate oily substances from bioactive substances, fatty acid ethyl esterification was performed by sulfuric acid or the lipase catalytic method. In sulfuric acid esterification, γ-tocotrienol content was decreased by ca. 50%, whereas in lipase esterification, γ-tocotrienol content was not decreased. Therefore, lipase catalytic esterification was performed for the fatty acid alkyl esterification of RBO. The fractional extraction of RBO ethyl esters was performed using SC-CO₂ in the condition of 9.62 Mpa, 10.34 MPa, or 11.03 MPa and 45°C, 50°C, or 55°C. During the fractionation of RBO using SC-CO₂, a little tocols content was extracted with fatty acid ethyl esters, but policosanol and phytosterol were not extracted. Especially, there is a high correlation (R²=0.9306) between the density of CO₂ and tocols contents extracted to the fractions. The concentration rates of tocols and phytosterol were the highest in the condition of 55°C and 9.62 MPa. Therefore, the lower CO₂ density applied, the more efficient the concentrations of tocols and phytosterol were in this study.

Keywords: rice bran oil; supercritical CO₂ extraction; tocols; γ-oryzanol; lipase esterification