Effects of Process Conditions on Sardine Oil During Bleaching and Deodorization

정어리유에 대한 탈색 및 탈취조건의 영향

For use of sardine oil as an ingredient of food and feed, crude sardine oil obtained by rendering was processed to RBD sardine oil. Alkali deacidification was found to be most efficient with a concentration of 2.5N NaOH and 0.5% excess level at $75^{\circ}C$. Treatment with activated clay alone at $105^{\circ}C$ for 20 min without air admission was effective in reduction of the color intensity of the oil without any formation of the conjugated dienes and trienes of polyunsaturated fatty acids. In deodorization process, as the temperature was increased, color of the oil was to become lighter. The amount of conjugated compounds was, however, increased drastically at higher temperatures above $180^{\circ}C$ for 1hr. and content of polyunsaturated fatty acids was significantly decreased.

Rendering에 의하여 추출된 정어리 조유를 이용하여 식품 및 사료의 원료로 직접 사용할 수 있는 정제 정어리유를 제조하기 위하여 탈산, 탈색 및 탈취등의 정제 실험을 실시하였다. 4%의 산성활성백토를 가하여 $105^{\circ}C$에서 20분간 질소가스하에서 탈색하는 것이 conjugated 화합물의 생성없이 가장 효과적이었다. 탈취온도가 높을수록 conjugated 화합물의 생성이 촉진되었으며, 요오드가 및 고도불포화지방산의 함량이 감소되는 경향이 뚜렷하여 정어리유의 경유 $180^{\circ}C$ 이하에서 탈취하는 것이 바람직한 것으로 밝혀졌다.