微波和红外处理对油茶仁油组成和稳定性影响规律

Effects of Heat Treatment on Composition and Oxidation Stability of Camellia Oil

通过微波和红外两种方式加热油茶籽,研究了油茶仁的水分、含油率以及压榨油茶仁油的水分、氧化稳定时间、分子质量组成、液质成分等的变化规律。研究结果表明,微波和红外加热均可有效去除油茶仁和油茶仁油中的水分,相比油茶仁随加热强度增大水分降低的规律,油茶仁油中水分在加热后期有略微上升。不同功率微波处理油茶籽后,油茶仁油的氧化稳定时间随加热时间上升,不同温度红外处理油茶籽后其压榨油的氧化稳定时间呈现不同的变化规律,但是加热一定时间后油的氧化稳定时间与红外加热温度正相关,相关系数为0.7761;经过不同方式加热后油茶仁油的分子质量都有上升趋势,两种加热处理后,油茶仁油中分子的分散系数在1.05~1.06之间,随加热时间的延长越来越窄,但高功率或高温处理一定时间后分子质量分布越来越分散。负模式下测到油茶仁油中含量较高的成分壬二酸,辛二酸,15,16-二羟基亚油酸,9,12,13-三羟基-反10,顺15-十八碳二烯酸,姜辣素,油酸等加热后期含量明显上升,考虑是氧化稳定性提高的主要因素;正模式下油茶仁油中主要成分为棕榈油酸,油酸酰胺,蓖麻油酸,棕榈酰胺等。本研究结果为阐明热处理提高茶油氧化稳定性的机理提供了理论依据,为生产中油茶籽物化性质的变化规律提供了基础数据。

In this paper,the camellia oleifera seeds were treated by microwave and infrared.The changes of moisture,oil content of kernels,and the moisture,oxidation induction time,molecular weight composition and liquid composition of the oil was studied.The results show that the moisture of the camellia oleifera kernel and the camellia oleifera kernel oil were effectively reduced by microwave and infrared.However,the moisture in the oil decreased with the increase of heating intensity,the moisture in the oil was regained in the later stage of heating.The oxidation induction time of the oil after microwave treatment increased with the heating time.The oxidation induction time of the oil after infrared treatment of camellia seed with different temperature showed different change rules,while the oxidation stability time of oil was positively correlated with infrared heating temperature after heating for a certain time.The correlation coefficient was 0.7761.The molecular weight of the oil rose with various heating methods.After heating treatments,the molecular dispersion coefficient of camellia oleifera kernel oil was between 1.05~1.06,which became narrower with the extension of heating time.However,the molecular weight distribution turned more dispersed after a certain time of high power or high temperature treatment.In negative mode,azelaicacid,subericacid,15,16-DiHODE,corchorifatty acid F,gingerol,and oleicacid was detected with higher contents in the oil.In positive mode,the main components detected in the oil were palmitoleic acid,oleamide,ricinoleic acid,and palmitic amide.The results of this study provided a theoretical basis for the mechanism of improving oil oxidation stability by heat treatment of camellia oleifera seeds,and basic data for the physicochemical properties of camellia oleifera seeds.