1College of Agriculture and Animal Husbandry, Qinghai University, Xining, P R China
2College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, P R China
3School of Agricultural and Wine Sciences, EH Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga 2678, Australia
Journal of Food and Nutrition Research.
2018,
Vol. 6 No. 2, 124-129
DOI: 10.12691/jfnr-6-2-9
Copyright © 2018 Science and Education PublishingCite this paper: Jinying Wang, Haiyan Zhong, Qizhi Long, Paul D Prenzler. The Pro-oxidant Activity and Composition of Polar Compound Fractions in Used Deep-frying Camellia Seed Oil.
Journal of Food and Nutrition Research. 2018; 6(2):124-129. doi: 10.12691/jfnr-6-2-9.
Correspondence to: Haiyan Zhong, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, P R China. Email:
zhonghaiyan631210@126.comAbstract
We aimed to investigate the pro-oxidant activity of polar compounds in deep-frying camellia seed oil (CO) using the accelerated oxidation test, and also to analyze the fractions and distribution of its polar compounds using high performance size exclusion chromatography (HPSEC). Our results indicated that the addition of previously isolated polar compounds to four types of CO (purified refined, unpurified refined, purified crude, and unpurified crude) reduced the oxidation induction time, which suggested that these compounds were actively pro-oxidant. This result is critical for the safe storage of refined oil, and for the quality monitoring of frying oil. Our HPSEC analysis showed that used CO contained polar compounds (TGO, TGD, ox-TGM, DG, and FFA). After 40 h of deep frying, the polymerization products (TGO and TGD), oxidative products (ox-TGM), and hydrolytic products (DG and FFA) comprised 54.63%, 33.54%, and 15.14% of the total polar content, respectively, suggesting that the hydrolysis reaction during the deep frying was weak compared to thermal oxidation polymerization. Based on this result, in combination with our measurement of the concentration of total polar compounds (TPC, 27%) and triacylglycerol polymers (TGP, 10-16%), we postulate that the frying life of CO is 32 h.
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