Study And Application Of Tea Polyphenol And Anthocyanidin Improving The Oxidative Stability Of Camellia Seed Oil

In this paper,we studied the enzymatic process to lipophilize tea polyphenol and anthocyanidin with the free fatty acids in crude camel ia seed oil,both tea polyphenol lipophilized oil and anthocyanidin lipophilized oil were successfully conducted.The optimum conditions of the lipophilization process were obtained by using the response surface methodology,and the synthesis of lipophilization products were confirmed by GC-MS/LC-MS.The oxidative stability of the lipophilized oil under ambient temperature and high temperature were measured through free radical scavenging experiment and heating experiment.The lipophilized oil products were applied in crackers and their effects on the quality during storage were measured.The main conclusions are as follows:(1)According to the results of response surface methodology,the optimum conditions of lipophilization process were: tea polyphenol: reaction temperature 40 °C,reaction time 32 h,amount of tea polyphenols 5.5 mg,amount of lipase 36%;anthocyanidin: reaction temperature 40 °C,reaction time 32 h,amount of anthocyanidin 5.5 mg,amount of lipase 35.8%.GC-MS analysis revealed that the free fatty acid content in lipophilized oil decreased,and lipophilized derivatives(epicatechin oleate and epicatechin palmitate;Cyanidin-3-galactoside oleate and Cyanidin-3-galactoside palmitate)were confirmed to be synthesized in tea polyphenol lipophilized oil and anthocyanidin lipophilized oil respectively.(2)The oxidative stability of the lipophilized oil samples were measured.Compared with the oil sample before lipophilization process,the free radical scavenging ability of tea polyphenol lipophilized oil and anthocyanidin lipophilized oil had an increasement of 165.6% and 156.3%,respectively;compared with commercial camel ia seed oil,the results were 16.4% and 12.3%,respectively.To compare between the oxidation stability of crude camel ia seed oil,the lipophilized oil,and commercial camel ia seed oil,the peroxide value,anisidine value,and total oxidation value of the oils were determined after 160 °C heating.The results showed that,the lipophilization oil performed better than commercial camel ia seed oil under both ambient temperature and high temperature,suggesting that the lipophilized oil was suitable in high-temperature cooking such as frying.(3)The lipophilized oil products were applied in crackers,and accelerated oxidation experiment was conducted under 55 °C.Results showed that,content of hydroperoxides in tea polyphenol lipophilized oil crackers and anthocyanidin lipophilized oil crackers were 53.6% and 48.1% less than that of commercial oil crackers,and content of aldehydes were 51.2% and 48.7% less.The shelf life prediction model of the crackers suggested that the shelf life of commercial oil crackers,tea polyphenol lipophilized oil crackers and anthocyanidin lipophilized oil crackers under the temperature of 35 °C were 50 days,82 days and 76 days,respectively,the shelf life of lipophilized oil crackers was more than 1.5 times of that of commercial oil crackers.