Study On The Effect Of Oiland Frying Condition On The Flavor Of Fried Tilapia

Tilapia is favored by consumers because of its rich nutrition,delicate meat and no bone spurs.Fried tilapia is one of the ways of deep processing of tilapia,and volatile flavor substances play a vital role in the overall flavor.In this study,the quality and volatile flavor compounds of five edible oils,peanut oil,soybean oil,corn oil,tea seed oil and palm oil,were analyzed.The relationship between volatile substances and fatty acids was found.Five kinds of edible oil were used to fry tilapia,and the volatile compounds of fried tilapia were analyzed to find the key volatile compounds of fried tilapia.Tilapia was fried with soybean oil,and the difference in the flavor of fried Tilapia under different heating conditions is analyzed,revealing the way of flavor formation of fried Tilapia,in order to improve the flavor quality of fried Tilapia and the deep processing of Tilapia for reference.Among the five edible oils,peanut oil has the highest acid value and the deepest color value.Peanut oil has unique key flavor compounds pyrazine compounds.The volatile components of peanut oil are significantly different from other edible oils.Camellia seed oil has the highest oleic acid content(620.66 mg/g),and its volatile matter has a higher content of aldehydes.The odor profile of camellia seed oil was similar to that of peanut oil.The composition of unsaturated fatty acids in soybean oil and corn oil was relatively similar,but corn oil had the highest content of linoleic acid(425.24 mg/g);palm oil had the highest proportion of saturated fatty acids(43.85 %);soybean oil,corn oil and palm oil had relatively small differences in odor and low concentration.Among the five edible oils,gas chromatography-mass spectrometry(GC-MS)identified 86 compounds.The key flavor compounds were hexanal,nonanal and heptanal.The changes in quality and flavor of five edible oils during heating were analyzed,using a single factor method.When the heating temperature rises to140 ? and the heating time is 6 hours,the proportion of unsaturated fatty acids in the five edible oils was reduced,and saturated fatty acids were increased.The oleic acid content of camellia seed oil decreased significantly,the elaidic acid content increased,the acid value increased,and the color value deepened.The content of elastin and oleic acid was significantly correlated,and the content of linoleic acid was significantly correlated with the content of oleic acid.When the heating conditions were 140 ? and 0.5h,the volatile components of the five edible oils changed significantly,including the increase of aldehydes and the decrease of peanut oil's peculiar pyrazines.During the heating process,the correlation analysis of 44 aldehydes and ketones and three unsaturated fatty acids(oleic acid,linoleic acid and linolenic acid)among the five volatile substances in edible oil showed that:The two aldehydes were significantly positively correlated with linolenic acid(p<0.05).Six aldehydes and one ketone were significantly positively correlated with linoleic acid.Hexanal and(E)-2-heptenal had a very significant correlation with linoleic acid(p<0.01),and the correlation coefficients were 0.972 and 0.988.Four aldehydes had a significant positive correlation with oleic acid,and these four aldehydes had a significant negative correlation with linoleic acid.GC-IMS was used to analyze five volatile substances in edible fried fish.The experimental results found that the camellia seed oil fried fish was significantly different from other edible fried fish,and the difference was mainly aldehydes and alcohol compounds.Ninety-four compounds were detected in five kinds of volatile substances in fried fish,which were analyzed by SPME-GC-MS.Fresh tilapia,peanut oil fried fish,soybean oil fried fish,corn oil fried fish,camellia seed oil fried fish and palm oil fried fish were detected with 34,51,58,48,53 and 52 volatile components,respectively.Five kinds of edible fried fish were analyzed by GC-MS data combined with relative odor activity value(ROAV),and 12 common characteristic flavor substances and 6common key flavor substances were obtained.The six compounds were3-methylbutanal,hexanal,nonanal,1-octen-3-ol,2-pentylfuran and3-ethyl-2,5-dimethylpyrazine.The main characteristic flavors were fried,clear,mushroom,grilled and roasted.The overall characteristic flavors of the five edible fried fish were found to be different.In addition to the unique flavor compounds in the samples,the flavor was mainly caused by the difference in the relative content of volatile flavor substances in different edible fried fish.In the process of repeated use of soybean oil,the flavor of fried tilapia was more stable than fried in other edible oils.After being deep-fried and heated in soybean oil,the moisture,free amino acid,IMP and GMP content of fresh tilapia decreased,and the AMP content increased.The number and relative content of alcohols in volatile compounds decreased,the number of aldehydes increased,and the number and relative content of pyrazines increased.Aldehydes and pyrazines increase the oily,grilled and roasted taste of fried tilapia.Under different frying conditions,a total of 20 characteristic flavor compounds of fried tilapia were detected,and a total of 7key flavor compounds were detected.The 7 types were 3-methylbutanal,hexanal,heptanal,nonanal,(E,E)-2,4-decadienal,1-octen-3-ol and2-pentylfuran.The results show that adjusting the frying conditions could adjust the relative content and relative activity of key odor compounds to optimize their flavor.According to the results of GC-MS analysis of volatile flavors and combined with the results of ROAV analysis,the best frying condition for frying tilapia at 180 ? was selected for 4 minutes.