Preliminary Study On Flavor And Quality Optimization Of Chongqing Butter Hotpot Seasoning

Chongqing hotpot is a popular food,and its rich taste makes people have endless aftertaste.However,some defects,such as fragrant and auxiliary materials,are slow to taste,lack complementary taste,and layered flavor in eating hotpot.It significantly limits the development space of hotpot in the food industry.In this paper,the flavor and quality of butter hotpot seasoning were studied systematically.First of all,the experiment started with butter,the essential component of Chongqing hotpot,and investigated the critical flavor substances and butter quality.Secondly,butter was used as a base oil and added auxiliary spice materials to produce alcoholized oil.This article studied the influence of frying times and storage times of alcoholized oil on volatile flavor compounds and quality.Finally,the alcoholized oil was added when frying the hotpot seasoning.The factors that affected the flavor of hotpot and physical and chemical indexes in hotpot cooking.It provided some theoretical basis and feasible methods for flavor optimization of Chongqing hotpot seasoning.The main research contents and conclusions of this experiment are as follows.(1)Physical and chemical indexes reflect the quality of butter.The result of 9brands of butter acid value was between 0.66-2.50mg/g;peroxide value was between0.04-0.20g/100 g,and moisture and volatile matter content were between 0.03-0.08%.The color of butter was pale yellow in melting state,and creamy milky white in solidification state,without impurities and rancidity.By analyzing the physical and chemical indexes of 9 kinds of butter,the butter suitable for processing hot pot were sample 5,sample 6,sample 7 and sample 9.Gas chromatography-mass spectrometry(GC-MS)detected the fatty acid composition and content of 9 brands of butter.This study identified 13 kinds of fatty acids.The proportion of Saturated fatty acids and Unsaturated fatty acids were 65%and 35%,respectively.According to the physical and chemical indexes and fatty acid analysis of butter,the butter suitable for processing butter hotpot seasoning in this experiment was selected as sample 9.The volatile components of 9 butter brands were determined by headspace solid-phase microextraction(HS-SPME)combined with gas chromatography-mass spectrometry(GC-MS)technology.Eighty-five volatile flavor compoundss were identified.The main flavor compounds are aldehydes,esters,ketones and alkanes.According to the sensory threshold and Relative odor activity value(ROAV)of butter flavor compounds,13 key volatile compounds of butter were identified.The determination of key volatile compounds showed that aldehydes contributed greatly to butter flavor,which provided theoretical basis for the later study of the flavor of butter hotpot.(2)According to the above research,butter was used as the base oil,adding spice and auxiliary materials to fry and filter to obtain alcoholized oil.To study the volatile flavor compounds and quality changes alcoholized oil with different frying times and storage times.With the increased fried times of alcoholized oil,the acid value,peroxide value,carbonyl value,and malondialdehyde increased significantly(P<0.05).After frying for the fourth time,the acid value and peroxide value exceeded the safe use standard.The L* value of alcoholized oil decreased significantly and the a* value increased significantly by colorimeter(P<0.05);The UFA content decreased significantly(P<0.05).The research showed that the quality of alcoholized oil was better within three times of frying.After frying the alcoholized oil for the third time,the amount of alcohols,terpenes,aldehydes and other aromatic compounds increased by 45.50%,57.90%,7.10% and 70.00% respectively compared with that of frying once.The principal components and comprehensive scores of alcoholized oil were determined by Principal component analysis,and it was determined that continuous frying within three times was beneficial to the formation of flavor compounds.Through the analysis of physical and chemical indexes and flavor compounds of alcoholized oil,it was finally determined that the optimal frying time of alcoholized oil was 3 times.With the increased of storage days of alcoholized oil,the peroxide value of alcoholized oil increased significantly within 10 days(P < 0.05),and there was no significant difference in acid value,carbonyl value and malondialdehyde(P > 0.05).The fatty acid content did not change regularly(P > 0.05).It indicated that the peroxide value can be used as the quality evaluation index of alcoholized oil during storage.With the automatic oxidation reaction of alcoholized oil,the number and content of volatile flavor compounds such as alcohols and aldehydes increased significantly(P < 0.05).Correlation analysis showed that volatile flavor compounds such as aldehydes,esters,alkanes and alcohols were positively correlated with peroxide value,while terpenes were negatively correlated with peroxide value.It indicated that there was a close relationship between oil oxidation and volatile flavor compounds during the storage of alcoholized oil.(3)Based on the research of alcoholized oil,the hotpot seasoning was processed by single extraction and compound production.The alcoholized oil was added to the hotpot seasoning,the best ratio of alcoholized oil to butter was 1:3.Eighty-three volatile flavor compounds were detected in the hotpot seasoning with alcoholized oil.The number of flavor compounds of hotpot seasoning with alcoholized oil increased by 43.10% compared with that without alcoholized oil(P < 0.05).It was proved that adding alcoholized oil was helpful to improve the flavor of hotpot seasoning.When exploring the influence of different types of dishes on the flavor of hotpot,the main flavor substances contributed by boiling leafy vegetables and rhizomes were alcohol compounds;The main flavor compounds contributed by boiling meat were aldehydes;The main flavor compounds contributed by boiled mushrooms were aldehydes,esters and ketones.The quality and flavor of hotpot boiled for different times were studied.The results showed that with the increased of boiling times,the acid value,peroxide value,carbonyl value and malondialdehyde increased significantly(P < 0.05),and the oil quality deteriorated after boiling for the fourth time.There was no significant difference in nitrite content(P > 0.05).It showed that all indexes met the safe eating standard within 3 times of boiling.With the increased of boiling times,there was no difference in the number of volatile flavor compounds,but the specific compounds have changed.The content of flavor compounds have changed.Correlation analysis showed that there was no significant correlation between volatile flavor compounds and boiling times,and continuous boiling has no significant effect on the formation of the overall flavor of hotpot.