Flavor Profiling Of Marinated Beef Collected From Different Regions Of China

Marinated beef is a specialty,it is a traditional marinated meat products in China.The flavor is one of important factors for evaluating.The research focused on marinated beef samples.To study the flavor compounds of marinated beef,it is of great significance to improve the quality.Firstly,to detect the volatile flavor components in marinated beef samples,the key factors were optimized.Secondly,headspace solids phase micro-extraction coupled to gas chromatography-mass spectrometry(HS-SPME-GC-MS)was utilized for the analysis of volatile flavors in samples from five regions(Southwest,Northwest,Central China,Northern and Eastern).The contents of free amino acids and 5’-nucleotides were taken with different samples.Providing a useful reference to the flavor quality of marinated beef in the future.The results were as follows:In order to establish the most suitable method,the optimization of the extraction conditions was carried out by selecting fibers and performing single-factor experiment combined with response surface methodology.As a result,65 μm PDMS/DVB fiber was used and the extraction was conducted as follows: 2.0 g sample was treated under 70℃ for 45 min and then desorbed under 240℃.After analysis,there were 44 volatile flavor compounds identified in the target samples,including aldehydes,alcohols,ketons,ethers,esters,acids,hydrocarbons,and nitrogen and sulfur heterocyclics.Of these,aldehydes and nitrogen and sulfur heterocyclics showed higher contents,being 51.29% and 16.78%,respectively,which were then determined as the dominant volatile flavor compounds in the marinated beef under investigation.The study was performed to investigate the composition of flavor compounds in marinated beef products collected from five regions.Headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry was applied to analyze the volatile compounds in the marinated beef.The E-nose was used to describe the contribution of these components to the flavor.After analysis,a total of 58,60,71,112,98 volatile components were identified in marinated beef samples from five regions,respectively.Based on the flavor profiling,the main odor-active compounds,the characteristic odor-active compounds and the common odor were determined in five regions.According to the principal component analysis of E-nose,different marinated beef samples could be obviously distinguished from each other based on their aroma profiles.Principal component analysis of aroma-active components showed that the flavor profiles of different marinated beef samples were significantly different.The cluster analysis results showed that the aroma-active compounds could be classified as 4 clusters,each of which contained odor components from different marinated beef samples.Sensory evaluation,E-tongue and high-performance liquid chromatography techniques were applied to identify five basic tastes,free amino acids and 5’-nucleotides in different marinated beef samples.Taste activity value and the monosodium glutamate equivalent were used to evaluate the non-volatile taste compounds.The results showed that the umami and salty were the key taste in marinated beef samples.The important free amino acids were determined in the 23 investigated samples were aspartic acid,glutamic acid,arginine,alanine,and histidine,and the main taste compounds were 5’-IMP and 5’-GMP,they had a greater contribution to the marinated beef samples.The EUC of marinated beef is higher than MSG of odor threshold,which meant that the umami of the marinated beef samples was intense.