Study On The Changes Of Quality And Flavor Components Of Mackerel In Storage And Processing

Mackerel occupyed a major position in China’s marine fisheries economy, perishable, difficultto store and mackerel freshness had a tremendous impact on the quality. How to effectivelydetermine the freshness of the mackerel and quality changes, objective evaluation, to meet theneeds of the field of aquatic products processing, becoming the subject of industry need to beresolved.In this paper, major study of changes in the quality of the mackerel Storage and processing ofmackerel fish flavor compounds provide a theoretical reference for the processing of mackerel.The main contents include the following four parts:(1) The characteristics of the raw fish: In order to take full advantage of mackerel, thechanges of freshness and quality of mackerel at different storage conditions(room temperature,4℃and-20℃). The volatile components and physical properties of mackerel were detected byelectronic nose and texture analyzer, and volatile basic nitrogen, pH, histamine values and SDS-PAGE were determined by chemical methods. Results showed that Principal-Component-Analysis(PCA) could distinguish the mackerel which stored at room temperature and4℃and differentstorage days, while the cumulative contribution rate was only74.77%when stored at-20℃. Theparameters of mackerel showed a declining trend with storage time. Under different storagetemperatures, values of TVB-N and histamine were increased with storage time. In addition, theresults showed that frozen storage could effectively slow down the decrease of freshness duringstorage and the degradation of the protein, extended meat quality preserved period.(2) The impact of heating on the flavor of the fish: Results showed that the electronic nose candistinguish the flavor changes of mackerel fish under different heating temperatures and in thePCA analysis chart presents some characteristics of clustering. Analysis the volatile of differentmackerel fish (fresh,80℃heat and150℃heat) by Headspace-solid-phase microextraction-GC-MS, results showed that fresh mackerel and150°C mackerel smell than80°C,150°C mackerelheterocyclic compounds and trimethylamine content of38.84%is mackerel smell substances.(3) The impact of processing methods on the flavor of the fish: Study on the volatilecomponents changes of mackerel in processing by Headspace-solid-phase microextraction-GC-MS, mackerel red meat and white meat were detected between the two heated samples out of32species,41species,39species,52kinds of volatile compounds, mainly hydrocarbons and carbonylcompounds based. Analysis and evaluation of hydrocarbons, mainly in improving the overallflavor of fish, and carbonyl compounds smell of fish have a major impact, accounting for23.35%,22.47%,58.65%,33.52%. The main volatile flavor of mackerel fish including hexanal,2-hexenal,2,4-heptadiene aldehyde,2-octene aldehyde, nonanal,2,4-kuei-diene aldehydes,3,5-octadiene-2-ketone,1-penten-3-ol,1-octen-3-ol,2-ethyl-furan,2-pentyl furan and so on. Study on the changesof volatile components of mackerel in the fermentation process, these substances include esters,alcohols, hydrocarbons, and nitrogen-containing compounds, given the unique flavor of themackerel. Vinasse could reduce the content of aldehydes and ketones in the mackerel, resultsshowed that vinasse could effectively reduce the smell of mackerel.(4) The identification of the dominant bacteria in the vinasse: In the vinasse, Yeasts and lacticacid bacteria were separated and purificated by plate scribing method. According to the colonyforms and biology characteristics, the results indicated that yeast was Debaryomyces Hansenula;lactic acid bacteria was Brevibacterium.