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In this experiment, Rong Guofu Sichuan-style bacon for the study, using direct vacuum-packed (A treatment: control group), add tea polyphenols (B treatment) and adding sodium erythorbate (C treatment) after the vacuum packaging of three different treatments , respectively, at 5 ℃ and -18 ℃ cold storage under, and different storage periods bacon flavor quality changes, experimental results are as follows: a low temperature storage of volatile aroma components in bacon change 1.1 refrigerated bacon volatile aroma components Changes fresh bacon volatile aroma constituents of 67 species, storage 40d, 80d and 120d three treatment groups were detected in bacon A volatile aroma components 57,56 and 75 kinds. Add tea polyphenols B treatment volatile aromatic components were 38,69 and 64 kinds; adding sodium erythorbate C treatment of volatile aroma components were 52, 68 and 63 kinds. Bacon volatile aroma compounds in hydrocarbon most, followed by ketones, aldehydes and phenols; Others include alcohols, ethers, acids and esters. However, in cold conditions, the bacon flavor substances in several characteristics have declined, which furanmethanol and guaiacol showed a significant downward trend. Three groups overall number of treatments aroma components did not change significantly (P gt; 0.05). Description Add bacon different antioxidants on changes in the composition of volatile aroma little effect. 1.2 Frozen processed bacon volatile aroma composition changes in the storage time of the trial, the total number of each treatment was irregular aroma vary, but the overall downward trend. Fresh bacon volatile components of 67 species, to the end of the storage period, A, B, C three treatment were reduced to 40, 57 total aroma and 57. Add antioxidants and aroma components between treatment groups varied between showing the overall number of significant differences (P lt; 0.05). In frozen conditions, several characteristic flavor trends inconsistent. Guaiacol phenols show a slow downward trend, indicating that frozen storage conditions, storage longer, more light smoky bacon; aldehydes content presenting a ladder downward trend; while four - hydroxybutyric acid ester reduce substances related to the increase. Two cold storage in bacon flavor components other changes 2.1 refrigerated bacon flavor composition changes other bacon fat and lean bacon moisture decreased gradually. A, B, C three processed bacon fat 14.51g/100g water content decreased from the initial to the end of the 9.16g/100g, 9.62g/100g and 10.02g/100g. A, B, C three treatment by the initial moisture content of lean bacon 54.97g/100g down to the end of the 50.87g/100g, 51.62g/100g, 49.89g/100g; marbled bacon pH value has declined, A, B , C three processed bacon fat from the initial pH value decreased to 5.94 at the end of 5.57,5.69,5.73; A, B, C three thin bacon process from the initial pH value decreased to 6.09 at the end of 5.62,5.72, 5.66; sugar trends are down then up, A, B, C three treatment bacon (fat and lean mix) reducing sugar value from the initial 0.386g/100g respectively to the end of the 0.426g/100g, 0.451g/100g, 0.455g/100g; three processed bacon (lean mixture) of sodium chloride as the storage time increases; flavor substances and free fatty acids, crude protein (lean bacon) are gradually increased, the protein content of fresh bacon was 35.214%, refrigerated storage period, A, B, C processing protein detection was 36.646%, 36.136%, 36.25%; fresh bacon free amino acid content of 0.466g/100mL, after refrigeration, A, B, C treatment were detected 0.540g/100mL, 0.628g/100mL, 0.620g/100mL. These changes caused the bacon sweet, salty, fresh flavors such as changes in the storage period. 2.2 Other frozen processed bacon flavor frozen phase composition changes moisture content also show a downward trend, A, B, C three treatments bacon fat from the initial 14.51g/100g water content decreased to the end of the 9.58g/100g , 10.62g/100g and 9.87g/100g; A, B, C three kinds of processing from the initial moisture content of lean bacon 54.97g/100g down to the end of the 46.18g/100g, 50.97g/100g, 49.41g/100g ; frozen storage period, bacon pH changes more complicated. Some bacon fat, pH value decreased and then increased slightly, and finally show a downward trend, some lean bacon, three deal with bacon pH values decreased and then increased; reducing sugars (fat and lean mix) trends with cold stage, A, B, C three bacon sugar processing from the initial value, respectively, to the end of the 0.386g/100g 0.489g/100g, 0.450g/100g, 0.467g/100g; storage period, the three groups treated bacon sodium chloride (fat and lean mix) The content with storage time increases; protein (lean bacon) slow rise content, protein content of fresh bacon 35.214%, frozen storage period, A, B, C to protein detection was 38.237% , 38.081%, 38.061%; fresh bacon, free amino acids (lean bacon) content 0.466g/100mL, after frozen, A, B, C, respectively processing the detection 0.658g/100mL, 0.636g/100mL, 0.666g / 100mL; these changes caused the East hide a variety of bacon flavor variations. 3 Cold Storage in bacon texture and sensory quality changes 3.1 refrigerated bacon textural and sensory quality changes in refrigerated conditions, under different treatment conditions during storage bacon hardness and chewiness of an upward trend, while the bacon elasticity and cohesiveness sex tended to decrease. Show under refrigerated conditions, antioxidants bacon texture change to a certain extent, the mechanism needs further study. Sensory evaluation results showed that three kinds of processing and storage of bacon significant difference (P lt; 0.05), and the addition of an antioxidant treatment group score better than the group without adding anti-oxidants, polyphenols added bacon score better than adding sodium erythorbate group, bacon, bacon texture analysis which is similar to the results. 3.2 Frozen processed bacon texture and sensory quality changes in refrigerated conditions, under different treatment conditions during storage bacon hardness and chewiness of an upward trend, while the bacon elasticity and cohesiveness are showing a downward trend. In frozen conditions, the quality of tea polyphenols on bacon protection superior to sodium erythorbate, but the texture of tea polyphenols on bacon protection mechanism needs further study. Sensory evaluation results showed that three treatments during storage sensory scores were significant changes (P lt; 0.05), and the addition of an antioxidant treatment group score better than the group without adding anti-oxidants, polyphenols added score better than bacon Add sodium erythorbate group bacon, which result is consistent with the texture analysis. 4 bacon flavor changes in the mechanism of low temperature storage temperature during storage, bacon fat degradation, increased free fatty acids, POV and AV slowly increased. While at low temperatures, fat oxidation rate slows down, but it would still generate some short-chain aliphatic aldehydes and ketones. These volatile aldehydes and ketones bacon aroma is an important part of it may be excessive when stored rancid bacon flavor the main reason.
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