Study On The Technology Optimization And Quality Of Stewed Duck Neck In Vacuum And Low Temperature

The stewed meat products have the advantages of strong flavor and convenient use.The consumption of these products accounts for more than 40% of the total traditional meat products in China.At present,the production of marinated and sauces products in China is still mainly based on the traditional marinating method that completely relies on the experience of workers,resulting in great differences in flavor and quality of different batches of products.Moreover,experienced marinating is easy to cause overcooking,serious loss of nutritional components such as protein and fat,and low product production rate.As a new type of meat processing technology,vacuum low-temperature marinade production can effectively retain the nutrients such as water,protein,fat in meat,thereby improving the yield rate,sensory quality and flavor stability of the product.In this study,the vacuum low-temperature marinating system was used to replace traditional marinating.The effects of temperature and time of low-temperature marinating and the ratio for material and-liquid on the quality of marinated duck necks and product quality variation rule were clarified during marinating process.Hence,the low-temperature marinating technology of sauced braised duck necks was optimized,and the mechanism mechanism of vacuum low-temperature marinating on duck neck quality was preliminarily clarified.(1)By combining single factor experiment and orthogonal experiment optimization,the influence of marinating time,marinating temperature,and marinating material to liquid ratio on the sensory evaluation,yield rate,shearing force and color difference value of the marinated duck neck was studied,and the optimal processing technology of vacuum low temperature sauce duck neck was explored.When the marinating time is 8-10h,the braised duck neck was moderately tender and bright in color,and it also has a higher score.when the material to liquid ratio is 1:3,the color and flavor of braised duck neck can be improved appropriately.The optimal process parameters of braised duck neck in vacuum low-temperature sauce were as follows: the braising time was 10h,braising temperature was 65℃,and ratio of braised material to liquid was 1:3.(2)The influence of the change of marinating time on the quality indexes of the braised duck neck in the braising process was investigated,and the quality of the braised duck neck was compared with traditional sauce duck neck.Studies have found that protein denaturation and water loss mainly occur in the early stage of the marinating process(4-8h).In the middle stage of the marinating,the water retention of duck necks increased with the slight degradation of protein.The effect of marinating time on b* was not significant.In addition,compared with the traditional sauce braised duck neck,the sensory score of the braised duck necks with vacuum low temperature increased by 13.1%,the production rate increased by 24.1%,the moisture content increased by 14.4%,the protein content increased by 21.7%,and the fat content reduced by 10.7%.These results shows that the low-temperature braised duck neck in sauce is better than the traditional sauce braised duck neck in terms of nutrition,sensory and production rate.(3)The effect of heat treatment on the structure of duck neck muscle fibrillary protein under vacuum and low temperature heating conditions was investigated.The results showed that with the increase of heating temperature,the surface hydrophobicity of duck neck muscle fibrillary protein was significantly increased,the carbonyl value increased overall,and the sulfhydryl value decreased overall.The secondary structure of duck neck muscle fibrillary protein also began to change,that is,the alpha helix decreased from 31.03% to 25.11%,and the irregular helix gradually increased from 17.04% to 23.00%.These results indicates that the myofibrillar protein is transformed from regular to irregular structure,and the degree of myofibrillary protein oxidation increased.The surface hydrophobicity of duck neck muscle fibrillin showed an overall downward trend with the extension of heating time.The sulfhydryl value also showed a significant downward trend(p<0.05),and the carbonyl group value increased as a whole.However,at the later stage of heating(6-12h),the carbonyl group of protein tended to be stable,and the change trend of secondary structure of fibrillary protein in duck neck muscle was roughly the same as that in the heating process.However,at the later stage of heat treatment(8h),the structural change trend of myofibrillar protein slowed down.These results show that different heating time and temperature would affect the denaturation,polymerization and oxidative degradation of myofibril protein,and the low-temperature and long-term heating method could effectively reduce protein degeneration and oxidative damage in myofibril protein,so as to improve the quality of braised duck neck products.