The Study On Freezing,thawing And Frozen Storage Condition Influenced The Wenshi Chicken

Based on the facts that the frozen WenShi chicken made from poultry was not stable during freezing and thawing processes and frozen storage,the following studies were carried out in this work by using WenShi chicken as raw materials.The following results were achieved:1.Results showed that there was significant difference in general chemical components,protein components,amino acid components,TPA value and heat flow rate of DSC between WenShi chicken and SanHuang chicken.The ratio of between essential amino acid content and total amino acid content(EAA/TAA) was 37.7%; the ratio of between essential amino acid content and nonessential amino acid(EAA/NEAA) was 60.51%.According to the requirement of ideal model of FAO/WHO that the ratio of EAA/TAA was about 40%,while the ratio of EAA/NEAA was more than 60%.So,WenShi chicken had the high quality protein which provides the theoretical basis of using it as raw materials.2.The result indicated that contravariance ability and stability of SanHuang chicken's myosin and actin were better than WenShi chicken;but contravariance ability and stability of SanHuang chicken's myogen were worse than WenShi chicken.3.From the decrease rate of DHpeakâ… ,DHpeakâ…¡and DHpeakâ…¢in the freezing process, The denaturation degree of myosin heads was more larger than sarcoplasmic protein and myosin tails,actin after freezed.4. DSC analysis results showed that DHpeakâ… had a apparent positive correaltion with Ca2+-ATPase activity, R2 was 0.8367,the correaltion equation was y=0.7971x-0.3954.5. Based on the synthetic evaluation on the testing results of the heat flow rate of DSC, physicochemical and textural characteristics, it could be concluded that increasing the freezing rates would help to maintain the original qualities of WenShi chicken, but more faster freezing rate often results in opposite expectation.Integrated all of indexes think that the quality of WenShi chicken was the best when the freezing rate is 4.21cm/h.6. The results showed that high pressure thawing could shorten the thawing time apparently,but result in more dirp loss than traditional thawing 7. minimum drip loss was observed at 150 MPa rather than the 100 and 200Mpa8. L*,b*,â–³E had a apparent increase after high pressure process rather than traditonal thawing and had a signficant difference too(P<0.05)9.Salt-soluble protein content and actomyosin ATPase activities had a noticeable decrease during the high pressure thawing process and significant difference (P<0.05) too.Employing pressure above 100 MPa , 150 MPa caused noticeable myosin heads, actin denaturation respectively during the high pressure thawing process.The denaturation degree of sarcoplasmic protein was much smaller than myosin and actin.10.DHpeakâ… +â…¡+â…¢values had a noticeable decrease during the high pressure thawing process and significant difference (P<0.05) too11.High pressure thawing could shorten the thawing time,but the indexes of frozen WenShi chicken still had a large difference with fresh,so the method of high pressure thawing wasn't suitable for WenShi chicken.12. DSC analysis results showed that DHpeakâ…¡had a apparent positive correaltion with drip loss , R2 was 0.9374,the correaltion equation was y=0.0155x+0.2766.13.Basd on the synthetic evaluation on the testing results of the drip loss, cooking loss , salt extraactable protein content, ATPase activity, TBARS value, TVB-N value and Texture index and so on, it could be concluded that the lower frozen storage temperature was,the better quality could be obtained...