风干肠加工和贮藏过程中蛋白质的降解规律

以总氮、非蛋白氮、氨基酸态氮、挥发性盐基氮、游离氨基酸以及不同种类蛋白质（肌浆蛋白、肌原纤维蛋白、碱溶蛋白和碱不溶蛋白）为指标，分析研究风干肠加工和贮藏过程中蛋白质的降解规律。结果表明：风干肠加工和贮藏过程中总氮含量没有显著变化；非蛋白氮含量持续升高，从原料肉的469.4 mg/100 g增加到成品肠的786.4 mg/100 g，贮藏240 d后增加至1 256.1 mg/100 g；多肽氮和氨基酸态氮含量在加工和贮藏过程中均持续增加，挥发性盐基氮含量在风干过程中没有显著变化，在贮藏180 d后迅速增加；大部分游离氨基酸含量经过加工和贮藏均有所提高，只有半胱氨酸含量明显降低；在加工过程中，肌浆蛋白和肌原纤维蛋白含量均因降解而减少，基质蛋白含量明显增加；在贮藏过程中，肌浆蛋白含量持续降低，肌原纤维蛋白含量在贮藏前180 d无明显变化，贮藏至240 d明显减少，基质蛋白含量没有显著变化。

Pattern of Proteolysis in Air-Dried Sausages during Processing and Storage

The pattern of proteolysis in air-dried sausages during processing and storage was analyzed by the detection of total nitrogen (TN), non-protein nitrogen (NPN), amino acid nitrogen (AAN), total volatile basic nitrogen (TVB-N), free amino acids (FAA), and various proteins (sarcoplasmin, myofibrillar protein, alkali-soluble protein and alkali-insoluble protein). The results showed that the TN content did not change significantly during processing and storage. The NPN content increased from 469.4 mg/100 g in raw meat to 786.4 mg/100 g in sausages, and then to 1 256.1 mg/100 g after 240 days of storage. The contents of peptide nitrogen and AAN continued to increase during processing and storage. The content of TVB-N did not change significantly during the air-drying process, but increased rapidly after 180 days of storage. The contents of most of the FAA in raw meat increased after being processed into sausages and gradually increased during storage, while only cysteine content reduced significantly. During processing, both the contents of sarcoplasmic and myofibrillar proteins decreased due to degradation, while the content of matrix protein significantly rose. During the storage process, the content of sarcoplasmic protein continued to decrease, while the content of myofibrillar proteins showed no significant change in the first 180 days and decreased significantly on day 240, and the content of matrix proteins showed no significant change over the entire storage period.