Research on the Quality Improvement of the Dried Meat Slice by Tenderizing and Moisturizing
|Course||Agricultural Products Processing and Storage|
|Keywords||dried meat slice phosphate papain glutamine transaminase sorbitol glycerin propylene glycol shelf life|
Dried meat slice made by traditional process is hard and difficult to chew generally.Therefor, papain is commonly used to fracture connective tissue and muscle fiber to make the dried meat slice tenderized. The humectants with many hydroxyl have the ability to combine with water. Hence the humectants are applied to improve the moisture content of the dried meat slice, without improving water activity. And flavor and taste of the products will also be improved correspondingly.First, the tenderizing effects of compound phosphate and papain were studied. The results show that papain is better to the tenderness of meat. After tenderizing by papain the muscles always show too loose, brittle, rough texture and so on. So the transglutaminase is used to cross-link the tender pork. The process conditions to improve the texture of the dried meat slice with dual-enzyme are gained as follow:the amount of papain is 360 U/g, reaction time is 20 min, reaction temperature is 70℃; the transglutaminase dosage is 7 U/g, reaction time is 2.5 h, reaction temperature is 50℃. The microstructure of pork with different treatments were observed by scanning electron microscopy to verify theoretical basis of the texture’s improvement.Second, moisture isotherms of sorbitol, glycerin and propylene glycol were studied to realize their moisturizing properties. The results reveal that all the three humectants have good moisturizing effect. The quality of products was also studied such as tenderness, moisture content, water activity, product yield. The three humectants had favorable effect to improve the quality. Through the complex test, the best compound recipe to improve the texture is obtained as follow:the amount of sorbitol 4 g/100g, glycerol 3 ml/100g and propylene glycol 0.2 ml/100g.Finally, the samples without any treatment are compared with the ones under treatment by the optimization process, the latter showed a clear advantage at all aspects of quality. The two types of samples were stored at 40℃,45℃,50℃,55℃,60℃respectively, The changes of the total number of colonies were observed and the shelf life prediction models were established. The shelf life of samples without any treatment is 151 days and the shelf life of treated samples is 212 days under the storage condition of 25℃. This indicated the shelf life of treated samples prolonged significantly comparing with untreated samples.