Hot Water Combined With Ultra-high Pressure Rejuvenates Frozen Beef

Beef is very popular because of its delicious taste and rich nutrition.Especially it is a indispensable cooking materials of Chinese residents.According to the survey,in recent years,the yield of beef is in short supply and the import of beef is increasing year by year in China.Freezing is one of the main ways to import beef.Frozen beef is thawed causing higher juice loss rate,the meat color browning and the quality of meat softer by the existing thawing method.Ultra-high pressure(UHP)thawing,a new type of thawing technology,which can improve meat quality,reduce the loss rate and sterilize the thawing products,but the UHP defrosting can also accelerate the browning of meat and whitening after thawing.In order to create a thawing method that can make beef thawed like fresh beef,that is means to achieve the effect of rejuvenating,the author has studied the technology of quicking frozen fresh beef,which used calcium lactate and hot water combined with ultra-high pressure technology for protecting color of beef,The main research conclusions are as follows:1)Hot water combined with UHP to improve the thawing rate,reduce the loss of juice,keep meat color,and improve the tenderness of mea.tThe optimum technology of hot water combined with UHP for rejuvenating frozen beef was 40 ? of hot water,150 MPa of pressure,40 min of dwell time Under this condition,compared with 200 MPa thawing,the thawing time decreased by about 25%,the juice loss rate increased by about 13.44%,the chroma value L* decreased by about 18.89%,the chroma value a* increased by about 139.81%,and the hardness value decreased by about 17.5%;Compared with the normal-thawing beef samples,the juice loss rate was reduced by about 10%,the meat chroma value a* was increased by about 7.49%,the chroma value L* was increased by about 10.55%,and the hardness was reduced by about 50%;compared with fresh meat,The juice loss rate increased by about 13%,the chroma value a* of the meat color increased by about 5.98%,the chroma value L* increased by about 35.93%,and the hardness value increased by about 16%.The thawing method can effectively inhibit the recrystallization.2)UHP combination with calcium lactate and hot water can enhance the color protection.The optimal process for calcium lactate protecting color: calcium lactate concentration is 0.06 mg/L,soaking time is 6 s,calcium lactate solution temperature is 40?.Under this condition,compared with the optimal of the second chapters the best technology,color stability was improved by 46.55% and the total color difference ?E with the fresh beef decreased by 47.05%.3)UHP combination with calcium lactate and hot water can improve the activity of Metmyoglobin reductase(Met Mbase).After synergistic lactate color protection,the hot water synergizes with the UHP enhanced Met Mbase activity,the optimal conditions is the 35?of hot water temperature,200 MPa of pressure,35 min of holding time;Under this condition,the activity of Met Mbase was significantly increased,is 25 times of fresh beef,3.3 times of the Met Mbase activity after a single hot water combination with UHP process conditions.4)UHP combination with calcium lactate and hot water can enhance the effect of bactericidal of beef.The optimal process: when the size of lumps is 1 kg,0.06 mg/L concentration of calcium lactate,calcium lactate solution impregnation time is 6 s,40?of temperature,the ratio of water to meat is 1:1,40?of hot water,150 MPa of pressure,40 min.of dwell time.Frozen beef according to the process conditions after thawing,3.5 d the total number of colonies required to meet the "GB 16869-2005 fresh,frozen poultry products." Through sensory evaluation,frozen beef by UHP combination with calcium lactate and hot water was approached fresh beef in all aspects and overall acceptability and better than fresh beef during storage.