Effect Of High Pressure Treatment On Texture, Salt Pickling Process Of Beef And Storage Characteristic Of Spiced Beef

Beef is a kind of luxury food and very popular all over the world which possesses the characteristics of high protein, low fat and delicious taste. Spiced beef is one of Chinese traditional low-temperature meat products. It is of good taste and flavor and easy to serve. However, it’s easy to produce secondary pollution during cutting and packaging so as to shorten shelf life because of its rich nutrition, high water activity and suitable environment for growth microorganism. As a new processing technology which is under continuous development in recent years, high pressure can improve the quality of meat products as well as prolong the storage period on the premise of having little effect to flavor and nutritional components. In this thesis, beef and spiced beef was taken as the material to investigate the effects of high pressure and temperature on structure and physical-chemical property of beef, effect of high pressure treatment on salt pickling process and quality of beef and effect high pressure and temperature treatment on storage characteristic on spiced beef.1. Uniform design was applied to examine the effects of high pressure (100-600MPa,5-30min) and temperature (20-60℃) on structure and physical-chemical property of beef. The results showed that springiness was increased by pressure (100-600MPa) and certain temperature (20-54.3℃). The pH value increased with the increasing pressure (75-450MPa) under41.6℃while the effects of pressure and temperature are not additive. Lightness was increased as pressure, holding time and temperature increased, which was similar to cooked rate. At the same time, pressure could lead to accretion of hardness while holding time and temperature had the opposite effect on hardness.2. Uniform design was applied to examine the effects of high pressure (75-450MPa,10-60min) on pH value, color, NaCl content and texture of beef during marinating. The results showed that the process of curing was accelerated by high pressure and NaCl content was increased. The pH value and lightness increased with the increasing pressure (75-450MPa), redness tend to be stable under a certain range (150-300MPa,20-50min) while hardness increased under a high level of pressure (300-450MPa). After regression analysis,223.5MPa,26.3min was selected as the optimum conditions for marinating beef.3. Quadratic general rotary design was applied to examine the effects of high pressure (200-500MPa,10-30min) and temperature (20-60℃) on sterilizing conditions of spiced beef. The results showed that the rise of pressure (200-500MPa) and temperature (20-60℃) could improve sterilization rate as well as TB A value which may lead to the decrease of quality. The sensory evaluation was in a higher level under certain treatment and reached a maximum at the condition of409.1MPa,15.5min and27℃. The optimization calculation showed that the optimum condition of high pressure and temperature treatment was454.7MPa,16.8min and45.5℃.4. Under the optimum condition of high pressure and temperature treatment and storied at4℃for10weeks, the microbial count of spiced beef was still lower than the specified value of national hygienic standard. Lactic acid bacteria and pseudomonas were dominant spoilage organisms. During the storage period, the sensory quality of spiced beef was at a good level, TBA value and TVB-N value first increased and then decreased while pH value decreased continuously.