Summary: | 碩士 === 台南科技大學 === 生活應用科學研究所 === 95 === The purpose of this study was to investigate the properties of liquid egg white and liquid whole egg during refrigerating and freezing and the influences of glycerol and enzyme on the functional properties of liquid whole egg, to provide the cognitive and utilization of liquid egg white and liquid whole egg to the industry. The results were summarized as follows:
1. The chemical compositions of the non-pasteurized and pasteurized liquid egg white were as follows: moisture 87.44~88.59%, ash 0.65~0.69%, crude protein 10.24~10.61%, crude fat 0.18~0.36%. The chemical compositions of the non-pasteurized and pasteurized liquid whole egg were as follows: moisture 76.43~77.34%, ash 0.84~0.94%, crude protein 11.76~13.63 %, crude fat 8.83~9.91%.
2. The pH values of non-pasteurized and pasteurized liquid egg white both did not change significantly after storage at 3±1℃ for four weeks and total plate counts were 104 CFU/g . After 8 weeks, the total plate counts were increased to 107 CFU/g and non-pasteurized liquid egg white was deteriorated but the pasteurized liquid egg white were not spoiled until 12 weeks. The foaming capacity and angel cake capacity of non-pasteurized liquid egg white were superior to that of pasteurized liquid egg white (p<0.05) no matter refrigeration or freezing stored. Frozen pasteurized liquid egg white required more time to whip to wet peak.
3. The viscosity of frozen liquid whole egg was higher than that of unfrozen sample, and that viscosities of non-pasteurized liquid whole egg were higher apparently than those of pasteurized. The sponge cake capacity of frozen liquid whole egg was lower apparently than those unfrozen sample. The addition of glycerol decreased the viscosity of frozen liquid whole egg but the sponge cake capacity was increased (p<0.05). The hydrolysis ratio of frozen pasteurized liquid whole egg increased as hydrolysis time and concentration of various enzymes (trypin, bromelain and papain )were increased, and trypsin > bromelain > papain at 0.01% concentration. The addition of enzymes decreased the viscosity of frozen liquid whole egg significantly but the sponge cake capacity was increasing (p<0.05).
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