摘要
分析了椰子分离蛋白(CPI)起泡性、泡沫稳定性、黏度及pH、离子强度、温度和蛋白质浓度对这些功能特性的影响。结果表明,椰子分离蛋白的起泡性和黏度与大豆分离蛋白(SPI)相近;而pH、离子强度、温度等因素对椰子分离蛋白的起泡性和黏度有显著的影响。在等电点(pH4.5)附近,CPI的起泡性和黏度最小,但却表现出最高的泡沫稳定性(91.25%);低离子强度可以提高椰子分离蛋白的起泡性,但高离子强度使CPI的起泡性、泡沫稳定性和黏度都变小;在70℃时CPI的黏度最大;蛋白质浓度变大时,CPI的黏度也显著增大。
Coconut protein isolates (CPI) were prepared from defatted coconut flour by the phosphate buffer method. The foaming ability, foaming stability and viscosity of CPI were studied, and the effect on these functional properties by pH, ionic strength, temperature, and protein concentration were studied too. Soybean protein isolates was used as the control. The results showed that the foaming ability and viscosity of CPI was the same to SPI nearly, but the foaming stability of CPI was higher than SPI evidently. And the effect on foaming and viscosity by pH, ionic strength, temperature and concentration of protein was noticeable. The foaming ability and viscosity of CPI was the lowest when the pH value was between pH3.5 and 4.5, which was the isoelectric point (PI) of coconut proteins, and increased as pH away from the PI. However, the foaming stability was the highest when CPI in PI. Lower ionic strength generally increased foaming ability and foaming stability of CPI, however higher ionic strength generally decreased those Of CPI. And ionic strength generally decreased the viscosity of CPI "and SPI. The viscosity of CPI increased when temperature increased, reaching to the highest when the temperature was 70℃. The viscosity of CPI became even higher when the concentration of CPI increased. The effect of temperature and concentration on viscosity of SPI was similar to that of CPI.
出处
《热带作物学报》
CSCD
2011年第12期2358-2362,共5页
Chinese Journal of Tropical Crops
基金
公益性行业科研专项(No.200903026)
海南省自然科学基金(No.20806)
关键词
椰子分离蛋白
起泡性
黏度
PH
离子强度
Coconut protein isolates
Foaming ability
Viscosity
Influencing factors