Boreddy Sreenivasula Reddy, Thippareddi Harshavardhan, Froning Glenn, Subbiah Jeyamkondan
Biological Systems Engineering Dept, Univ. of Nebraska-Lincoln, Lincoln, Nebraska.
Dept. of Poultry Science, Univ. of Georgia, Athens, GA, U.S.A.
J Food Sci. 2016 Mar;81(3):E665-71. doi: 10.1111/1750-3841.13239. Epub 2016 Feb 11.
Effect of radiofrequency (RF)-assisted thermal processing on quality and functional properties of high-foaming standard egg white powder (std. EWP, pH approximately 7.0) was investigated and compared with traditional processing (heat treatment in a hot room at 58 °C for at least 14 d). The RF-assisted thermal treatments were selected to meet the pasteurization requirements and to improve the functional properties of the std. EWP. The treatment conditions were: RF heating to 60, 70, 80, and 90 °C followed by holding in a hot air oven at those temperatures for different periods ranging from 4 h at 90 °C to 72 h at 60 °C. The quality (color and solubility) and functional properties (foaming properties: foaming capacity and foam stability; and gelling properties: water holding capacity and gel-firmness) of the std. EWP were investigated. RF-assisted thermal processing did not affect the color and solubility of std. EWP at any of the treatment conditions. In general, the foaming and gelling properties of RF-assisted thermally processed std. EWP increased with an increase in temperature and treatment duration. The optimal RF-assisted treatment conditions to produce std. EWP with similar functional properties as the traditionally processed (hot room processed) std. EWP were 90 °C for ≥8 h. These optimal conditions were similar to those for high gel egg white powder (HG-EWP, pH approximately 9.5). The RF-assisted thermal pasteurization improved the gelling properties of std. EWP to the levels of HG-EWP, leading to newer applications of this functionally improved safe product. The RF-assisted thermal processing allows the processor to produce a HG-EWP from std. EWP subsequent to processing while simultaneously pasteurizing the product, thus assuring the product safety.
研究了射频（RF）辅助热处理对高发泡标准蛋白粉（std. EWP，pH约7.0）质量和功能特性的影响，并与传统加工方法（在58°C的热室中热处理至少14天）进行了比较。选择RF辅助热处理以满足巴氏杀菌要求并改善std. EWP的功能特性。处理条件为：RF加热至60、70、80和90°C，然后在这些温度下在热风烘箱中保持不同时间，从90°C下4小时到60°C下72小时不等。研究了std. EWP的质量（颜色和溶解性）和功能特性（发泡特性：发泡能力和泡沫稳定性；以及凝胶特性：持水能力和凝胶硬度）。在任何处理条件下，RF辅助热处理均未影响std. EWP的颜色和溶解性。一般来说，RF辅助热处理的std. EWP的发泡和凝胶特性随温度和处理时间的增加而增加。生产具有与传统加工（热室加工）std. EWP相似功能特性的std. EWP的最佳RF辅助处理条件是90°C持续≥8小时。这些最佳条件与高凝胶蛋白粉（HG-EWP，pH约9.5）的条件相似。RF辅助热巴氏杀菌将std. EWP的凝胶特性提高到了HG-EWP的水平，从而为这种功能得到改善的安全产品带来了新的应用。RF辅助热处理使加工者能够在加工后从std. EWP生产HG-EWP，同时对产品进行巴氏杀菌，从而确保产品安全。
