Ren Jiandong, Wu Jianping
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, T6G 2P5 Alberta, Canada.
J Sci Food Agric. 2015 Oct;95(13):2595-600. doi: 10.1002/jsfa.7073. Epub 2015 Feb 12.
Phosvitin is the principal phosphoprotein in egg yolk and has great potential for use as a functional food ingredient in improving bone health. This study reports a thermal-aided extraction method without using organic solvents or non-food-compatible chemicals.
Egg yolk was two times diluted with water and then extracted by 100 g L(-1) NaCl. Effects of pH and heating temperature on the extract were examined. The phosvitin purity increased from 75.7% at pH 8.0 to 80.1% at pH 5.0 and then started to decrease, but the yield decreased at decreasing pHs. The phosvitin purity increased at increasing temperature up to 90 °C and then started to decrease at 95 °C, while the yield increased from 70 to 80 °C and then started to decline at 85 °C.
A purity of 88.0% and a yield of 23.5 g kg(-1) yolk dry matter were obtained at 90 °C. The purity and yield were comparable to or higher than those of previously methods. The method developed in this study is simple, including mainly two steps, i.e. water dilution of egg yolk and NaCl extraction with heating, and can be scaled up for industrial production.
卵黄高磷蛋白是蛋黄中的主要磷蛋白，在用作改善骨骼健康的功能性食品成分方面具有巨大潜力。本研究报道了一种不使用有机溶剂或与食品不相容化学品的热辅助提取方法。
蛋黄用水稀释两倍，然后用100 g L(-1)氯化钠提取。研究了pH值和加热温度对提取物的影响。卵黄高磷蛋白纯度从pH 8.0时的75.7%增加到pH 5.0时的80.1%，然后开始下降，但产率在pH值降低时下降。卵黄高磷蛋白纯度在温度升至90°C时增加，然后在95°C时开始下降，而产率在70至80°C时增加，然后在85°C时开始下降。
在90°C时获得了88.0%的纯度和23.5 g kg(-1)蛋黄干物质产率。纯度和产率与先前方法相当或更高。本研究开发的方法简单，主要包括两个步骤，即蛋黄的水稀释和加热氯化钠提取，并且可以扩大规模用于工业生产。
