Department of Food Science, University of Arkansas, 272 Young Avenue, Fayetteville, Arkansas 72703,
Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital,
800 Marshall Street, Little Rock, Arkansas 72202, and Department of Biological and Agricultural
Engineering, University of Arkansas, Fayetteville, Arkansas 72701
J. Agric. Food Chem., 1999, 47 (2), pp 411–416
DOI: 10.1021/jf9806964
Publication Date (Web): December 24, 1998
Copyright © 1999 American Chemical Society
Abstract
Rice bran protein isolate (RBPI) containing approximately 92.0% protein was prepared from
unstabilized and defatted rice bran using phytase and xylanase. The yield of RBPI increased from 34% to
74.6% through the use of the enzymatic treatment. Nitrogen solubilities of RBPI were 53, 8, 62, 78, 82, and
80% at pHs 2.0, 4.0, 6.0, 8.0, 10.0, and 12.0, respectively. Differential scanning calorimetry showed that
RBPI had denaturation temperature of 83.4 °C with low endotherm (0.96 J/g of protein). RBPI had similar
foaming properties in comparison to egg white. But emulsifying properties of RBPI were significantly
lower than those of bovine serum albumin. The result of amino acid analysis showed that RBPI had a
similar profile of essential amino acid requirements for 2−5-year-old children in comparison to that of
casein and soy protein isolate.
Key words: Rice bran; protein isolate; phytase; xylanase; functional properties
摘
要
米糠分离蛋白(RBPI)含蛋白质约 92.0%是从不稳定和脱脂米糠用植酸酶和木
聚 糖 酶 提 取 的 。 通 过 酶 处 理 该 RBPI 产 量 从 34 % 上 升 至 74.6 % 。 在 pH 值 为
2.0, 4.0, 6.0, 8.0, 10.0, 12.0 时 , 米 糠 分 离 蛋 白 中 的 氮 的 溶 解 度 分 别 为
53%,8%,62%,78%,82%,80%。差异分析表明,米糠分离蛋白在 83.4°C,
低吸热(0.96 J /克蛋白质 C 的温度)时已变性。米糠分离蛋白和蛋清相比,有相似的
起泡性。但米糠分离蛋白的乳化性能较牛血清白蛋白明显为低。氨基酸分析结果表明,
和酪分离蛋白与大豆分离蛋白的相比,米糠分离蛋白含有 2-5 岁儿童所需的必需氨
基酸类似的特征。
关键词:米糠;分离蛋白;植酸酶;木聚糖酶;功能特性
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