期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1985
卷号：31
期号：1
页码：99-106
DOI：10.3177/jnsv.31.99
出版社：Center for Academic Publications Japan
摘要：Utilization and requirement of soy protein isolate (SPI) and SPI-rice combination were examined in twenty-five female students. After 1 day on protein-free diet, each subject received a low-protein diet for 10 days. The protein sources were SPI for ten subjects and SPI-rice combination, in which the ratio of two proteins was 6:4, for fifteen subjects. The nitrogen intakes were about 45, 65 and 85mg/kg in both the two series of experiments. Energy intake was at an approximate maintenance level of 36.1±3.0 kcal/kg. Apparent nitrogen balance improved with increase in nitrogen intake. The regression equations between nitrogen intake ( X , mg/kg) and balance ( Y , mg/kg) are shown in the following: SPI: Y =0.411 X -40.8 ( n =10, r =0.812) SPI and rice protein: Y =0.392 X -32.7 ( n =15, r =0.739) From the above equations, the maintenance intakes of SPI and SPI-rice combination for an apparent nitrogen equilibrium were calculated to be 99 and 83 mg N/kg, respectively. Digestibilities were 98.2±5.0% for SPI and 93.1 ±6.10 for SPI-rice combination. The NPUs of SPI at intake levels of 40, 60 and 80mg N/kg were 47±24 ( n =4), 49 ( n =2) and 44±3 ( n =4), respectively. The NPUs of SPI and rice mixed protein at intake levels of 45, 70 and 90 mg N/kg were 67±13 ( n =5), 51±7 ( n =5) and 54±12 ( n =5), respectively. It was concluded from the present study that both SPI and the SPI-rice combination had a high nutritive efficiency comparable with that of egg protein.
关键词：soy protein isolate;rice protein;soy-rice mixed protein;nitrogen requirement;NPU;slope ratio method
