Journal Article

Values for digestible indispensable amino acid scores (DIAAS) for some dairy and plant proteins may better describe protein quality than values calculated using the concept for protein digestibility-corrected amino acid scores (PDCAAS)

Stein, Hans H., Mathai, John K., Liu, Yanhong

2017

Overview

An experiment was conducted to compare values for digestible indispensable amino acid scores (DIAAS) for four animal proteins and four plant proteins with values calculated as recommended for protein digestibility-corrected amino acid scores (PDCAAS), but determined in pigs instead of in rats. Values for standardised total tract digestibility (STTD) of crude protein (CP) and standardised ileal digestibility (SID) of amino acids (AA) were calculated for whey protein isolate (WPI), whey protein concentrate (WPC), milk protein concentrate (MPC), skimmed milk powder (SMP), pea protein concentrate (PPC), soya protein isolate (SPI), soya flour and whole-grain wheat. The PDCAAS-like values were calculated using the STTD of CP to estimate AA digestibility and values for DIAAS were calculated from values for SID of AA. Results indicated that values for SID of most indispensable AA in WPI, WPC and MPC were greater (P<0·05) than for SMP, PPC, SPI, soya flour and wheat. With the exception of arginine and tryptophan, the SID of all indispensable AA in SPI was greater (P<0·05) than in soya flour, and with the exception of threonine, the SID of all indispensable AA in wheat was less (P<0·05) than in all other ingredients. If the same scoring pattern for children between 6 and 36 months was used to calculate PDCAAS-like values and DIAAS, PDCAAS-like values were greater (P<0·05) than DIAAS values for SMP, PPC, SPI, soya flour and wheat indicating that PDCAAS-like values estimated in pigs may overestimate the quality of these proteins.

• Publisher: Cambridge University Press
• Subject: Amino acids / Amino Acids, Essential - metabolism / animal proteins / Animals / arginine / Child, Preschool / children / crude protein / Diet / Dietary Proteins - metabolism / Dietary Proteins - standards / digestibility / Digestion / dried milk / Gastrointestinal Tract - metabolism / Glycine max - chemistry / Hogs / Humans / ileum / Ileum - metabolism / Infant / ingredients / Male / Metabolism / Metabolism and Metabolic Studies / milk protein concentrate / Milk Proteins - metabolism / pea protein / Pisum sativum - chemistry / Plant Proteins - metabolism / Plants, Edible - chemistry / protein value / Proteins / rats / Seeds - chemistry / skim milk / soy flour / soy protein / Soybean Proteins - metabolism / Swine / threonine / Triticum - chemistry / Triticum aestivum / tryptophan / Vegetable Products - standards / Wheat / whey protein concentrate / whey protein isolate / Whey Proteins - metabolism / whole grain foods