Chemical composition and prediction of amino acid content of maize- and wheat-Distillers' Dried Grains with Soluble

The objective of the study reported here was to examine the relationship between the chem-ical components of maize- and wheat-Distillers’ Dried Grains with Solubles (DDGS) as wellas develop prediction equations for the individual amino acids (AA) using the crude protein(CP) content of the feedstuff. Relationship between AA and CP of maize- and wheat-DDGSand their associated probability values were determined by correlation analysis. Predictionmodels for individual AA of maize- and wheat-DDGS from CP were developed using regres-sion analysis. The chemical composition of maize- and wheat-DDGS varied among sourceswith coefficient of variation (CV) ranging from 8.5 to 53.5% for total P and Ca, respectivelyin maize-DDGS and 10.8 to 37.8% for CP and ADF, respectively in wheat-DDGS. Of the indis-pensable amino acids, Lys, Met and Trp were most variable in maize-DDGS with CV of 13.1,12.0, 10.3%, respectively, whereas Lys, Phe and Met were the most variable indispensableAA in wheat-DDGS with CV of 20.2, 17.3, and 16.9% respectively. On the average, standarderror of the estimate (SEE) was greater for models predicting AA from CP of wheat-DDGS. Formaize-DDGS, r2ranged from 0.24 to 0.66 and the SEE ranged from 0.038 to 0.169 whereasr2values ranged from 0.62 to 0.94 and SEE ranged from 0.049 to 0.158 for wheat-DDGS. Ina validation exercise using independent data, the mean absolute deviations between pre-dicted and analyzed AA values were within 10% of the predicted AA value for most of the AA.It was concluded that the AA of both maize- and wheat-DDGS can be predicted from theirCP contents but only the AA in wheat-DDGS could be predicted with acceptable accuracy.Crown Copyright © 2013 Published by Elsevier B.V. All rights reserved.