two sources of barley DDGS, it showed that protein molecular
parameters and protein secondary structure parameters
were significantly different between each other. However,
the CLA and PCA analysis in Fig. 1b indicated that it could not
be distinguished between the two types of co-products, no
matter it was analyzed according to the first principal or the
second principal component. This may imply some close
association in protein molecular structure among these corn
DDGS or between barley DDGS, respectively. In our study, the
difference in protein molecular spectra between corn DDGS
and barley DDGS may indicate that protein molecular
structure was affected by original energy feedstock (cereals
variety); it was in accordance with previous study [35]. The
differed protein molecular profiles within 5 sources of corn
DDGS and 2 sources of barley DDGS can be mainly explained
by different processing methods in different manufactures.