Proteins in dried distillers' grains with solubles: A review of animal feed value and potential non‐food uses

Abstract

Dried distillers' grains with solubles (DDGS) are the main byproduct from bioethanol production and are commonly used as livestock feed. This work aims to provide an overview of animal feed value (protein and amino acid profiles and protein fractionation approaches) and potential non‐food uses of DDGS proteins, particularly those from corn, sorghum, and wheat. Crude protein and amino acids (essential and nonessential) composition vary among different DDGS due to the variation in chemical composition of parent feedstock and processing condition. Extraction or fractionation approaches such as physical/mechanical (sieving and winnowing), chemical (ethanol, acid, and alkaline), and enzymatic (protease) treatments have been explored to isolate specific proteins of corn (zein), sorghum (kafirin), and wheat (gluten protein) from respective DDGS. In addition, valorization of DDGS proteins for biomaterials (biodegradable films and bioadhesives) was evaluated. Due to the heterogeneous nature of DDGS, multi‐stream processes with economic and environmental benefits should be taken into consideration before the commercialization of DDGS proteins. This review will benefit future research and development activities on value‐added and more specific utilizations of DDGS.

Corn distillers solubles as a novel bioresource of bioactive peptides with ACE and DPP IV inhibition activity: characterization, in silico evaluation, and molecular docking

“…All the docked peptides are in their best poses stabilized by various interactions among which the frequency of H-bond interactions was greater, followed by that of hydro-phobic-and electrostatic interactions. For example, TPPFHLPPP (13), DPANLPWG (13), and WNGPPGVF (11) had a greater number of H-bond interactions with an average distance of respective 2.99 Å, 3.12 Å, and 2.45 Å accompanied by higher total interactions (25, 24, and 22 respectively). It is interesting to mention here that the H-bonds formed by TPPFHLPPP (13), DPANLPWG (13), and WNGPPGVF (11) with ACE were more than those with lisinopril (10).…”

“…For example, TPPFHLPPP (13), DPANLPWG (13), and WNGPPGVF (11) had a greater number of H-bond interactions with an average distance of respective 2.99 Å, 3.12 Å, and 2.45 Å accompanied by higher total interactions (25, 24, and 22 respectively). It is interesting to mention here that the H-bonds formed by TPPFHLPPP (13), DPANLPWG (13), and WNGPPGVF (11) with ACE were more than those with lisinopril (10). A previous study also reported the GPAGPRGPAG peptide from smoothhound viscera PH with more H-bonds (11) than lisinopril (10).…”

“…12 Prolamins (zein) are poorly soluble in water due to the higher concentration of lipid-soluble amino acids (AAs) and are a diverse blend of disulfide-connected groups. 13 The presence of lipid-soluble AAs and yeast proteins in CDS favors the obtention of biopeptides through enzymolysis. 14 In addition, protein degradability in CDS than in DDGS can be expected to be lower because of the avoidance of high-temperature drying steps, which can damage proteins by cross-linking in the protein bodies.…”

“…Conversely, enzymolysis has been suggested as a superior method of enhancing the retrieval of less extractable and digestible proteins of corn by-products. 13 Hence, it might solve contemporary problems for CDS proteins, upgrading the contents of free AAs, polypeptides, and longer protein sequences. 3,21 The characterization of peptides using traditional techniques is costly and laborious.…”