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

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.

Automated summary

Dried distillers' grains with solubles (DDGS) are a main byproduct of bioethanol production used as livestock feed. The protein and amino acid composition of DDGS vary due to different parent feedstock and processing conditions. Various extraction methods have been explored to isolate specific proteins from DDGS, with potential non-food uses such as biodegradable biomaterials.