Removal of Color Pigments From Corn Distillers Dried Grains With Solubles (DDGS) to Produce an Upgraded Food Ingredient

Processing steps including bleaching, deodorizing, and milling are imperative for improving the functionality of distillers grains in various food matrices, as well as improving consumer acceptance. Utilization of distillers grains in food products is of particular interest. Various parameters were explored for the removal of pigments, including raw DDGS (diameter 0.384) or milled DDGS (0.329 mm), number of extractions (1, 2, or 3), time (30, 60, or 90 min.), and ethanol concentration (5, 10, or 15 mL/g). Altogether, the experimental design was a 2 x 3 x 3 x 3 factorial, resulting in 54 trials, which were each replicated twice. Physical and chemical properties of the resulting DDGS were analyzed. Protein content was impacted by time and number of extractions. A decrease in lipid content resulted in an inverse increase in protein content. Lipid and pigment analysis showed similar decreasing trends, signifying that lipid contents decreased while increasing solvent extraction time, ethanol concentration, and number of extractions. Physical property analysis showed ethanol extraction to be a moderately effective bleaching technique for DDGS. Chemical property data showed that the treatments were extremely effective in reducing lipid and pigment values, while increasing protein. Effective removal of pigments can improve the color of food products containing DDGS, which can lead to greater consumer acceptability of this ingredient