Quinoa wet-milling: Effect of steeping conditions on starch recovery and quality

Cereal starches play an important role in the food and non-food industries because of their low cost, availability, and ability to impart a wide range of techno-functional properties. The main objective of this research was to isolate starch, germ, protein, and fiber components from quinoa by a wet-milling procedure. The effect of steeping time and temperature on starch recovery and its quality was investigated. The quinoa steeping conditions, such as time (1, 5, and 9 h) and temperature (30, 40, and 50 degrees C), in SO2 solution with lactic acid were investigated using a 3(2) factorial design in order to optimize the starch separation and its quality. The effect of steeping conditions on starch was evaluated in terms of whiteness, protein, lipid, amylase, and damaged starch contents, as well as thermal and pasting properties. Results showed how the different steeping times and temperatures affected the fraction yields and starch recovery and its quality. Optimization of the wet-milling process used in this study produced the highest starch recovery level and best starch quality after 6.5 h of steeping at 30 degrees C. Experimental values were close to the predicted ones, with an error below 2% for all attributes tested.