Development and characterization of corn starch bioplastics containing dry sprout by-product flour

Abstract

This study aimed to develop and characterize cornstarch bioplastics containing sprouts by-product flour. Thus, we performed the technological characterization of the sprouts by-product flour of different types of sprouts (beans, alfalfa, amaranth, broccoli, radish and, predominantly, clover). Firstly, we produced sprout by-products flour with forced air circulation at 50 °C. The physicochemical analyses showed that the elaborated flour had high water retention capacity, low water solubility, and high lipid content. After that, we elaborated film-forming solutions with cornstarch (4%), glycerol (30% on corn starch content) and distilled water (sufficient quantity to 100%). The dry sprout by-product flour was added at proportions of 0 (control); 2.5%; 5%; 7.5% and 10% on corn starch base. The results of the films analyzes showed that adding flour of sprouts by-product resulted in changes of the color parameters, water solubility index and melting temperature when comparing the control film to the films with different proportions of the sprouts by-product flour. The acid and oil solubility did not show differences between the analyzed formulations. Our results show that the sprouts by-product proved to be a possible ingredient for improvement of bioplastics, aiming at the improvement of technological properties and the reuse of agroindustrial residues.