Comparison of physicochemical characteristics of cassava starch modified byultrasonication and oxidation with ozone

Cassava starch was modified chemically using dissolved ozone (oxidation with ozone) and physically using ultrasonication. Oxidation with ozone and ultrasonication are advanced and environmentally friendly oxidation methods. Determination of the starch oxidation method should be considered to meet consumer needs and safety. Comparison between two starch modification methods (oxidation with ozone and ultrasonication) is still limited. Therefore, this work aimed to compare two environmental-friendly methods by evaluating the carbonyl and carboxyl contents, amylose content, brightness, pasting and functional properties, spectrum profiles of Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and SEM of modified starch with ozone and ultrasonication. Oxidation with ozone was performed by combining the slurry concentration (w/w) and dissolved ozone concentration (ppm) taken in three combinations: 1:6 (0.8 ppm), 1:8 (2 ppm), and 1:10 (1.4 ppm). Ultrasonication combined amplitude (%) and duration process (min) was produced in three combinations: 60% (40 mins), 80% (10 mins), and 80% (30 mins). The results showed that the degree of oxidation and the physicochemical characteristics of cassava starch were significantly more affected by ozone than ultrasonication. However, the ultrasonication method effectively depolymerized starch, resulting in amylose content and paste viscosity almost equivalent to those achieved by oxidation with ozone. Considering the safety and environmentalfriendly methods for starch modification, both oxidation with ozone and ultrasonication can be the preferred method for obtaining starch with characteristics as needed.