Karakteristik Fisikokimia dan Fungsional Pati Nanopartikel Ubi Jalar Ungu

Abstract

Starch nanoparticles were obtained from modified purple sweet potato starch using acid hydrolysis with different types of acids, namely citric, acetic, and lactic. The hydrolysis process was carried out by incubation in purple sweet potato starch suspension with various types of acid solutions with a concentration of 7.5% and a starch and acid ratio of 1:5 (w/w). This study used a completely random non-factorial design with four repetitions. The lower RVA values were obtained for citric acid hydrolyzed starch nanoparticles, with peak viscosity values of 2363 cP, holding viscosity of 883 cP, breakdown of 1480 cP, final viscosity of 1068 cP, setback of 185 cP, peak time of 6.60 m, and pasting temperature of 70.75 oC. The XRD data obtained showed that the crystallinity value of purple sweet potato starch was 33.78%, citric acid was 38.94%, acetic acid was 36.65%, and lactic acid was 34.98%. The TEM data obtained showed that the average particle size of purple sweet potato starch was 63 nm, citric acid was 53.85 nm, acetic acid was 49.9 nm, and lactic acid was 60 nm. The results showed that acid hydrolyzed starch had significantly different effects on the amylose content, total sugar, reducing sugar, swelling power, yield, and digestibility of purple sweet potato starch.