Microstructure and physicochemical characteristics of modified taro starch after annealing, autoclaving-cooling and heat moisture treatment

• Published in: Food Research (Online) Vol. 4; no. 4; pp. 1226 - 1233
• Main Authors: Setiarto, R.H.B., Kusumaningrum, H.D., Jenie, B.S.L., Khusniati, T., Widhyastuti, N., Ramadhani, I.
• Format: Journal Article
• Language: English
• Published: 01-08-2020
• ISSN: 2550-2166; 2550-2166
• DOI: 10.26656/fr.2017.4(4).079

This study investigated the effects of annealing, autoclaving-cooling and heat moisture
treatment on the microstructure and physicochemical characteristics of taro starch. The
taro starch was treated by the annealing process (24 hrs, 50oC), the heat moisture
treatment (HMT) (moisture 25%, 3 hrs, 110oC), and the autoclaving (15 mins, 121oC) -
cooling (24 hrs, 4oC) with 1 and 2 cycles. The results show that the autoclaving-cooling 2
cycles (AC-2C) changed the microstructure of taro starch into a very compact and dense
structure because of formed double helix bound that cannot be hydrolyzed by pancreatic
enzymes so it can be converted became resistant starch as the prebiotic source. Pasting
properties analysis showed that AC-2C improved shear stress resistance, heat resistance
and low retrogradation modified taro starch (MTS). The AC-2C treatment increased water
binding capacity (73.84%), solubility (44.58%), and swelling power (16.71%) of MTS.
The water-binding capacity had a positive correlation with solubility and swelling power.
The AC-2C treatment increased amylose content (27.40%) and decreased reducing sugar
level (6.36%) of MTS, so it can encourage the formation of resistant starch to improve the
prebiotic properties of taro starch. Modified taro starch AC-2C is the best compared to
HMT and annealing based on microstructure and physicochemical characteristics.