Comparing the effect of four different thermal modifications on physicochemical and pasting properties of breadfruit (Artocarpus altilis) starch

The present work compared the effect of different thermal treatments namely heat-moisture treatment (HMT), microwave heating treatment (MHT), heat pressure treatment (HPT) and osmotic pressure treatment (OPT) on physicochemical and pasting properties of breadfruit starch. The results showed that all modified starches exhibited a change in granule morphology, crystalline type and relative crystallinity, pasting and functionality. HMT and HPT-treated starches displayed a loss in physical integrity of the granules. Following MHT treatment, granular structures disappeared to some extent accompanied by the appearance of small holes on the granule surface. HMT, MHT and HPT altered the X-ray diffraction pattern of the starch from B to A+B-type, whereas OPT changed the type to A-type. All modified starches exhibited a decrease in relative crystallinity as compared to the native starch. HMT, HPT and OPT induced an increase in pasting temperature and a reduction in setback. All thermal treatments reduced the peak viscosity and breakdown viscosity of native starch. OPT treatment resulted in the pronounced change of peak. breakdown and setback viscosity. All modification methods did not alter the gel strength but increased water absorption capacity of the starch. (C) All Rights Reserved