Effect of Cross‐linking with Epichlorohydrin on the Properties of Cassava (Manihot esculenta Crantz) Starch

Abstract

Cassava starch was cross‐linked with epichlorohydrin (EPI) at 45°C for 2 h in three different media which include water, water in the presence of a phase transfer catalyst (PTC) and N,N‐dimethylformamide (DMF). The products were characterized by determining their physicochemical, thermal and retrogradation properties. In aqueous medium, the use of a PTC, tetrabutylammonium bromide (TBAB) produced derivatives with higher degree of cross‐linking than those prepared without the use of the catalyst. The degree of cross‐linking was found to be higher using the same concentration of EPI when the reaction was carried out in DMF. At low levels of cross‐linking, the peak viscosity of the cross‐linked starches increased in comparison to that of the native starch. With increasing degree of cross‐linking, the peak viscosity showed a significant reduction. The swelling volume, solubility and light transmittance of the starch pastes were lower for the modified starches. The cross‐linked starches showed slightly reduced values for the gelatinization temperatures, Tonset, Tpeak and Tend. The enthalpy of gelatinization of the modified starches increased with increase in the degree of cross‐linking. The modified starches exhibited higher water‐binding capacities (WBC) than the native starch; but with increase in the degree of cross‐linking, there was a gradual decrease in WBC. The in vitro alpha amylase digestibility of the modified starches decreased gradually with increase in the level of cross‐linking.

Effect of Cross-Linking on Physicochemical and in Vitro Digestibility Properties of Potato Starch

“…The results were consistent with those of cross-linked cassava starch (Jyothi et al, 2006), waxy maize starch (Hirsch and Kokini, 2002), and taro starch (Hazarika and Sit, 2016).…”

Physicochemical properties of chemically modified starches from different botanical origin

“…The degree of cross-linking of the modified starches was determined from the RVA viscosity values are also presented in Table 1. It was observed that at lower level of EPI (0.3%), the degree of cross-linking of rice and maize starch was not detectable by the viscosity method, the degree of cross-linking of theses starches was not great enough to restrict the swelling of the granules and these exhibited higher peak viscosity values than that of the native starch (Jyothi et al, 2006). However the degree of cross-linking of cross-linked and oxidized cross-linked potato starch was detectable (60.1 and 20.0, respectively), higher level of cross-link of potato starch retarded the swelling of granules, resulting in a lower peak viscosity.…”

“…Singh et al (2007) observed decrease in retrogradation rate and increase in gelatinization temperature with cross-linked starch, and these phenomena are related to the reduced mobility of amorphous chains in the starch granule as a result of intermolecular bridges. However, Jyothi et al (2006) showed that cross-linked starch has more pronounced synaeresis than native starch because of ordered structure in the starch paste, thus resulting in a higher degree of retrogradation.…”

Physicochemical properties, modifications and applications of starches from different botanical sources

“…Depending on the reagent used for crosslinking, the final product is classified in one of three types: i) monostarch phosphate produced by starch esterification with orthophosphoric acid, potassium or sodium orthophosphoric or STPP; ii) distarch phosphate produced when native starch reacts with STMP or PDCl 3 ; or iii) phosphated distarch phosphate, resulting from combined treatments of monostarch and distarch phosphates (Gunaratne & Corke, 2007;Jyothi et al, 2006).…”