Effects of cationization on DSC thermal profiles, pasting and emulsifying properties of sago starch

Abstract

Cationic sago starches were prepared using an aqueous alkaline process with different levels of cationic reagent 3-chloro-2-hydroxypropyltrimethylammonium chloride (0.01-0.10 M), sodium hydroxide (0.03-0.86 M) and reaction temperature (30-62 • C). The degree of substitution (DS), reaction efficiency, thermal and pasting properties of cationic sago starches were analysed. Emulsifying and fat binding properties of native sago starch, cationized sago starch and commercial chitosan were compared at two different pH values (4 and 7). Degree of substitution increased with an increase in concentration of cationic reagent or NaOH, or reaction temperature. The reaction efficiency was proportional to the concentration of NaOH and reaction temperature but inversely proportional to the cationic reagent concentration. The highest DS and reaction efficiency achieved was 0.06 and 79%, respectively. The pasting temperature and gelatinization enthalpy of cationic starch (DS 0.06) were lower compared with native sago starch. Cationization increased the peak viscosity and breakdown of the starch paste but decreased the setback. The presence of cationic groups significantly increased emulsion stability, emulsion viscosity and fat binding capacity of sago starch. However, the cationic sago starch was still inferior to chitosan, which showed the highest emulsion stability, emulsion viscosity and fat binding capacity. There was no significant difference between the surface tension values of native and cationic sago starch and chitosan. The influence of pH on emulsifying properties was not significant. The emulsion stability of the cationic sago starch improved due to an increase in viscosity and fat binding capacity but not its surface active property.

Preparation and characterization of high degree substituted sago (Metroxylon sagu) starch with propylene oxide

“…This explains the higher clarity of HPSS at increasing degrees of substitution 28. Other substituted starches, such as cationic starch 29 and acetylated starch 23, also form clear pastes or gels.…”

The Structure and Characteristics of Sago Starch

“…Intrinsic viscosity decreased with increasing temperature, but the critical concentration remained fairly constant over the range of temperatures (Nurul et al 2001). Siau et al (2004) attempted to make cationic sago starch using 3-chloro-2-hydroxypropyltrimethylammonium chloride (0.01-0.10 mol L −1 ) and sodium hydroxide (0.03-0.86 mol L −1 ) and found that the gelatinization enthalpy of cationic sago starch was lower, compared with native sago starch. The enthalpy of a transition is explained as corresponding to the amount of crystal order (or double helical structure) in the starch suspension (Mohamed et al 2008).…”

Starch from the Sago (Metroxylon sagu) Palm Tree—Properties, Prospects, and Challenges as a New Industrial Source for Food and Other Uses

“…The potential of using sago starch as a biomass source has been explored by Wang and others (1996). To further enhance the utilization of sago starch, modifications such as cross‐linking and hydroxypropylation (Wattanachant and others 2003), phosphorylation (Muhammad and others 2000), succinoylation (Sun and Sun 2002), carboxymethylation (Noor Fadzlina and others 2005), cationization (Siau and others 2004), and enzyme modifications (Wong and others 2007) have been carried out on sago starch. These processes can alter the properties of sago starch such that it might find further applications in the food industries as thickener, stabilizer, and texturizer (Bujang and Ahmad 2000).…”