Effects of Various Surfactants on Rheological Properties of Maize Starch Granules

Abstract

In this study, the formation of complexes between surfactants and the helical chains of amylopectins was confirmed. Nonionic surfactants with hydrophobic and hydrophilic groups of appropriate size and chemical structure enhanced the swelling and gelatinization processes of starch granules. Hydrophobic groups form complexes with the amylose and linear chains of amylopectin by becoming inserted into the hydrophobic inner area of the helical structures. The hydrophilic groups help the approach of the hydrophobic groups into the hydrated molecular chains and thus aid the formation of the complex. Among the anionic surfactants tested, SDS and sodium n‐decyl benzenesulfate caused maximum swelling and gelatinization peaks. The average length of the amylopectin exterior chains is almost the same as that of the hydrophobic chains of SDS (16.9 Å) and of sodium decyl benzenesulfate (18.2 Å). This suggests that these anionic surfactants form rigid complexes with the exterior of the amylopectin by fitting their hydrophobic chains to the hydrophobic inside of the helical structures of these short exterior chains. This process was clarified by NMR analysis and by a decrease in the complex with the addition of iodine. The hydrophobic alkyl chains of anionic and cationic surfactants fix to the edge of the starch molecular chains by forming inclusion complexes with the helical chains of the amylopectin. Cationic ions interact with the starch molecular chains, causing a negative charge that results in a more rapid and efficient swelling of the starch granules. A decrease in setback value occurs due to the inhibition of rearrangement among the starch molecular chains. With SDS, the complex molecular chains become more extensively developed through the repulsion effects of the anionic ions resulting in a larger swelling power and gelatinization peak.

Effects of cross-linking and low molecular amylose on pasting characteristics of waxy corn starch

“…Cross-linked waxy corn starch showed a SDS-effect similar to that of normal corn starch. SDS forms a complex with helical molecular chains in amylopectin and increases the swelling of starch granule (Kurakake et al, 2004). In 10 h-cross-linking, each viscosity was smaller than that of the untreated starch, and onsets of gelatinization and peak temperatures increased.…”

“…The mixture causes rearrangement among the molecular chains within the starch granule as with heat-moisture treatment (Kurakake, Noguchi, Fujioka, & Komaki, 1997 Addition of the SDS (sodium dodecyl sulfate) surfactant during the pasting process is used to analyze the degree of interaction among molecular chains in starch (Kurakake, Noguchi, Fujioka, & Komaki, 2008). In normal corn starch, SDS improves the swelling of starch granules through the formation of complexes with starch molecular chains and negative-charge repulsion (Kurakake, Hagiwara, & Komaki, 2004). In cross-linking of waxy starch, the effect of SDS on the pasting properties was investigated.…”

Pasting Characteristics of Maize Starch Heat‐Treated with Different Water‐Ethanol Mixtures

“…SDS improves the swelling of starch granules through the formation of complexes with starch molecular chains and negative-charge repulsion (Kurakake et al 2004) and releases lipids from starch molecules due to the ability of the surfactant (Evans 1986). SDS improves the swelling of starch granules through the formation of complexes with starch molecular chains and negative-charge repulsion (Kurakake et al 2004) and releases lipids from starch molecules due to the ability of the surfactant (Evans 1986).…”

Effect of cellulose-derivatives and emulsifiers on creep-recovery and crumb properties of gluten-free bread prepared from sorghum and gelatinised cassava starch

“…The ability of emulsifiers to delay crumb firming is largely based on their hydrophilic-lipophilic index and potential for ionization (Armero & Collar, 1998;Gray & Bemiller, 2003;Stampfli & Nersten, 1995) which influence their interactions with proteins and intact starch granules or its constituent polymers. The hydrophobic groups of the emulsifier form complexes with amylose and linear chains of amylopectin and become inserted into the hydrophobic inner area of the helical structures whereas the hydrophilic groups facilitate the approach of the hydrophobic groups into the hydrated molecular chains and thus aid the formation of the complex (Kurakake, Hagiwara, & Komaki, 2004;Shiau, 2004). Interaction of the emulsifier with intact starch granules restricts granule swelling and disruption of its crystallinity during baking by complexing with amylose at the periphery of starch granules.…”