Effects of monoglycerides on pasting properties of wheat starch after repeated heating and cooling

The effects of repeated heating and cooling on the properties of pastes prepared from a commercial wheat starch (Triticum aestivum L.) with added monoglycerides were studied using a Rapid Visco Analyser (RVA). The nanostructure of the freeze-dried pastes was determined by X-ray diffraction and small-angle X-ray scattering. Pastes prepared from the wheat starch alone, or from the starch mixed with tripalmitin, which does not form complexes with starch, produced regular viscosity profiles in the RVA when subjected to multiple heat-cool cycles. In comparison, the effects of adding monoglycerides (or monoacylglycerols) depended on the chain length and saturation of the fatty acid of the monoglyceride. Repeated heat-cool cycles in the RVA of the starch with different monoglycerides induced the formation of complexes of varying stability that influenced the viscosity trace of the paste during multiple heating and cooling cycles. Small-angle X-ray scattering in combination with X-ray diffraction proved useful in describing the nanostructural changes in the RVA pastes induced by monoglycerides and temperature cycling. The results indicate that the functional properties of starch pastes may be manipulated through the strategic selection of an added monoglyceride.

► Wheat starch pastes were heated and cooled repeatedly with different monoglycerides.
► The monoglyceride used affected the stability and viscosity of the starch-lipid complexes.
► Starch paste properties can be manipulated using different monoglycerides and heat-cool cycles.