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Starch‐lipid interactions of five maize starches varying in amylose content and chemical modification were investigated by differential scanning calorimetry (DSC). The high‐amylose maize starch gave the greatest endotherm due to the amylose‐lipid complex in presence of cetyltrimethylammonium bromide (CTAB). This endotherm was decreased in an acetylated high‐amylose maize starch, and the waxy varieties did not give rise to such an endotherm. However, when the gelatinization enthalpies were compared it was found that these values decreased also for waxy varieties in the presence of CTAB. Dynamic rheological measurements showed that CTAB increased the storage modulus (G′) for all the starches investigated (normal maize starch, acetylated high‐amylose maize starch and crosslinked waxy maize starch), whereas saturated monoglycerides increased G′ for normal maize starch, decreased G′ for the crosslinked waxy maize starch and left acetylated high‐amylose maize starch unaffected. Lecithin and soybean oil either decreased G′ or had no effect.

The retrogradation of waxy maize starch in the presence of surfactants and emulsifiers was measured by differential scanning calorimetry. I t was found that a surfactant (cetyltrimethylammonium bromide) and unsaturated monoglycerides reduced retrogradation, whereas lecithin and a soya bean oil influenced the retrogradation to a lesser extent. The effects were greater after 1 day of storage than after 7 days, and the influence of the sur$actant was greater at +25"C than at + 7°C. Different storage temperatures led to crystallised forms of amylopectin with different melting temperatures. Further, an amylopectin sample was affected by the presence of a surfactant in a way similar to the waxy maize starch.

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