ENZYME-RESISTANT STARCH .4. EFFECTS OF COMPLEXING LIPIDS

Amylomaize VII starch, autoclaved at 125-degrees-C, was reacted during cooling below 100-degrees-C with lysophosphatidyl choline (LPC), sodium stearoyl lactylate (SSL), and hydroxylated lecithin (OHL). Differential scanning calorimetry (DSC) peaks at around 95-110-degrees-C indicated formation of lamylose-lipid complexes and at around 155-degrees-C indicated the presence of enzyme-resistanc starch (RS). Yields of RS from complexed samples isolated by thermostable bacterial alpha-amylase or amyloglucosidase were lower than yields of RS from the autoclaved and cooled control. Formation of complexes competes with amylose chains involved in generation of RS. Amylose-lipid complexes are enzyme-degradable, and an increase in complexed amylose reduced yields of RS. Amylose recrystallization in RS formation is competitively affected by complexation of amylose with LPC and SSL. Results of X-ray diffraction powder crystallography were in agreement with DSC measurements. Complexes of amylose with LPC, SSL, and OHL gave rise to V-type patterns; enzymatic hydrolysis of the complexes yielded B-type RS structures.