Effects of Debranching on the Formation of Maize Starch–Lauric Acid−β-Lactoglobulin Complexes

In this study, the effects of debranching on the structure and properties of the starch–lauric acid (LA)−β-lactoglobulin (βLG) complex were studied. Gel permeation chromatography and high-performance anion-exchange chromatography showed that debranching of amylopectin generated short linear chains, which increased in proportions with debranching time. Analyses from differential scanning calorimetry, laser confocal micro-Raman spectroscopy, and X-ray diffraction showed that debranching promoted the formation of starch–LA and starch–LA−βLG complexes, as characterized by the increased enthalpy changes and crystallinity and decreased full width at half maximum of the band at 480 cm–1. Debranching treatment for 6 and 18 h promoted complexation between starch and LA, while extensive debranching was unfavorable for the formation of starch–LA complexes. Similar results were also observed for the starch–LA−βLG complexes. Starch–LA−βLG complexes had more type II and less type I crystallites than starch–LA complexes. From this study, we conclude that debranching of starch favors the formation of starch–LA and starch–LA−βLG complexes, with more type II crystallites formed in starch–LA−βLG complexes.