Preparation and characterization of inclusion complexes between debranched maize starches and conjugated linoleic acid

Abstract

Normal and high amylose maize starches were enzymatically debranched at different degrees, and then used for the preparation of inclusion complexes with conjugated linoleic acid (CLA). The recovery yield of CLA, percent ratio of CLA in the complexes to its initial amount, was increased by debranching, reaching 65% with a debranched high amylose starch (24 h). High amylose starch was more effective in the formation of CLA complexes with greater stability and crystallinity than normal starch. Both V6I and II crystals were formed by the complexation with CLA, and more V6II crystal was formed as the debranching and complexation times increased. However, an excessive complexation reaction for 24 h at 90 degrees C resulted in decreasing the CLA recovery, especially when normal maize starch was used. X-ray diffraction analysis revealed that B type crystals induced by starch recrystallization were also present during the complex formation. The enzymatic debranching facilitated the formation of crystalline complexes with CLA having a high thermal stability. The enzymatic debranching of starch enhanced the formation of crystalline complexes with CLA and availability of linear starch chains to form the complexes with CLA.