Impact of amylose content on structural changes and oil absorption of fried maize starches

The absorption of oil during frying has important implications for food quality, cost, and nutrition. Maize starches with low (WMS), intermediate (NMS), and high amylose (HAMS) contents were therefore heated in oil to mimic the frying process, and the impact of amylose content on the hierarchical structures and oil absorption of the fried starches was evaluated. Amylose affected the oil absorption by interfering with the structural evolution of the starch or by directly interacting with the lipids during frying. At low moisture level (20%), the granular state was preserved after frying and so the size and porosity of the granules played a dominant role in the oil absorption process, explaining why the highest oil absorption occurred in WMS. At 40% moisture content, NMS absorbed the most oil because of its granular morphology and lower crystallinity. At 60% moisture content, HAMS absorbed more oil than NMS, because more amylose molecules in HAMS provided more hydrophobic helical cavities available for lipids.