Heat‐moisture treatment of oat grains and its effects on lipase activity and starch properties

The aim of this study was to evaluate the effects of the time of heat‐moisture treatment (HMT) of oat grains in husk on lipase activity, pasting properties of flour, and properties of starch isolated from grains. Oat grains with 13% moisture were subjected to 15, 30, 45, and 60 min of HMT at 110°C. Starches of heat‐moisture‐treated oat grains were isolated with the alkaline method. The 60‐min HMT suppressed more than 60% of the lipase activity of oat grains and increased the extraction yield of oat starch. HMT also reduced swelling power, solubility, gelatinisation enthalpy, and relative crystallinity of starches isolated from oat grains. The reduction of breakdown and retrogradation of oat flour promoted by 60 min of HMT provides better paste stability, and thus can be used for canned and frozen foods.