Pasting Characteristics and In Vitro and In Vivo Digestibility of Low-, Medium-, and High-Amylose Types of Mung Bean Flour after Heat-Moisture Treatment

Mung bean (Vigna radiata L.) flour varieties of varying amylose content are heat-moisture treated at 100 degrees C for 6 h, and changes in their pasting properties and digestibility are investigated. Amylose content of the low-amylose (LAM MB), medium-amylose (MAM MB), and high-amylose mung bean flour (HAM MB) is 16.1%, 23.2%, and 31.7%, respectively. Mung bean flour after heat-moisture treatment (HMT) shows significantly reduced peak and breakdown viscosities and swelling power compared to those in native flours. However, pasting temperature, final and setback viscosities, and solubility of the mung bean flour significantly increase after HMT. The treated mung bean flour also contains higher amounts of resistant starch (RS, 19.6%-30.6%) than that in the corresponding untreated flour (14.9%-17.5%). Consequently, mung bean flour subjected to HMT induces a lower blood glucose response in mice and exhibits lower glycemic index (GI) values than that of untreated flour. Among all mung flour types subjected to HMT, the HAM MB exhibits the highest viscosity, solubility, and swelling power and has the highest RS content (30.64%), and the lowest blood glucose response and GI value. Thus, mung bean flour after HMT with desirable properties and digestibility can be used in the production of low-carbohydrate foods. Mung bean flours varying amylose content are heat-moisture treated at 100celcius for 6h. The HMT forms the starch granules being more stable to continuous heating and agitation, lower swelling power and higher solubility and produces more RS content, resulting in lower blood glucose response and glycemic index. image