Functional Properties of Slow Carbohydrate Digestible Rice Produced Adapting Hydrothermal Treatment

Abstract

Functional properties of rice with slow carbohydrate digestibility developed by CFTRI (Mysore, India) were studied. The processed rice exhibited typical characteristics of pre-gelatinized starch, having high hydration at lower temperature (≤50°C) and low hydration capacity at higher temperatures (≥50°C). The insoluble amylose content and sediment volume of processed rice increased by 18.9 and 37.3%, respectively, compared to its native counterpart. Gel consistency was higher by four times, whereas resistant starch content of processed rice was higher by 2.6 times compared to native rice. The in-vitro carbohydrate digestibility of processed rice after 30 min was lower by 16% than its native counterpart. The pasting characteristics indices determined in rapid visco-analyser and the endothermic energy determined in the differential scanning calorimetry were considerably lower as compared to the native rice. The scanning electron microscopic examination revealed the continuous rigid matrix whereas the X-ray diffractograms showed negligible crystallinity of starch, indicating the presence of gelatinized starch in the processed rice. This observation indicates its suitability as a staple to the population at the risk of diabetes and obesity.