Quality characteristics of honey enriched brown rice flour extrudates

Research was undertaken to investigate the effect of brown rice flour along with honey on physico-chemical properties of extrudates at varying processing conditions. Brown rice flour and honey at different proportion (1.59–18.41%) were blended and extruded by co-rotating twin screw extruder at varying extrusion conditions viz., feed moisture (14–18%) and barrel temperature (120–180°C) at constant screw speed (500 rpm). Effect of these independent factors on expansion ratio, bulk density (BD), water absorption index (WAI), water solubility index (WSI) and hardness as responses were studied. Central composite rotatable design was used to plan the experiments. Product responses were significantly (p<0.05) influenced by all the independent variables. Results indicated that expansion ratio was negatively affected by feed moisture, barrel temperature and honey proportion, whereas the bulk density and hardness were positively affected by these variables. Feed moisture had positive but barrel temperature and honey proportion had negative effect on water absorption index of extrudates. Consequence of feed moisture on water solubility index was negative, while that of barrel temperature and honey was positive. This study demonstrated the potential utilization of brown rice flour and honey in preparation of nutritionally high quality extruded products.