Physical properties and cooking quality of extruded restructured rice: impact of water temperature and water level

Abstract

Rice is the main food for approximately 3.5 billion people worldwide, especially in Asians, who have consumed more than 90% of the total rice produced. Restructured rice is another designation of artificial rice is an effort to diversify staple foods processed from carbohydrate-based raw materials with the addition of certain substances to improve the quality of staple foods. Restructured rice can be done with several techniques, such as using extrusion. This study aimed to investigate the effect water content (35%, 37.5%, 40%, 42.5%, and 45%) and temperature (100oC and 26oC) on the surface and characteristics of restructured rice using a pasta extruder. Results of this study showed the treatment with water content 40% and temperature 100oC to be the best, more precisely seen from the results of laser microscope, color, WAI, WSI, WAR, Cooking losses, and cooking time. Pores and surfaces of restructured rice are almost the same as milled rice. Water absorption index (WAI) value = 2.273±0.10 g/g, WSI = 2.114±0.11%, WAR = 150.99±0.77%, CL = 1.92±0.10% and cooking time 4 mins. Suggestions for this research are further studies such as fortification with other ingredients using a pasta extruder technology and are expected to be implemented and commercialized.