Development and characterization of an analogue of rice by warm-extrusion of cañihua (Chenopodium pallidicaule Aellen) and rice (Oryza sativa) flours

Abstract

Many countries have native crops with excellent protein quality that are not widely consumed because they have been displaced by introduced crops such as rice. This work proposes the design of food matrices combining the structural and physical qualities of rice with high cañihua protein quality, a South America highlands ancestral crop. Different extruded cañihua-rice mixtures were physically and microstructurally characterized and compared with those of brown and extruded-rice. Cañihua-rice grains were treated by warm-extrusion process to give formulations of 10%?90% and 20%?80% of cañihua flour and rice flour, respectively. Physicochemical analyses showed that protein contents resulting from addition of cañihua-rice grains were 8.8% and 10%, respectively, compared to 7% of rice flour. Hardness of cooked cañihua-rice grains was similar to extruded-rice and slightly lower than cooked brown rice, while color of these grains was between those of extruded and brown rice. Microstructural analyses (FESEM and micro-CT) showed that extruded cañihua-rice mixtures had heterogeneous particles of cañihua flour embedded in rice flour structure. Sensorial analysis showed that cooked cañihua-rice from Cupi10 were similar to brown rice cooked. Finally, extruded cañihua-rice mixtures constituted a novel food matrix that could be used to increase the nutritional levels for consumers of rice.