Development of Micronutrient Fortified Extruded Rice Analogues

Abstract

Fortified rice analogues can be manufactured using broken rice flour to suit the nutrient needs of target malnourished populations whose staple food is rice. The purpose of the study was to investigate the feasibility of fortifying rice analogues with iron and zinc. The fortificant mix was formulated to furnish 6.34 mg of iron and 2.10 mg of zinc per 100 g of broken rice flour. Iron fortificant used as micronised ferric pyrophosphate (MFPP) and zinc fortificant as zinc oxide (ZNO). Fortified extruded rice analogues were developed by extrusion technology. The physical properties of the fortified rice analogues were analysed. The length and weight of the fortified extruded rice analogues were 6.0 to 6.1mm and 0.034 to 0.035 g. The bulk density was ranged from 0.90 to 0.96 g/ml. The water absorption index was ranged from 2.31 to 2.33g/g and soluble loss was found to be 0.13 to 0.14 g/g. The physical properties of the rice analogues was found to be non significant (p<0.05) between the treatments (p<0.05). Colour measurement revealed that rice analogues fortified with MFPP had significant (p<0.05) colour differences, compared to analogues fortified with ZNO. However, MFPP, when combined with ZNO, had produced visual appearance closest to the unfortified rice analogue. The iron and zinc content of the unfortified broken rice flour (before extrusion) was 0.80 mg and 1.35 mg/100g. The iron and zinc content of the corresponding fortified rice analogues (after extrusion) were 7.13 mg and 3.35 mg/100g thus recording an iron and zinc retention of 99.85 and 99.70% respectively hence no significant difference (p<0.05) was found between fortified rice flour and fortified rice analogues. Sensory analysis revealed, no significant difference (p<0.05) for aroma, moistness, stickiness and texture, while the significant difference for appearance, firmness and overall acceptance. The study revealed that the rice analogues fortified with MFPP and ZNO could be used in food fortification programs and also could serve as a micronutrient enriched food to target malnourished populations whose staple food is rice.