Effect of processing methods and blending cereal and legume grain on some mineral and sensory qualities of weaning foods

Abstract

The most important nutritional problems in weaning foods consumed by infants in many parts of developing nations including Ethiopia are deficiencies in macronutrients and micronutrients. In view of this, the effect of processing method and blending of teff, finger millet, and sprouted groundnut on mineral contents and sensory acceptability of weaning food gruel was investigated. The treatments consisted of three blends B₁ (20% teff + 40% finger millet + 40% groundnut), B₂ (30% teff + 30% finger millet + 40% groundnut) and B₃ (40% teff + 20% finger millet + 40% groundnut) and six processing condition (roasting, fermentation, three duration of sprouting and unprocessed blend as a control). The experiment was laid out as a Completely Randomized Design (RCD) in a factorial arrangement (3 x 6 = 18 treatments) and replicated three times per treatment. The mineral contents of initial ingredients and blended samples were analyzed using standard methods. Processing condition had significant (P < 0.05) effect on mineral and sensory properties of weaning food gruel. On sprouting (groundnut), roasting, and fermentation, zinc content increased. The highest zinc content (3.86 mg/100 g) was obtained in response to sprouting groundnut for 12 hr in blend B₃ and the lowest was (1.91 mg/100 g) in the control weaning food B₁. The highest iron (32.96 mg/100 g) content was recorded for roasted weaning food of B3, while the lowest (14.70 mg/100 g) was obtained in the control blend B1. The highest calcium (304.82 mg/100 g) content was in the roasted weaning food blend B₁ and the lowest (110.63 mg/100 g) was in the control blend B1. Sensory analysis revealed that the most acceptable product was obtained from roasted blends of weaning food (i.e., color, flavor, taste and overall acceptability scores of 5.36, 5.66, 5.84 and 5.75 on 7-point hedonic scale, respectively). Overall, the result showed, roasting or fermentation or sprouting of groundnut (12 to 24 hr and drying the sprout at 50^oC for 20 hr) and blending level at B₃ have improved the nutrient quality and sensory acceptability of weaning food gruel compared to control sample. In the developing country like Ethiopia factory processed weaning foods are not affordable for majority of the population, such domestic processing conditions can be promoted at each household to improve weaning food gruel quality for child of weaning age.

Keywords: Blending ratio; fermentation; finger millet; groundnut sprouting; teff, mineral contents; roasting, sensory quality