SWEETPOTATO-BASED FORMULATION AN ALTERNATIVE FOOD BLEND FOR COMPLEMENTARY FEEDING

Abstract

In an effort to reduce the prevalence of protein-energy malnutrition among older infants, cereal-legume blends are being promoted as suitable complementary foods instead of cereal-only porridges. An example of such blend is Weanimix, which is a blend of non-dehulled maize, groundnut and non-dehulled soybean/cowpea. Although Weanimix has adequate protein and energy densities, it contains a significant level of phytate (an antinutrient that reduces iron, zinc and calcium biovailability) and virtually no β-carotene (vitamin A precursor) when white maize is used for processing. Additionally, cereal-based infant foods form a very thick porridge that requires dilution with water to get the desirable viscosity, leading to ‘energy and nutrient thinning’ (i.e. reduction of energy and nutrient densities). This chapter summarizes the potential of an alternative complementary food formulated from sweetpotato (denoted as ComFa) using both household- and industrial-level processing methods. Both ComFa formulations (home-based and industrial-level) and Weanimix (prepared for comparison) met the stipulated energy and fat values specified in the Codex Standards. However, the protein content of the industrial ComFa formulations (extrusion-cooked ComFa and roller-dried ComFa) was lower by 17%, but the oven-toasted ComFa (household-level formulation) and Weanimix met the protein specification. The phytate content in all the ComFa formulations was approximately a quarter of the level of 0.80 g/100 g in the Weanimix. Only the sweetpotato-based infant foods contained measurable levels of β-carotene, resulting in significantly higher vitamin A content of the oven-toasted ComFa compared with enriched Weanimix (28.73 versus 1.20 μg retinol equivalents/100 kcal). On average, sweetpotato-based formulations were higher in maltose (26 times), sucrose (five times), free glucose (19 times) and fructose (seven times) than levels in enriched Weanimix, but the ComFa formulations contained significantly less starch (10–13 versus 47 g/100 g). The high simple sugar and low starch levels in the ComFa formulations could explain the lower apparent viscosity (nine-, 13- and 20-times, for peak, ‘consume’ and final viscosities, respectively), higher water solubility index (seven times), and higher consumer acceptance compared with the maize-based formulation. On the basis of the compositional, functional and sensory findings of this study, the sweetpotato-based formulations have significant advantages as a complementary food compared with Weanimix due to the low level of phytate, the high levels of endogenous β-carotene and low viscosity