Sensory evaluation of fortified rice flour based foods at different levels of fortification

Abstract

In order to determine the effects on the physical and sensory characteristics of rice flow preparations after fortification with different levels of iron and zinc a study was carried out to ascertain which level of fortification would be most appropriate in Sri Lanka. The mineral forms tested were ferrous sulfate, zinc oxide, folic acid and Di-sodium EDTA. Iron and zinc were added to rice flour to provide 60, 80 and lOOmg per kilogram of flour. Folic acid was added to provide 2mg per kilogram of flour. Na2EDTA was mixed at a molar ratio of 1:1 of Fe: Na2EDTA and 1:0.7 of zinc: Na2EDTA in a tumble laboratory blender. The flour was stored at ambient conditions (3(f-40°C, relative humidity nearly 80.0%) at the Nutrition Research Laboratory (NRL) of the Faculty of Medicine, Galle. At monthly intervals, three dishes, viz., string hoppers, pittu and aluwa, that were prepared out of enriched flour were evaluated for their sensory characteristics, using 13 trained and experienced panelists. Meals were prepared at the NRL. The sensory changes of all foods over the unfortified food remained positive and, most of the changes were related to flour storage time and to the level of the fortificant. A significant difference in acceptability of pittu over aluwa (p=0.028) was observed in all stages of the trial. Odour of meals made out of flour at 80 mg/kg level were significantly different from that of meals of 60 mg/kg (p=0.046). Odour of meals at second month were significant from meals at the end of first month (p=0.004). Taste of meals made out of 80 mg/kg was shown to be more acceptable to the panelists from 60 mg/kg (p=0.019) and 100 mg/kg (p=0.001). There was no significant difference in taste between type of meals (p=0.991) and duration of storage (p =0.735). Fortificant level of 80mg/kg for iron and zinc appeared viable