Influence of acidulants on bioaccessibility of zinc from green leafy vegetable products*

摘要

Zinc deficiency is known to affect a majority of the population worldwide. Green leafy vegetables are good sources of micronutrients and are a cost effective means to combat micronutrient deficiency. The bioavailability of minerals is very low from plant foods and organic acids are known to enhance their bioavailability. Organic acids are used in Indian culinary in different forms of preparations to enhance the flavor and taste. The present investigation was undertaken in Dharwad during 2009-10 to know the influence of commonly used acidulants viz., lime juice, tomato puree, tamarind and raw mango powder in two green leafy vegetable based food preparations viz., fenugreek bhaji and shepu dhalvada on the bioaccessibility of zinc. Bioaccessibility was studied by simulating gastro intestinal digestion and equilibrium dialysis in- vitro method. The study reveals that moisture (71.26 %) and ash content(7.40%) of fenugreek bhaji with tomato was highest. Lower acidic pH was recorded in tamarind added bhaji (5.51) and significantly highest pH (6.29) in tomato puree added bhaji. Shepu dhalvada with tomato puree had significantly higher moisture content (40.77%) and least was found in tamarind added dhalvada (36.01%). Ash content of dhalvada ranged from 4.06 to 4.61 per cent. Shepu dhalvada with the addition of lime juice recorded significantly lower pH of 5.03. The zinc content was 2.6 mg/100 g in fenugreek bhaji and 2.00 mg/100 g in shepu dhalvada. Bioaccessibility of zinc increased with the addition of all the acidulants in case of fenugreek bhaji from 47.30 per cent in control to 70.62 per cent in tomato added fenugreek bhaji and least in sample with lime juice (57.15%). While in the case of shepu dhalvada the zinc bioaccessibility decreased with addition of acidulants- lime, raw mango powder, tamarind and tomato from 65.00 per cent in control to 62.66, 57.65, 55.15 and 50.26 per cent respectively.