Influence of the addition of fruit on the mineral content of yoghurts: nutritional assessment

The contents of copper, iron, zinc, manganese, calcium, magnesium, sodium and potassium were investigated in fruit-added yoghurts of seven different flavours, belonging to three commercial brands widely distributed on the international market. The analytical determinations were made by flame atomic absorption spectroscopy. The analyses of variance between flavours established statistically significant differences (P<0.05) for all the minerals analyzed. Differences in the mineral content were observed with the presence of different fruit, and there were notably high concentrations of iron and manganese in the wild berry fruit and pineapple flavours. Conversely, the peach-flavoured yoghurt had the lowest concentrations of iron, manganese, magnesium, sodium and potassium. In general, it was seen that the presence of fruit pieces in yoghurt caused an increase in the contents of copper, iron and manganese. Finally, their contribution to the daily intake was calculated from the mean concentrations of each of the elements investigated so that one yoghurt (125 g) gave a mean 28.1 μg of copper, 178 μg of iron, 390 μg of zinc, 8.5 μg of manganese, 123 mg of calcium, 11.7 mg of magnesium, 45.7 of sodium and 147 mg of potassium.