Estimation of minerals in foods
The minerals in foods are determined by ashing or incineration at temperatures in the region of 500°C following standard procedure. This destroys the organic compounds and leaves the minerals behind. Ash thus obtained provides an estimate of the total mineral content of foods. Minerals in the ash are in the form of metal oxides, sulphates, phosphates, nitrates and halides. Individual minerals are determined by dissolving the ash, usually in acid, and measuring the mineral concentration in the resulting solution. Atomic absorption spectroscopy is generally used to estimate the mineral concentration. Nuclear Activation Analysis-NAA is a more sensitive method.