PIXE Elemental Analysis of White Soil Clarifier in Traditional Grape Syrup Production

The white soil is used as a clarifier, in the traditional preparation process of grape syrup, to reduce the acidity and deposit the suspended colloidal substances. Besides increasing the nutrients in grape syrup, the substances in white soil may also have side effects on the final product. In grape syrup production, heating the grape juice and soil mixture to the boiling point makes more soil absorption. Determining the chemical composition and the concentration of the used white soil is vital for producing a healthy product. In this study, white soil samples were collected from 10 areas commonly known as white soil excavation sources in Malayer City, Hamadan, Iran. The dry white soil samples were then prepared to be analyzed by the Proton-Induced X-ray Emission (PIXE) technique. Ca had the highest and Mg had the lowest value of concentration among the detected elements of Mg, Al, Si, S, K, Ca, Ti, Mn, and Fe in the collected samples. From the statistical analysis, it was revealed that the Ca content of the soil is significantly incompletely correlated with other detected elements. In addition, Ca, Si, and Al had a significant difference (p 0.001) with other identified elements. The higher amount of Mn and Fe makes the darker color of the syrup while the higher content of Ca increases the transparency of the syrup color. The grape syrup made from the soil containing the highest level of Ca was tasty, more transparent, and light brown in color.