Quality of potatoes grown in various regions of Serbia as influenced by heavy metal and pesticide residues concentrations

It is possible to decompose starch into monosaccharides by the method of acid starch hydrolysis. By applying appropriate chemical procedure, a main solution is obtained, from which aliquots are taken after filtration to determine of the present glucose according to Luff-Shoorlu method. The analysed potatoes of cv. Desiree, grown on various sites in Serbia, have starch content that corresponds to available literature data. The highest starch content is found in potatoes from Ivanjica and Novi Pazar, i.e. from the areas where climate factors, air temperature, and land relief are favourable for potato growing. Lower starch contents are found in potatoes grown in flat areas with warmer climate and drier periods. Those are sites in PKB-Belgrade, Smederevo, Dobanovci and Mrčajevci areas, where the values obtained by experimental procedure are very similar. The lowest starch content is found in potatoes from Belegiš and Guča sites, where starch content is lower than normal from literature values, which may be explained by some special causes (climate, location, irrigation). On the basis of heavy metal contents in potato samples, it may be concluded that potatoes originating from sites famous for potato production are contaminated with Cd the content of which exceeds concentrations permitted by regulations. The presence of Cd in potato samples may also be explained by the application of phosphate fertilizers in higher (or recommended) rates. However, the soil itself should also be investigated, especially concerning the content of Cd and pH value. Thus, the influence of the soil itself should be established compared to fertilizer application in the current season. Presence of Cd in potatoes, on the other hand, is highly unfavourable because it prevents its utilization in nutrition, but also as a raw material for further processing of products based on potatoes: chips, etc. Also, Cd presence in foods is strictly controlled by EU, which prevents possible export of products based on potatoes containing Cd. Analyses of lindane and bensultap (Bancol) pesticides indicate that they are not within critical values, nor in such quantities to affect human health, so, from this aspect, the analysed potato samples from all sites are absolutely suitable for consumation.