Monitorization of mineral content and location after 3 months of storage of naturally enriched potato (Solanum tuberosum L.) with Calcium

Potato (Solanum tuberosum L.) is one of the most important staple food crops and one of the most consumed worldwide. As such, is a suitable food matrix for biofortification studies, namely with Ca, as it is an essential mineral for plant growth and development, being required for several structural issues. In this context, this study aimed to monitor the mineral content and location of Ca and other essential minerals (K, P, S, Fe, and Zn) and assess some quality parameters (color of the pulp, total soluble solid and dry weigh content) in tubers of Solanum tuberosum L. (Agria variety) after three months of storage, submitted to a Ca biofortification process with four foliar sprays with three concentrations of calcium nitrate (0.5, 2 and 4 kg.ha^-1) and two concentrations of calcium chloride (3 and 6 kg.ha^-1). It was found out that in most treatments, Ca, K, S, Fe, and Zn have higher content in the epidermis region and that control tubers showed a lower dry weight content compared to the biofortified ones. Moreover, after three months of storage, naturally enriched tubers maintain a preferential accumulation of Ca in the epidermis region (as seen in harvest) and showed a decrease in the dry weight content in control and biofortified tubers (compared to harvest data). Additionally, no significant differences were observed in the colorimetric parameters of pulp tubers and in the total soluble solid content, presenting similar data to the harvest ones. In conclusion, the storage process of biofortified tubers affected a quality parameter – dry weight content – being relevant for industrial processing and a criterion for potato tubers classification. In this context, only Ca(NO₃)₂ 2kg.ha^-1, CaCl₂ 3 and 6 kg.ha^-1 treatments presented suitable for industrial processing after 3 months under storage conditions.