Comparison of important quality components of red-flesh kiwifruit (Actinidia chinensis) in different locations

Important quality components of red-fleshed kiwifruit which was grown in three different regions in North of Iran were investigated in this research. Fruits produced in the region with higher altitude and cool summer temperatures showed higher ascorbic acid content (AAC), total phenolic content, and antioxidant activity than the two other regions both at harvest time and storage. It was observed that the 1,1-diphenyl-2-picrylhydrazyl was positively correlated with the AAC (r = 0.98), total phenolic content (r = 0.94), and the ferric reducing antioxidant power was positively correlated with the AAC (r = 0.98), TPC (r = 0.93). Fruits harvested in region 2 with cool environments, presented dark red flesh color with the highest values of anthocyanin content at harvest (2.78 mg CGE/100 g), with a gradually increasing trend during storage to reach 3.47 mg CGE/100 g at the end of storage. Total anthocyanin content correlated positively with soluble solids content (SSC; r = 0.82), total Soluble sugars (TSS; r = 0.94), pH (r = 0.94), SSC/titratable acidity (TA; r = 0.83) and negatively with TA (r = -0.77). Fruits grown in region 2 received the highest SCC and TSS scores after sensory test evaluations made by the panelists. During storage fruits firmness and total acidity of kiwifruit decreased while SSC, TSS, and anthocyanin content increased. Additionally, antioxidant compounds and taste-related quality of kiwifruit had a positive relationship with the product region. Results showed that the growing region and storage duration considerably influenced the antioxidant compounds and nutritional quality of red flesh kiwifruit.