No abstract

This study evaluated unripe fruits of ten apple cultivars removed during fruit thinning for their antioxidant activity and mineral content. The unripe fruits were collected from Chuncheon and Jeongseon located at Gangwon-Do of Korea. Antioxidant activities such as total phenolic content (TPC), total flavonoid content (TFC), DPPH (2,2-diphenyl-1-picrylhydrazyl) activity, FRAP (Ferric reducing antioxidant power), vitamin C and mineral contents were measured. In the unripe fruits obtained from Chuncheon and Jeongseon, TPC was in the range 8.97–81.4 and 7.11–42.15 mg GAE/g, TFC was in the range 9.38–33.81 and 6.83–19.24 mg QE/g, DPPH was in the range 27.17–82.58 and 29.73–73.24, FRAP was in the range 33.54–371.12 and 26.76–185.69 µM trolox /g, and Vitamin C was in the range 1.1–4.9 and 1.1–2.8 mg/AA/g, respectively. Among the cultivars tested, ‘Hongro’ and ‘Honggeum’ had consistently highest antioxidant activity, while ‘Summer King,’ ‘Tsugaru,’ and ‘Arisoo’ had the lowest value. ‘Picnic’ had the highest mineral contents expect P and K in Joengsoen, while ‘Summer King’ and ‘Tsugaru’ had the lowest value in both locations. These differences could be due to the genetic characteristics and/or their growth environments. These results could provide information to help with better utilization of thinned unripe fruits of apples in Korea.

No abstract

Climate change has had a significant impact on apple phenology and fruit quality worldwide. Similarly, a decline in fruit quality has been observed in major apple-producing areas of Korea. It is predicted that the ideal cultivation areas for apples would need to shift toward higher latitudes due to these changes. Hence, the objective of this study was to assess the influence of climate change on apple cultivated in a higher-latitude region. To achieve this goal, we investigated the flowering and harvest times of apples. Additionally, we measured fruit weight, soluble solid content, and titratable acidity over a period of 20 years in a higher-latitude region in Korea. Subsequently, we examined the relationship between temperature, phenology, and fruit quality through the use of linear regression and correlation analysis methods. The 20-year meteorological data revealed a consistent rise in temperatures. Consistent with this trend, we found a significant advancement in budbreak and flowering dates for the two major apple cultivars grown in a higher latitude in Korea. Furthermore, the increase in temperatures has positively influenced fruit quality, indicating that climate change has an impact not only on phenology, but also on the quality of apples in Korea. Considering the projected gradual increase in temperature, our findings strongly support that higher-latitude regions in Korea have the potential to become optimal locations for apple cultivation.