Crop load density affects ‘York’ apple juice and hard cider quality

Abstract

To assess the impact crop load has on hard cider chemistry, ‘York’ apple (Malus × domestica Borkh.) trees were hand thinned to three different crop loads: low [two apples per cm2 branch cross-sectional area (BCSA)], medium (four apples per BCSA), and high (six apples per BCSA). Higher crop loads produced smaller, less acidic fruit that were slightly more mature. In juice made from fruit from these treatments, the total polyphenol content did not differ at harvest, but, after fermentation, the medium crop load had 27% and the high crop load had 37%greater total polyphenol content than the low crop load. Yeast assimilable nitrogen (YAN) concentration in juice made from fruit from the low crop load treatment had 18%and 22% greater than the medium and high crop load, respectively. YAN concentrations in juice from the medium and high crop load treatments were similar. Our results provide apple growers and hard cider producers with a better understanding of how apple crop load impacts YAN concentrations in juice and total polyphenol concentrations in juice and cider.