Preharvest factors that affect the development of internal browning in apples cv. Cripp’s Pink: Six-years compiled data

• A new category for internal browning in apples cv. Cripp’s Pink was detected in Chile.
• Logistic regressions for radial and mixed IB were stronger compared to diffuse IB.
• Radial IB was explained by GDH and firmness; diffuse IB, by GDH and background color.

Development of internal flesh browning (IB) of ‘Cripp’s Pink’ (Pink Lady™) apples was studied over 6 years (2004–2011), on stored fruit coming from different orchards. The aim was to determine the effect of geographical location, climatic condition and fruit maturity on incidence of IB in the most important production regions of Chile. Geographical and climatic conditions were based on latitude, longitude, altitude, growing-degree-days (GDD), growing-degree-hours (GDH) and days after full bloom (DAFB). Maturity indexes included flesh firmness, starch index, soluble solids, background and red skin color. Fruits were stored at 0–1 °C for 5 months and IB incidence evaluated after removal plus 7–10 days at 18 °C. The disorder was classified as radial, diffuse or mixed IB. Data were analyzed through ANOVA, principal components analysis (PCA) and logistic regression analysis. Results showed that radial and diffuse IB can appear within the same orchard, and both symptoms may be combined within a fruit (mixed IB), which has not been reported. The different ranges of diffuse, radial and mixed IB found after storage were highly influenced by preharvest conditions (geographic/climatic and maturity variables). Although the three types of IB were found to increase with extended harvests, which were associated with advanced maturity, relative strength of the models to predict IB were higher for radial and mixed IB (Max-rescaled R2 = 0.466 and 0.404, respectively), but less effective for diffuse IB (Max-rescaled R2 = 0.117). Data from 6 years suggest that radial IB could best be explained by GDH and firmness at harvest; diffuse IB could be accounted for by GDH and background color at harvest, whereas for mixed IB the most meaningful variables would be DAFB and background color.