Investigating internal browning in ‘Cripps Pink’: preharvest climate, ripening rate, canopy position and dynamic controlled atmosphere storage

Fuente: ISHS (International Society for Horticultural Science)
Post date: Wednesday 3 September 2025
Author:
ISHS Secretariat

Daniela Ramos is an MSc(Agric) student at the Department of Horticultural Science, Stellenbosch University, South Africa, under the supervision of Dr. Elke Crouch. Her research focuses on assessing pre- and postharvest factors influencing internal browning development in ‘Cripps Pink’ apples. She is collaborating on this project with Dr. Mariana Jooste from HortgroScience as well as Heleen Tayler and Dr. Ian Crouch from ExperiCo (AgriResearch Solutions). Her study investigates the connection between climate-driven physiological fruit development and the effect of canopy position on the postharvest storage performance and maturity of ‘Cripps Pink’ apples. Climate and orchard data have been collected across 90 orchards and four seasons (2021/2022 - 2024/2025). Maturity indexing data was collected four to six weeks before the optimum harvest date. After harvest, fruit were stored for 9 months in CA storage (1.5 kPa O2; 0.5 kPa CO2) at -0.5°C followed by six weeks regular atmosphere storage (RA) at -0.5°C and a simulated 7-day shelf-life at 20°C. Thereafter fruit quality was assessed. The results of the study have shown that inside canopy fruit generally had a higher incidence of internal browning irrespective of the maturity at harvest after long-term storage. To minimise the incidence of internal browning and postharvest losses, Daniela is also studying dynamic controlled atmosphere chlorophyll fluorescence (DCA-CF) as an alternative to controlled atmosphere (CA) storage. These storage methods were compared across three seasons (2021/2022 - 2023/2024) and multiple farms to determine if DCA-CF (O2 ≈0.4 kPa; CO2 <0.5 kPa) was able to retain fruit quality better than CA storage (1.5 kPa O2; 0.5 kPa CO2). Initial results demonstrate that post-optimum harvested fruit should not be stored under low oxygen for extended storage periods. However, storing fruit under DCA-CF generally resulted in a reduced incidence of internal browning and better retention of specific fruit quality parameters.
Daniela Ramos won the ISHS Young Minds Award for the best oral presentation at the XIV International Controlled and Modified Atmosphere Research Conference in USA in May 2025.
Daniela Ramos, Department of Horticultural Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa, e-mail: daniela8888ramos@gmail.com
The article is available in Chronica HorticulturaeTags: Cripps Pink applesCategories: Young Minds Award Winners