Postharvest physiology and storage potential of new Chilean raspberry cultivars

Carolina Contreras1, Adolfo Hermosilla2, Élida Contreras2, Paulina Naranjo2, Juan Pablo Zoffoli2, and Marina Gambardella2*
Raspberries (Rubus ideaus L.) are highly perishable and susceptible to rot during storage. An exploratory study of postharvest physiology associated with maturity was carried out for three new Chilean raspberry cultivars: Santa Catalina, Santa Clara and Santa Teresa. Fruit of these cultivars were harvested at three maturity stages based on color: pink (C3), bright red (commercial maturity) (C4) and dark red (C5). Two experiments were carried out to: i) determine postharvest quality and physiological parameters associated with maturity stages in comparison to those fruits of the main cv. Heritage, and ii) evaluate storage potential at 0 and 4 °C of ‘Santa Catalina’. In the first study, fruit quality parameters (such as weight, firmness, color, among others) of all the ‘Santa’ cultivars were assessed immediately after harvest, and the ethylene production and respiration rates (CO2) were recorded for 4 d at 20 °C. In the second experiment, ‘Santa Catalina’ was stored at 0 and 4 °C. According to the results of the first experiment, ‘Santa Teresa’ presented the largest fruit (7.9 g), followed by ‘Santa Clara’ (5.3 g), ‘Santa Catalina’ (4.9 g) and ‘Heritage’ (3.3 g). ‘Santa Clara’ (~ 6 ng kg-1 s-1) fruits had the highest levels of ethylene production, followed by ‘Santa Catalina’, and ‘Santa Teresa’ with the lowest production. Regardless the cultivar, the fruit at the C5 stage always showed the highest ethylene production. Overall, compared with ‘Heritage’, these three new cultivars presented better fruit quality at harvest. The 0 °C was an adequate storage temperature for ‘Santa Catalina’ reaching storage potential of 20 d without soft fruits; therefore, it is recommended for fresh markets.
Keywords: Ethylene production, quality, respiration rate, Rubus ideaus, storage potential.
1Universidad Austral de Chile, Facultad de Ciencias Agrarias y Alimentarias, Instituto de Producción y Sanidad Vegetal, Isla Teja S/N, Valdivia, Chile.
2Pontificia Universidad Católica de Chile, Facultad de Agronomía e Ingeniería Forestal, Vicuña Mackenna 4860, PO Box 7820436, Santiago, Chile. *Corresponding author (mgambardella@uc.cl).