Pepino Dulce (Solanum muricatum Ait.) in Chile: Postharvest Storage Potential

Pepino dulce (Solanum muricatum Ait.), native species from The Andes area of Peru and Chile, is widely distributed in South America. It has been commercially and experimentally grown in several countries among them Chile, Peru, Colombia, USA, Israel, New Zealand, Australia and Spain. Among approximately 1,500 species described in the Solanum genus, pepino is one of the few domesticated and cultivated for food purposes. Pepino has been described as a succulent, juicy and sweet fruit mainly for dessert with excellent flavor. In Chile studies about pepino dulce are scarce, and some reasons may lie in the fact that pepino is classified as a secondary and exotic fruit, with a reduced product availability due to low cultivated area, and to minimum economic importance compared to other mayor crops such as table grape, apple, etc. All these problems have delayed the innovation and technology for this crop in Chile. Previous studies of pepino postharvest physiology have determined this fruit species to be chilling sensitive to temperatures lower than 5ºC and to physiological problems such as woolliness and internal browning. Potential storage time still remains unclear, and being highly dependent on fruit maturity. In regards to the climacteric behavior, pepino is not free of controversy since it has been described as climacteric and non-climacteric fruit. The aim of this study was to elucidate the physiological behavior of pepino dulce, and to study its storage potential. Five different harvest times were studied, fruits were collected from Ovalle (IV Region) north of Chile. Pepino fruits were stored at 20ºC and 7ºC and analyzed for respiration rate, internal ethylene production, and quality parameters (color, size, firmness, soluble solids, acidity, etc.) each harvest time. A sixth harvest was collected and stored under different postharvest conditions such as regular atmosphere, controlled-atmosphere and ethylene inhibitor (1-MCP) and evaluated after 10, 20, 30 and 40 days at 7ºC. Pepino fruit showed a climacteric pattern but very low respiration rate and ethylene levels, 12mL CO₂/k^-1.h^-1 and 0.1µLC₂H₄/ k^-1.h^-1, respectively. The effects of storage conditions will be discussed.