Influence of Storage Temperature on Shelf-life of Minimally Processed Cactus Pear Fruits

Cactus pear fruits (Opuntia ficus indica Mill, cultivar Gialla) were manually peeled, placed in polystyrene trays and packaged with a heat-shrinkable film, then kept at 4 °C and 15 °C for 11 d. After 4, 8 and 11 d chemical-physical, microbiological and sensorial parameters were determined, while in-package gas concentrations were measured daily. Chemical-physical and sensorial parameters did not show significant changes in 4 °C-stored fruits until d 8, while those kept at 15 °C experienced a dramatic increase in acidity, ethanol accumulation, strong off-flavour development and loss of overall fruit freshness and firmness. Microbiological growth rate was much higher at 15 °C than at 4 °C. Visible manifestation of moulds was detected on 4 °C-stored fruits on d 11, while in the 15 °C-stored fruit, fungi colonization had already started on the fourth day. Based on these results, we conclude that quality of peeled cactus pear fruits can be maintained at 4 °C for 8 d, while abuse of temperature (15 °C) limits shelf-life to 4 d. Copyright 2000 Academic Press