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 degreesC and 15 degreesC for 11 d. After 4, 8 and II d chemical-physical, microbiological and sensorial parameters were determined while in-package gels concentrations were measured daily. Chemical-physical and sensorial-parameters did not show significant changes in 4 degreesC-stored fruits until d 8, while those kept at 15 degreesC experienced a dramatic increase in acidity ethanol at accumulation, strong off-flavour development and loss of overall fruit freshness and firmness. Microbiological growth rate was much higher at 15 degreesC than at 4 degreesC. Visible manifestation of nzoulds was detected on 4 degreesC-stored fruits on d 11, while in the 15 degreesC-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 degreesC for 8 d while abuse of temperature (15 degreesC) limits shelf-life to 4 d.