Effect of temperature on shelf-life and microbial population of lightly processed cactus pear fruits

The possibility of using cactus pear fruit (Opuntia ficus indica Mill, cv. Gialla) to produce ready-to-eat fruit was investigated. Changes in sensory quality and proliferation of spoilage microorganisms on lightly processed and packaged fruit as a function of storage temperature and modified atmosphere packaging were measured. The shelf life of the samples was kinetically modelled in order to check the effects of storage temperature and to assess the most relevant microbial indices for the product quality. Minimally processed cactus pear fruit had longer shelf life at 4◦C than at temperatures recommended for whole fruit when these were greater than 4◦C. The packaging of processed cactus pear fruit in modified atmospheres during storage resulted in a homogeneous bacterial population compared to that isolated from fruit stored in air, and favored the growth of Leuconostoc mesenteroides. Our results suggest that mathematical modelling might allow the industry to use more objective measurements to determine the shelf life of their products. © 2003 Elsevier B.V. All rights reserved