Peeling and cutting processes wound tissues and enhance deterioration in minimally processed fruits. Controlled atmosphere (CA) or modified atmosphere (MA) conditions can help maintain the quality of minimally processed products. The effects of various combinations Of CO2 and O-2 on the quality of fresh pineapple (cv. Smooth Cayenne) slices held at 4.5 degrees C were investigated. Among a range of CA treatments, 15 kPa CO2 maintained flesh colour, with low alcohol and acetaldehyde concentrations, and also prevented microbial growth. O-2 at 5 kPa also maintained a high visual quality, and gave low alcohol and acetaldehyde concentrations. Likewise, O-2 at 80 kPa maintained a high visual quality and prevented the accumulation of fermentation-related volatiles, but caused high electrolyte leakage. Both 5 kPa and 80 kPa O-2 treatments resulted in a reduced loss of firmness. Nonetheless, the respiration rate was higher in 80 kPa O-2 than in 5 kPa O-2. When the Optimum O-2 and CO2 concentrations were combined and compared to 21 kPa O-2 + 0 kPa CO2 (air control), both 5 kPa and 80 kPa O-2, with 15 kPa CO2, maintained the quality of pineapple slices. However, because low O-2 is more readily attained and maintained in MA, 5 kPa O-2 + 15 kPa CO2 appeared to be the most appropriate atmosphere for storage of minimally processed pineapple fruit.