Argon and high content of CO₂: The future for fresh-cut apples packaged in MAP

The growing interest in recovering a healthy lifestyle based on fresh and healthy diet has led to the emergence of minimally processed or "ready to eat" products. Minimally processed products are more perishable than the fresh whole original product, because the processing operations (wash, peeled, cut, etc.) increase their respiration rate; therefore the rate of degradation also increases. Currently, refrigeration storage and Modified Atmosphere Packaging (MAP) are the main technologies to prolong the shelf-life of minimally processed products. However, the food industry is constantly researching new applications to extend its shelf-life beyond 7 days. The objective of this study was to assess the effects of modified atmosphere containing high levels of carbon dioxide or argon, on the shelf-life of minimally processed apples compared to regular gas mixtures employed to preserve these kinds of products. Three different gas mixtures were studied 5% O₂, 5% CO₂, 90% Ar; 5% O₂, 35% CO₂, 60% N2, and 5% O₂, 5% CO₂, 90%N2. During 14 days a range of quality indexes were evaluated in fresh-cut apples: headspace, color, pH, texture, weight loss and microbial spoilage. The main results showed that apples packaged with Ar-containing mixture presented an increase of the browning index at the end of the storage time, compared with the other treatments. However, mixtures with argon and high carbon dioxide showed an inhibitor effect against mold growth.