Effects of modified atmosphere packaging on the quality of minimally processed cauliflower

Abstract

In this study, cauliflower florets were treated with NaCl (1%) + Na-metabisulphite (1500 ppm) solution and chlorinated (150 ppm, pH: 6.9). They were then rinsed with tap water. In this manner, one group of vegetables was treated with citric acid solution (1.5%) and the other group with Ca-ascorbate (0.5%) + citric acid (1%) solution. After centrifugation, the samples were packed in 20% atmospheric air + 80% N-2 and 20% atmospheric air + 70% N-2 + 10% CO2 conditions with bi-axially oriented polypropylene (BOPP) film. After 15 days of storage at 4 +/- 2 degrees C ascorbic acid, total phenolics, and total carotenoids contents have decreased; whereas aerobic mesophilic, psychrophilic, total coliform bacteria counts and polyphenol oxidase activity have increased. The losses of ascorbic acid, total phenolics, total carotenoids, and antioxidant activity were determined as 11.54%, 7.56%, 29.08% and 17.36%, respectively. Generally, greater reductions occurred in blank samples which were not treated with any chemicals, but were packed under modified atmosphere conditions. A little weight loss, total dry matter loss, and polyphenol oxidase activity increase was found in samples packaged in carbon dioxide enriched atmosphere and treated with Ca-ascorbate + citric acid. This condition was also found to be more effective in limiting the quality losses and preventing organoleptic degradation. On the contrary, control samples were generally rejected by the panelists at the 95% probability level because of their deleterious odour and colour.