Effects of ozone-enriched storage atmosphere on postharvest quality of black mulberry fruits (Morus nigra L.)

Ozone, a popular agent for food industry, was examined to extend the shelf life of fresh mulberry fruit. Changes in quality parameters of mulberries were investigated during storage in cold rooms with ambient air and ozone atmospheres (0.64 and 5.14 mg m−3) for 6 days at 2 °C and 95% RH. The selected quality parameters were the counts of total aerobic mesophilic bacteria (TAMB), Enterobacteriaceae, yeast-mold, weight loss, and the contents of ascorbic acid and total monomeric anthocyanins. On the first sampling day, the numbers of all microorganisms tested were significantly lower in the samples stored in 5.14 mg m−3 ozone atmosphere compared to that in air (p < 0.05). However, at the end of the storage period the counts of TAMB and yeast-mold in the samples stored in air and ozone were not significantly different (p > 0.05). The case was different for Enterobacteriaceae where the counts in the samples stored in 5.14 mg m−3 ozone atmosphere were significantly lower than the other samples (p < 0.05). Weight loss was less severe in the samples stored in ozone atmosphere compared to the control samples. Ozone in the storage atmosphere did not have any detrimental effect on anthocyanins and ascorbic acid contents of the fruit.