Total phenols, antioxidant activity and microbiological quality of ozone sanitized blackberry (Rubus spp. L.)

Abstract

Regular research conducted has associated the consumption of fresh fruits to beneficial effects on health, but microbiological quality must be ensured. The objective of this study was to verify the effect of ozone as a sanitizing agent and evaluate the impact of treatment on the content of phenolic compounds, antioxidant activity, color and microbiological quality of blackberry (Rubus spp. L.) Tupy cultivar. The total coliforms and at 45ºC, Salmonella, yeasts and molds, content of total phenolic compounds, antioxidant activity, color and pH of the samples were evaluated. The values obtained for total phenols, antioxidant activity and color test were not significantly different (p>0.05) between the control treatment, and those where the ozone was applied for 30s and for 3 min. However, sanitization with a solution of sodium hypochlorite caused a significant reduction (p#0.05) for the hue angle in relation to the in natura sample (control). It was concluded that the treatment in which ozone was used as a sanitizer for 3 min, was the most effective in reducing the microbial load of yeasts and molds, followed by the treatment with sodium hypochlorite solution and ozone for 30 s.