Effect of glucose oxidase on the preservation of raspberries

Testing several natural preservatives for their effectiveness, using raspberries as samples. Harvested raspberries were treated with four kinds of natural preservatives including 0. 1 % glucose oxidase + 0. 1 %glucose, 0. 05 % lysozyme, 0. 1 % glucose oxidase + 0. 1 % glucose + 0. 1 % chitosan, 0. 05 % lysozyme + 0. 1 %chitosan, or distilled water as a control. All groups were preserved at 4℃ under polyethylene film. Changes in physiological and biochemical indices were determined periodically during storage, including rot rate, weight loss rate, soluble solids content, browning degree and hardness. We report here that 0.1% glucose oxidase +0.1% glucose+0.1% chitosan was the most effective treatment for comprehensive preservation. After 12 days of storage under this combination of preservatives, rot rate was 13.26%, weight loss rate was 10.57%, and soluble solids content was 10.8%, while inhibition of browning and maintenance of hardness and itritable acidity content were better than in the other treated groups with a statistically significant difference (p<0.05) compared to the control.