Abstract:
In order to extend the shelf life of frozen fruits, the effects of chitosan or chitosan-beewax composite coatings on physiology and quality of frozen yellow-flesh peach slices (Prunus persicu L. Batsch.) were investigated during 60 days of storage at -20℃. Polyphenol oxidase (PPO) activity, membrane permeability, firmness, color, vitamin C, drip loss and soluble solids of the frozen products were evaluated. The chitosan and the chitosan-beewax composite coatings exhibited a positive effect on vitamin C retention, delayed the increases in PPO activity and relative electrolyte rates, reduced browning and drip loss compared with the uncoated control. The chitosan-beewax composite coating seems to be more promising for reduction of losses of drip, firmness and vitamin C.