Modified atmosphere packaging of sweet cherries with biodegradable films

The effect of Modified Atmosphere Packaging (MAP) with biodegradable films (Film 1: 25 μm thickness; O2 TR 3000 cm³ m^-2 day-1 atm^-1; Film 2: 25 μm thickness O2 TR 900 cm³ m^-2 day^-1 atm^-1) on preserving sweet cherry fruit quality during cold storage was evaluated. The biodegradable films were compared with a control film of polyethylene (25 μm thickness; O2 TR 8000 cm³ m^-2 day^-1 atm^-1). Gas composition inside the packages, parameters related to quality (firmness, colour, Total Soluble Solids content, Titratable Acidity) and changes in bioactive compounds (total polyphenols, total anthocyanins and total antioxidant activity) were analyzed during 15 days of cold storage at 1°C. The data showed that the use of biodegradable films was useful to preserve quality of cherries through a delay in the changes in colour and the losses of firmness and acidity. Film 2, characterized by an high permeability to CO2 and high barrier to O2 provided the best results in terms of colour, acidity and firmness. With respect to anthocyanins content, phenolics contents and total antioxidant activity, differences existed among the three treatments (control, Film1, Film 2) but was detected any negative effect due to biodegradable films. The results suggest that biodegradable polymers could be used in packaging of sweet cherries without negative effects on final quality.