Application of MRI to monitor the process of ripening and decay in citrus treated with chitosan solutions

Chitosan is a biopolymer, which has numerous applications in agriculture and agroindustries. Coating fruit and vegetables with chitosan has some positive advantages for the long-term storage of foods, because the film of chitosan provides a kind of an active package, which allows a gradual release of preservatives, thus inhibiting fungal growth and maintaining the external appearance of the fruit for a longer time In this study, two varieties of citrus, Fortune mandarins and Valencia oranges were coated with Biorend® (IDEBIO S.L., Salamanca, Spain) (a compound whose active molecule is chitosan), to investigate its effect on maturity, decay, and damage, and therefore, to find a better method for the long term storage of fruit. The effect of chitosan as a fungistatic was also studied. To that end, the fruit was maintained in a damp storage room, ideal conditions for the growth of fungi. The magnetic resonance imaging (MRI) technique was used to monitor the process of ripening and decay in the citrus fruit that had been coated with chitosan. The dissolution of the chitosan on the mandarins and oranges produced excellent results in terms of percentage of weight loss, MRI, and visual appearance.