The effect of edible coatings and polymeric packaging films on the quality of minimally processed carrots

Minimally processed carrots have a short shelf-life because of white blush formation (caused primarily by surface dehydration) and microbiological spoilage (caused mostly by lactic acid bacteria). The use of polymeric packaging films combined with edible coatings might have an additive or synergistic effect to extend the shelf-life of minimally processed carrots because of the formation of a double barrier to gases and water vapour. A 3 x 3 factorial experiment using a polymeric packaging film of three different levels of permeability and a cellulose-based edible coating (Nature Sealo) at different concentrations was conducted on minimally processed carrots to investigate any possible synergistic effect over 12 days of storage at 10degreesC. No such effect was found. The polymeric packaging film effectively prevented microbiological growth and spoilage but was unable to control white blush formation. On the other hand, the edible coating partially controlled white blush formation but enhanced microbiological spoilage. The polymeric packaging film functioned primarily as a gas barrier, whereas the edible coating probably functioned as a moisture barrier. White blush formation was found to be the most important shelf-life determinant for minimally processed carrots. (C) 2003 Society of Chemical Industry.