Cenouras minimamente processadas com cobertura de amido reforçada com suspensões de celulose micro/nanofibrilada obtidas de cenoura

Abstract

This work was carried out in order to prepare edible and biodegradable films from mixtures of corn starch plasticized with glycerol and enhanced with suspensions of cellulose micro/nanofibrils (CMNF) obtained from carrot, producing a biocomposite as well, to study the effect of applying these films as a coating on the physical and chemical characteristics of minimally processed carrots and stored in controlled temperature and relative humidity. Suspensions of CMNF was obtained from carrot by a mechanical process, as alternative to the better utilization of the vegetable, contributing to the reduction of post-harvest losses since it is possible to use wilted carrots or pattern of unacceptable quality for market. Suspensions of carrot CMNF provided better characteristics such as barrier property and mechanical properties to the starch films. The use of starch coating reinforced with suspensions of carrot CMNF was responsible for a further decrease of mass loss. The starch coating reinforced with suspensions of carrot CMNF was also effective in decreasing respiratory rate, preventing whitening and keeping the total antioxidant activity, total amount of phenolic and organic acids of the minimally processed carrots. Minimal processing of carrots was carried out with satisfactory hygienic and sanitary practices, since the minimally processed carrots showed no significant counts of filamentous fungi and yeast and showed no Salmonella sp. and coliforms at 35 to 45°C and are therefore also free from Escherichia coli. The use of edible coating of starch enhanced with suspension of CMNF obtained from carrot promotes increased shelf life of minimally processed carrots.