Utilização de cobertura comestível a base de pectina de baixa metoxilação e ácido cinâmico em morango refrigerado

Abstract

This study had as objective to evaluate the edible coating influence of low methoxyl pectin and cinnamic acid in chilled strawberries in natura, being analyses microbiological and physical-chemical in order to verify the influence of the treatments on quality post-harvest and microbiological safety of fruits. Five formulations were developed and the variable was the addition of antimicrobial agent cinnamic acid (control, 50 mg L-1, 100 mg L-1, 150 mg L-1 e 200 mg L-1). It was fixed an edible coverage formulation of low methoxyl pectin (10 g L-1). The statistical design used was entirely randomized with three repetitions per treatment on each day of analysis. After the immersion of strawberries in the formulations (coverages), the fruits were put up in packaging of expanded polystyrene covered with polyethylene film and stored at 5 °C and 85-90 % relative humidity for a period of 10 days. The microbiological analysis total count of mesophilic , psychrotrophic, yeasts and molds and total coliforms were performed at 0, 3, 6 and 10 days of storage and the physical-chemical analysis of loss of fresh pasta, coloring, activity of water, pH, content of soluble solids (°Brix) and titratable acidity were performed at 0, 2, 4, 6, 8 and 10 days of storage. The obtained data were subjected to analysis of variance and the averages compared by the test of Tukey 5% of probability. Among the treatments, the fruits with the best characteristics post-harvest were treated with 150 mg L-1 of cinnamic acid. Only the fruits treated with 50 mg L-1 of cinnamic acid were unfit to be consumed in the tenth day of storage, due to the high count of mesophilic and psychrotrophic.