Color degradation kinetics in low-calorie strawberry and guava jellies

Abstract

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The purpose of this study was to follow-up color changes in low-calorie strawberry and guava jellies during storage. To this end, one formulation of each flavor was prepared varying the application of hydrocolloids (pectin and modified starch). The jellies were studied regarding pH, soluble solids, water activity and syneresis. In order to follow-up color changes, the samples remained stored for 180 days in chambers with controlled temperatures of 10 degrees C (control) and 25 degrees C (commercial), and color instrumental analyses (L*, a*, and b*) were performed every 30 days. Arrhenius model was applied to reaction speeds (k) at different temperatures, where light strawberry and guava jellies showed greater color changes when stored at 25 degrees C compared to the samples stored at 10 degrees C. Activation energy values between 13 and 15 kcal.mol(-1) and Q(10) values between 2.1 and 2.3 were obtained for light strawberry jelly and light guava jelly, respectively. Therefore, it was concluded that, with respect to color changes, every 10 degrees C temperature increase reduces light jellies shelf-life by half.313758764Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq