Edible coating effect study and intermittent drying on the dried mango quality

Abstract

The purpose of this project is to investigate methods from the edible coatings combinations and convective drying, applied to the mango, with the aim of increasing quality of dried product comparing to conventional drying. The mango (Mangifera indica L.) is a tropical fruit with high nutritional content and has broad market acceptance. Films and edible coatings comes is showing promise in many applications aimed at improving the food quality, both the protective effect as the load ability and to release interest substances. Therefore, the specific objectives of this work are: to develop and to characterize complex films of soy protein isolate + pectin; to evaluate the effects of their application as edible coating in mango pieces on the drying kinetics; to evaluate the reduction of drying time by applying thermal intermittently. In a first step, different formulations of soy protein isolate and pectin will be evaluate. For this, the films will be characterize according to their solubility, morphology, mechanical properties, thermal properties, transparency, hygroscopicity, permeability to water vapor and permeability to gases (CO2 and O2). In the second step, a formulation will be select to coat the mango pieces will be dry until the fruit reaches an intermediate moisture pre-established. It will evaluate the influence of this edible coating on the drying efficiency and physical and nutritional qualities of the fruit. It will also be evaluate heat intermittently applying in order to reduce the drying time and improve the dried food characteristics. The thermal intermittently consist of changing the time and temperature conditions during drying, using higher temperatures while the product surface is partially saturated. The process will be optimize from a factorial design based on the determination of drying kinetics and color and nutrients retention, more specifically, vitamin C and carotenoids.