Liofilização de polpa de manga (mangifera indica l.) c.v tommy atkins: condições de secagem e estabilidade

Abstract

The objective of the research was to evaluate the drying in freeze dryer of Tommy Atkins mango pulp, determining its drying conditions, quality parameters and stability. The drying condition was evaluated by the influence of the maltodextrin concentration and the lyophilization time on the moisture, yield, hygroscopicity, ascorbic acid concentration, solubility and color of the powders, using a complete factorial design 22. The whole pulp was characterized (Moisture, water hygroscopicity, ascorbic acid, solubility, carotenoids, phenolic compounds), colorimetric and morphological parameters (fluidity, density and effective angles and attrition angles with the wall). From the results of the planning, the use of 10% of maltodextrin and 24 hours of lyophilization was determined as the best drying condition. The morphology study revealed differences in the surface and shape of the particles with higher concentration of the drying adjuvant and that the powders obtained are amorphous. Mango powders with 5% maltodextrin were cohesive and 10% and 15% easy flow. The density increased to 691.3 kg / m 3, due to the increase in maltodextrin, whereas the internal friction and friction angles with the wall decreased for the three concentrations (5, 10 and 15%), improving the flow of the Powders. The GAB model was the one that best adjusted the adsorption isotherms of the mango pulp powder, and the increased addition of maltodextrin led to less hygroscopic powders. The stability of the lyophilized powder stored in two different containers (polyethylene and laminate) during 90 days allowed to identify that polyethylene did not prevent the absorption of water, with a 94% increase in humidity and 68% in water activity. The color coordinate b * suffered reductions of up to 29% during the period, but the predominance of yellow color was maintained. There was an average reduction of 50% in the ascorbic acid contents of the samples for both packages. The use of the vacuum-laminated package proved to be effective as a barrier against moisture absorption during storage of the powders. In general, drying can be concluded in lyophilizer resulting in mango pulp powder with satisfactory physical and chemical-physical characteristics and that the use of maltodextrin improves the morphological characteristics of the particles, decreases the hygroscopicity and allows a better flow of powders.