Secagem por aspersão da manga cv. Haden e armazenamento do pó.

Abstract

Food industry uses some processes to transform fruit pulp in other products, as an example of these processes there is spray drying. The objectives of this study were to dehydrate by spray dryer the mango cv. Haden pulp formulated to evaluate the powder sample selected during storage at controlled temperatures and humidity; as well as analyze the moisture adsorption isotherms of the best formulation. Formulations were prepared with mango pulp and maltodextrin in different concentrations (30, 35 and 40%); and dehydrated by spray dryer at temperatures of 150, 170 and 190 °C. Drying was used for experimental design, with the 2² factorial with 3 repetitions in the central point (level 0) and 4 combinations of +1 and -1 levels resulting in 7 experiments. To the full mango pulp, formulations and the powders obtained through spray drying, the following physico-chemical analysis were conducted: water activity, moisture content, total solids, ashes, total, reducing and nonreducing sugars, proteins, insolubility, pH, total titratable acidity, total soluble solids, ascorbic acid, density and reconstitution time. The storage for 60 days of the selected powder (Experiment 2 - 40% of maltodextrin and drying at 150 °C; Experiment 4 - 40% maltodextrin and 190 °C drying temperature) was carried out at temperatures of 30 and 40 °C, with relative humidity of 55%, in laminated packing. Moisture content, water activity, pH, total titratable acidity, ascorbic acid, insolubility, reducing sugars and color were evaluated. The moisture adsorption isotherm of the selected powder was determined in Experiment 4 (40% maltodextrin and drying temperature of 190 °C) at temperatures of 20, 30 and 40 °C and GAB, Peleg and Oswin models were adjusted to the experimental data. Powder selection ocurred according to the experimental design, mainly through moisture content parameters, yellowness and ascorbic acid. It was noticed that the model that best suits isotherms is the GAB, categorized as isotherms of Types II and III. In the storing, there was moisture content, water activity and pH increase over time for two types of powders at the two temperatures; the full Haden mango pulp was classified as acidic and the drying chamber powder resulted in a darker color than the cyclone dust.