Obtenção de umbu-cajá em pó pelo processo de liofilização e sua utilização no processamento de sorvetes prebióticos.

Abstract

Umbu-caja (Spondias spp.) has a characteristic taste and smell, being especially appreciated in places where it grows. Dehydrating this fruit to obtain a powder is an alternative to increase the supply to more distant markets from the production site and then incorporating it into ice cream formulas. In this context, this study aimed at producing umbu-caja powder through the lyophilization process, evaluating the stability of the powder during storage and producing a prebiotic ice cream with goat milk and umbu-caja powder. Seven formulas of umbu-caja pulp added to maltodextrin and guar gum (0, 10, 20 and 30%) were prepared. The formulated pulps were characterized and lyophilized on a bench top lyophilizer at -40°C for 48 h. The obtained powders were characterized and stored in laminated packages for 180 days under environmental temperature conditions (26.42°C) and relative humidity (80.8%), with analysis of physical, chemical and physicochemical parameters at the baseline and at every 30 days of storage. The hygroscopic behavior of powder pulps was also analyzed at the temperature of 30°C to determine the water adsorption isotherms. Goat milk ice creams were processed by varying the concentrations of umbu-caja powder (2, 4, 6, 8 and 10%), resulting in five formulations that were characterized regarding physical, chemical, physico-chemical, microbiological and sensorial parameters. We observed that the formulated and dehydrated umbu-caja pulps had their physical, chemical and physico-chemical characteristics altered by increasing additive concentrations. Storage promoted physical, chemical and physicochemical alterations to all samples, with increase in water levels and water activities, reductions of ascorbic acid, reducing sugars, titratable acidity and soluble solids, with darkening and reduced color saturation of the samples. Water adsorption isotherms were classified as type III, and among the mathematical models adjusted to the experimental data, the GAB model had the highest coefficients of determination (R2) and the lowest mean relative errors (P) for most of the studied samples. Increased concentrations of umbu-caja powder significantly altered physical, chemical and physicochemical characteristics of prebiotic ice creams, displaying conformity regarding their microbiological aspects. Improvement in sensory characteristics of the ice cream was found by increasing umbu-caja powder levels; the sample with the highest concentration of added powder had the highest positive purchase intention frequency.