Obtenção do leite de cabra em pó com diferentes concentrações de polpa de cajá.

Abstract

This work aimed the study of physical and chemical components of yellow mombin, goat milk, composed formulations of goat milk and different concentrations of yellow mombin (0, 10, 20 and 30%) and the powder product obtained by freeze-drying process of goat milk formulations with different concentrations of yellow mombin, the kinetics of freezing under temperatures of -20, -30, -170 and -196 °C of the formulations, the kinetics of freeze-drying of the formulations; the isotherms of equilibrium moisture content of the powder porducLs under temperatures of 20, 30, 40 and 45°C and sensory evaluation of the formulations concerning to aroma, flavor, appearance and color. The characterization of the yellow mombin, goat milk, formulations and the powder lyophilized product, was performed according to methods recommended by the legislation (Brazil, 2000a), (Brazil, 2000b) and (Brazil, 2005), the kinetics of freezing of the formulations were carried out in conventional freezer (-20 and -30 °C) in liquid nitrogen vapor (-170 ° C) and immersion in liquid nitrogen (-196 ° C), the kinetics of freeze-drying were determined in a lyophilizer Terroni Fauvel Brand, the isotherms of equilibrium moisture content in Thermoconstanter Novasina, while the sensory analysis was performed using multiple comparisons on a hedonic scale. The values of physico-chemical pulp, hog and goat milk are in accordance with current legislation, except for the values of non fat solids and lactose from goat milk. The values of water content, total acidity, reducing sugars and non reducing sugars of the formulations composed by goat milk and yellow mombin, increase with the addition of yellow mombin, whereas the values of total solids, protein content soluble solids, lipids and pH decreased with the addition of yellow mombin. The powder formulations were maintained in accordance to the law, for the modified powder milk and literature. The addition of yellow mombin formulations reduced the time of freezing under -20 °C, -30 °C, -170 °C and-196 °C, respectively and increased the average effective thermal diffusivity. The addition of yellow mombin to goat's milk increased the drying time in which the formulations with 0, 10, 20 and 30% of yellow mombin showed drying times at 36, 40, 48 and 52 h, respectively. We considered the mathematical model proposed by Cavalcanti Mata the one that best predicts the behavior of drying, the model of Henderson was the one that had a better adjust to the experimental data of isotherms of moisture equilibrium for the different formulations of goat milk powder dried with yellow mombin with the curves of equilibrium moisture content with a typical behavior of type III isotherms. Through the acceptance test, an increase in the values assigned to the flavor, aroma and appearance was noticed, while the concentration of yellow mombin in goat milk also increased.