Block Freeze Concentration Processes for Goat Milk Aiming at the Elaboration of an Innovative Functional Fermented Milk

The development of functional dairy products has increasingly become a focus of the dairy industry, with goat milk gaining prominence due to its nutritional properties and digestibility. This study aimed to evaluate the effects of freeze concentration processes on skimmed goat milk, observing its potential prebiotic effects and impacts on the physical, chemical, microbiological, rheological, and sensory profiles of fermented milk, using the Preferred Attributes Elicitation (PAE) methodology. Skimmed goat milk was initially concentrated using the gravitational block freeze concentration technique. A fermented milk containing probiotics (FM1) was produced from this concentrate. In addition, two other samples were developed: one with skimmed goat's milk, 6% inulin, and probiotics (FM2) and another using whole goat's milk with probiotics as a control (FM3). The results indicated that the freezing concentration process resulted in a concentrate with 14.70 +/- 0.06 g 100 g-1 of total solids. Among the three types of fermented milk, FM1 presented the highest values of total solids and titratable acidity. Regarding color, both FM1 and FM2 tended towards yellowish and greenish tones, while FM3 presented a greater luminosity. During storage, all fermented milks maintained their probiotic properties. The freeze concentration process increased the viscosity of FM1, a characteristic also evidenced in the sensory evaluations using PAE. In contrast, FM2 presented a rheological behavior similar to that of the control (FM3). Regarding sensory acceptance, FM1 had lower acceptance regarding aroma, being described as having notes of "goat flavor" and "acid" and being "salty". The PAE methodology proved effective in characterizing the sensory qualities of the products, providing valuable information for developing new dairy products. These results offer an important theoretical basis for the industrial production of functional dairy products based on goat's milk, helping to evaluate quality characteristics and optimize manufacturing processes.