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In this research, foaming technology was applied to obtain powdered yogurt from commercial yogurt at lower temperatures than the typical temperatures used during the dehydration process; the viability of lactic acid bacteria (LAB) was evaluated after the application of different drying techniques (conventional drying, freeze drying, and vacuum drying). Three different formulas (F1, F2, and F3) based on a foaming agent (albumen), stabilizers (guar gum), and prebiotics sources (inulin and agave syrup) were developed. Foam stability was evaluated at different pH values through optimum time of foam (OTF), medium drainage time (MDT), and drainage volume (DV). Foam expansion (FE) and foam density (FD) were measured. The OTF ranged from 6 to 10 min. The MDT ranged from 4.3 to 27.3 min, depending on pH, while the DV varied from 14.1 to 16.2 mL only in F1. No drainage was evidenced in F2 and F3, showing the best stability. The F2 and F3 produced the best FE and FD values. The dried yogurt with different techniques showed a survival rate (SR) of up to 85% Log-CFU/mL, even with the conventional drying method. Sensorial trials were carried out in reconstituted product, with the freeze-dried yogurt showing higher scores. The foam formulas developed demonstrate the efficacy of both the dehydration of yogurt and the preservation of LAB.

In this study, a flour from corn cob (central core of the maize ear, stage R4) was obtained through three treatments. The three flours obtained were characterized by bromatological analysis, yield, and granulometry. Additional dressing-type oil in water (O/W) emulsions were developed, varying the formulation by incorporating distinct amounts of corn cob flour. The formulations' stability was evaluated over a period of 21 days, determining the particle size, creaming index, coalescence rate, consistency coefficient (k), and flow behavior indices (n). Results have shown significant differences in protein, fat, and carbohydrate content in the flour, depending on the cooking treatment. A good percentage of grinding yield was obtained (98%), in addition to several fractions by granulometry (60, 120, 250 MESH), showing differences in their nutritional content. Finally, the particle size of O/W emulsions developed varied among formulations. The combination of 0.6% of xanthan gum (XG) and corn cob flour showed major stability in average droplet size. No significant differences were observed in the coalescence rate values for the three formulations. Still, significant differences in the creaming index were evidenced in those formulations without XG or corn cob flour. The results regarding the consistency coefficient (k) and flow behavior indices (n) suggest a possible synergy between XG and flour of corn cob for enhancing the viscosity and pseudoplasticity of dressings in a concentration-dependent manner.