Valorization of acid whey in a probiotic orange–based beverage containing microencapsulated Limosilactobacillus fermentum: physicochemical, rheological, microbiological, and temporal sensory characterization

This study aimed to develop and characterize an acid-whey–orange beverage containing Limosilactobacillus fermentum 4–17, with emphasis on physicochemical, rheological, microbiological, and temporal sensory properties during refrigerated storage. Five formulations were evaluated: an orange-juice control (A), three formulations containing 10, 20, or 30% (v/v) of a reconstituted acid-whey preparation together with microencapsulated cells (B–D; W10:P90, W20:P80, and W30:P70), and an orange-juice formulation containing non-encapsulated cells (E). Whey-containing formulations showed higher pH, estimated protein content, dry matter, and apparent viscosity than the control at several sampling points ( p < 0.05). All formulations showed an apparent shear-thinning pattern across the instrument-reported shear conditions, while the magnitude of storage-related viscosity changes depended on formulation and shear condition. After 21 days at 4 ± 1 °C, culturable lactic acid bacterial counts in the whey-containing encapsulated formulations ranged from 7.71 to 8.50 log₁₀ CFU/mL, compared with 6.81 log₁₀ CFU/mL in the non-encapsulated orange-juice formulation. Because whey level and probiotic incorporation mode were not varied independently, these differences should be interpreted as formulation-associated and do not establish an isolated effect of microencapsulation. Temporal dominance of sensations (TDS) showed formulation-dependent changes from fruity/sweet toward sour dominance during storage; formulations B and C retained a comparatively more balanced temporal sensory profile. TDS was performed with trained panelists and therefore does not constitute consumer-acceptability testing. Overall, the study supports the feasibility of acid-whey valorization in a probiotic fruit-based beverage while identifying matrix composition, probiotic recovery, and consumer validation as priorities for further work.