Sustainable development of dairy-based functional beverages enriched with bee pollen: a circular economy approach

Abstract

The growing demand for sustainable and functional foods has driven the development of novel formulations that both valorize dairy co-products and incorporate functional ingredients. Six fermented dairy beverages were developed by partially replacing skim milk (0–75%, w/w) with buttermilk and/or sweet cheese whey. The formulations were enriched with 1% bee pollen, banana, and honey, fermented using a commercial yogurt culture, and stored at 4 °C. We evaluated the proximate composition, pH and titratable acidity, water-holding capacity (WHC) and syneresis, antioxidant activity, colloidal stability (Turbiscan Stability Index – TSI), rheological behavior, texture, and sensory properties. All formulations exhibited similar acidification profile during storage (pH change from 4.45 to 4.15 and acidity from 0.82 to 0.92% lactic acid over 30 days), indicating unaltered lactose fermentation despite milk replacement. Formulations containing 37.5% of buttermilk or whey achieved higher WHC (>60%) and lower syneresis (∼9–10%), correlating with low TSI values (<0.9) and pseudoplastic rheology. Textural analyses showed that the same formulations achieved a balance between gel strength and cohesiveness, without compromising adhesiveness or elasticity. Antioxidant assays revealed that 75% buttermilk samples exhibited the greatest radical-scavenging activity (DPPH: 72.5 ± 2.1%; ABTS: 63.8 ± 1.9%), underscoring the influence of polar lipids on functionality. Sensory tests pointed to the high acceptance of moderate-replacement samples, linked to creamy, sweet, yogurt-like attributes, whereas 75% whey samples scored lower due to bitterness. Overall, moderate substitution with buttermilk or whey, combined with bee pollen enrichment, produces stable, antioxidant-rich, and consumer-acceptable beverages, supporting functional food development and the circular economy in the dairy sector.