Evaluation of the Technological and Functional Properties of a Fermented Hemp Seed Product and Its Application in a Fermented Dairy Drink

The development of innovative fermented beverages relies on microbial fermentation to enhance the nutritional and functional potential of plant-derived ingredients. This study aimed to evaluate the effects of lactic acid bacteria (LAB) fermentation on the composition, technological and functional properties of a fermented hemp seed product (FHSP), and to assess its suitability for fermented dairy drink enrichment. The hemp seed product was fermented with Lacticaseibacillus paracasei, Lactiplantibacillus plantarum, or Limosilactobacillus fermentum. LAB growth, acidification, technological properties, bile- and cholesterol-binding capacities, total phenolic content, and antioxidant activity were determined. The selected FHSP was incorporated into fermented dairy drink, which was evaluated for physicochemical and sensory properties. LAB counts increased during the first 48 h and stabilised after 72 h. L. paracasei showed the highest viability during fermentation (1.38 × 109 CFU/g) and after freeze-drying (9.02 × 108 CFU/g). Fermentation increased water swelling capacity and, depending on the strain, water retention capacity. The L. fermentum FHSP exhibited the highest bile-binding capacity, whereas the products fermented with L. paracasei and L. plantarum showed the highest total phenolic content and ABTS radical-scavenging activity. Considering its highest LAB viability together with its high total phenolic content and DPPH radical-scavenging activity, the L. paracasei FHSP was selected for fermented dairy drink enrichment. Increasing its level significantly enhanced total phenolic content and antioxidant activity but also increased syneresis and darkened the product. The drink containing 4 g/100 g of FHSP received the highest sensory scores. Overall, LAB fermentation improved the technological and functional potential of hemp seed product and supported its use in fermented dairy beverages.