Techno-Functional Assessment of Riboflavin-Enriched Yogurt-Based Fermented Milk Prepared by Supplementing Riboflavin-Producing Probiotic Strains of Lactiplantibacillus plantarum.

Vitamin enrichment in fermented dairy products through the intervention of vitamin-producing probiotic strains during fermentation is a novel approach in the field of probioceuticals. In this study, riboflavin-enriched yogurt-based fermented milk was prepared by mixing 1% (v/v) riboflavin-producing strain [1.2 × 10 8  CFU/mL of Lactiplantibacillus plantarum MTCC 25432 or L. plantarum MTCC 25433 or L. plantarum MTCC 25434] with 2% (v/v) traditional yogurt cultures [Streptococcus thermophilus NCDC 295 and L. delbrueckii subsp. bulgaricus NCDC 293; each of 1.3 × 10 7  CFU/mL]. The yogurt-based fermented milk prepared with traditional yogurt cultures (2%, v/v) was served as a control. The prepared yogurt-based fermented milk samples were analyzed and compared for riboflavin content, antimicrobial activity, physicochemical, and functional properties. As a result, the yogurt-based fermented milk prepared with L. plantarum MTCC 25432 produced a significantly higher amount of riboflavin (2.49 mg/L) as compared with MTCC 25433 (2.33 mg/L), MTCC 25434 (2.14 mg/L), and control (1.70 mg/L). The probiotic supplementation to yogurt cultures maintained the pH and titratable acidity in the range of 4.1-4.4 and 1.0-1.05% (lactic acid/100 mL), as recommended by Indian yogurt standards. The rheological, texture, and antimicrobial properties of yogurt-based fermented milk were enhanced with the addition of riboflavin-producing probiotic strains. Moreover, all yogurt-based fermented milk samples prepared in this study were acceptable as per the sensory evolution scores. In conclusion, the use of riboflavin-producing L. plantarum strains along with standard yogurt cultures could be the best approach to enhancing riboflavin content in yogurt-based fermented milk and fulfilling the daily riboflavin requirement in humans.