Vegan Sesame Milk Ice Cream With Probiotic Bacteria (Lactobacillus casei) and Hibiscus (Hibiscus sabdariffa) Calyces Extract: Formulation, Characterization, and Stability

Abstract

In this study, probiotic ice cream was created using sesame seed milk and enriched with co-extruded microcapsules containing probiotic bacteria (Lactobacillus casei) and Hibiscus (Hibiscus sabdariffa) calyces extract. Results showed no significant difference in fat content between the control and enriched samples (both about 2.1%, p > 0.05). However, enrichment significantly reduced hardness (98 ± 2 N vs. 90 ± 2 N) and increased overrun (22.42% ± 1.2% vs. 28.42% ± 1.5%) and melting resistance (80.2% ± 0.5% vs. 88.2% ± 0.2%) (p < 0.05). The enriched ice cream contained higher anthocyanin (0.25 ± 0.01 mg/100 g vs. none detected in control), total flavonol (7.57 ± 0.1 mg/100 g vs. 0.7 ± 0.01 mg/100 g), ascorbic acid (0.14 ± 0.01 mg/100 g vs. 0.06 ± 0.01 mg/100 g), total phenolic content (3.72 ± 0.3 mg GAE/100 g vs. 0.25 ± 0.02 mg GAE/100 g), and antioxidant activity (31% ± 1.2% vs. 10.5% ± 2.5%) (p < 0.05). The viability of probiotic bacteria decreased over the 45-day storage period, reaching a logarithmic viable cell count of 6 ± 0.01 CFU/g at the end. While TPC content remained stable, anthocyanin, total flavonol, and ascorbic acid content showed significant decreases by the end of the storage (p < 0.05). In simulated gastrointestinal conditions, the logarithmic number of co-extruded probiotic bacterial cells decreased from 8 to 7.1 CFU/g after 1 h, and in simulated intestinal juice, the logarithmic viable cells reached 6.2 CFU/g. Sensory evaluation revealed a significant difference in appearance, flavor, and general acceptability between the control and enriched samples (p < 0.05), with the enriched samples scoring higher in these categories. In conclusion, this study demonstrates that co-extrusion technology effectively improves bioactive compound retention, probiotic stability, and sensory quality in plant-based probiotic ice cream.