Effect of Homogenization and Pectin on Chemical, Textural, Antioxidant and Sensory Characteristics of L. bulgaricus-Fermented Oat-Based Product

The demand for plant-based fermented beverages is being driven by dietary restrictions, health concerns, and environmental concerns. However, the use of plant substrates, such as oats, presents challenges in terms of fermentation and texture formation. The effects of enzymatic hydrolysis, homogenization and the addition of 1% pectin on oat-based beverages fermented with <i>Lactobacillus delbrueckii</i> subsp. bulgaricus were evaluated in this study. The samples were evaluated for a number of characteristics, including physicochemical, rheological, antioxidant and sensory properties. After 6 h fermentation, pectin-containing samples showed a statistically significant decrease in pH (to 3.91) and an increase in titratable acidity (to 92 °T). Homogenization and the addition of pectin were found to significantly increase viscosity (by 1.5-2 times) and water-holding capacity (by 2 times) while reducing syneresis by 96%. The antioxidant activity of <i>L. bulgaricus</i>-fermented samples increased significantly: the radical scavenging activity (RSA) and OH-radical inhibition increased by 40-60%, depending on the treatment. Extractable polysaccharides (PSs) inhibited lipase and glucosidase by 90% and 85%, respectively; significantly higher inhibition was observed in the fermented and pectin-containing groups. Sensory evaluation showed that the homogenized, pectin-enriched samples (Homog+) scored highest for consistency (4.5 ± 0.2), texture (4.9 ± 0.2), and overall acceptability (4.8 ± 0.2); these scores were all statistically higher than those for the untreated samples. These results suggest that combining enzymatic hydrolysis, homogenization and fermentation with <i>L. bulgaricus</i> significantly improves the structural, functional and sensory properties of oat-based beverages, providing a promising approach to producing high-quality, functional non-dairy products.