Investigation on the possibilities of yoghurt production from oat milk pasteurized by thermal and non-thermal processes

The aim of this study was to produce set-type non-dairy yogurt from oat milk pasteurized by thermally (T) and UV-C (a coiled-tube type) assisted thermally (UV-C+T) processes. The yogurts were produced from untreated, T (63 °C, 30 min) and UV-C+T treated (10 cycles, 77.67 J/mL, 60 °C) oat milk by lactic acid fermentation and their microbiological, physicochemical, textural and sensorial changes monitored for 21 days. The reduction of E. coli K-12 was ca. 5 log cfu/ml for both T and UV-C+T treated samples. Yogurts from UV-C+T treated oat milk has the highest pH (5-6) and the lowest syneresis value during the storage time. L* (60.9 ± 0.1) and b* (4.9 ± 0.1) values of yogurts from UV-C+T treated oat milk were lower compared to untreated and T treated oat milk. Yogurts of UV-C+T treated oat milk had higher hardness (g) and adhesive forces (g) values than the ones of untreated and T treated during the storage time. Moreover, there was no significant difference (P<0.05) in terms of overall acceptability of yogurts of untreated, UV-C+T and T treated oat milk. Results showed that the use of UV-C+T treated oat milk has a potential for improving the characteristics of the final product.