Fermentation of Dietary Fibre-Added Milk with Yoghurt Bacteria and L. rhamnosus and Use in Ice Cream Production

This study investigated whether the use of fermented milk with added dietary fibre in ice cream production positively affected quality characteristics, especially viability, during a shelf life of 90 days at −25 °C. For this purpose, fermented milk was prepared with cultures (yoghurt and Lacticaseibacillus rhamnosus) and dietary fibre (wheat fibre and inulin). In addition to the viable cell count, some related quality characteristics, such as the sensory, physical, chemical, and thermal properties, and energy content were also examined. Streptococcus salivarius subsp. thermophilus in all yoghurt ice creams and L. rhamnosus in ice cream with wheat fibre had the highest viability for 90 days, up to 95.95%. The best scores regarding “general acceptability” belonged to the ice cream with L. rhamnosus and inulin, with a score of 7.81 out of 9. The dietary fibre decreased overrun from around 23% to 14–18%, which was positive for the viability of the cultures. The cultures and dietary fibre decreased the melting temperature down to −1.15 °C. The caloric value of the ice creams (166–168 kcal/100 g) was lower than that of standard ice cream. Probiotic ice cream production with dietary fibre and a single L. rhamnosus culture may be preferred in terms of sensory properties, cell viability, and economic aspects.