Acta Scientiarum Polonorum Technologia Alimentaria

Background. The aim of the study was to determine changes in the physicochemical and rheological proper­ties, antioxidant activity and sensory attributes of stirred yogurts containing hawthorn composite (HC).
Materials and methods. In this study, the peel and pulp of hawthorn were used to obtain a composite which was incorporated into stirred yogurts in different concentrations (0.0 to 0.5% w/w) coded as Y0, Y0.1, Y0.3 and Y0.5. Acidification kinetics during yogurt production were evaluated, as well as sensory attributes at day 5 of storage, antioxidant capacity, physicochemical and rheological properties at days 1 and 21.
Results. Addition of 0.5% HC decreased the fermentation time from 8 (Y0) to 5.80 h (Y0.5). The incorpora­tion of HC generated higher protein, ash, and fiber concentrations in the yogurts. The syneresis of the yogurts with added HC decreased by 18.0% compared to Y0. The flow behavior of the yogurts was described by the Ellis model (R² = 0.99), where η0 and λ exhibited higher values as the HC concentration increased. The highest percentage of inhibition was 53 ±1.50 % (Y0.5), and the lowest was 39.57 ±0.62 % (Y0), maintaining antioxidant activity at the end of storage. Yogurts Y0.1 and Y0.3 obtained an overall acceptability of 3.92 ±0.79 and 4.12 ±0.72 on a 5-point scale.
Conclusion. These results suggest that hawthorn composite (HC) can serve as a functional ingredient in fermented dairy products such as stirred yogurt. The addition of HC reduced total fermentation time and improved the yogurt’s physicochemical, antioxidant and sensory properties.