The Effect of Using Different Strawberry Varieties in Probiotic Yoghurt Production on Sensory and Biochemical Characteristics and Bacterial Viability of the Product
Project no. 20438 · Status: Kapanmış · 2019
Summary
<p>In the study, the chemical, microbiological, sensory and some biochemical characteristics of pulp prepared from different strawberry varieties (Albion, Camarosa, Rubygem) and <em>Bifidobacterium animalis</em> subsp. <em>lactis</em> added probiotic yoghurts were investigated during 21 days of storage. While yoghurt without strawberry pulp was the control group, pulp was added to the other product groups at the rate of 15%. In addition, chemical, physical and biochemical properties of strawberry varieties were determined. There were no statistical differences between strawberry varieties in terms of vitamin C (p>0.05). In terms of total phenol content, antioxidant activity and total anthocyanin content, the highest values were found in Albion strawberry variety, while Rubygem strawberry variety had the lowest values.</p><p>Titration acidity of probiotic yoghurts showed values in accordance with Turkish Food Codex Fermented Milk Communique during storage. The highest <em>Streptococcus thermophilus</em> viability was determined in yoghurt containing Albion strawberry variety on the 1st and 7th days of storage. <em>Lactobacillus bulgaricus</em> viability was higher in probiotic yoghurts containing Albion and Camarosa strawberry varieties during 14 days of storage, with the lowest in the control sample during 21 days of storage (p<0.05). In terms of sensory properties, it is seen that all yoghurt samples are highly accepted and appreciated. On the other hand, the addition of strawberries to yoghurt increased the viability of <em>B. lactis </em>compared to the control group, and the minimum 6 log cfu/g level determined for the number of live probiotic bacteria was preserved in all yoghurts during storage. The highest total phenolic content and antioxidant activity during storage were determined in yoghurt containing Albion strawberry variety. This situation is in parallel with the results of total phenol content and antioxidant activity analysis of strawberry varieties.</p>