Effects of Chia Seed Levels on Quality and Bio-Functional Profile of Stirred Yoghurt

Abstract

Yoghurt is considered as a healthy food. Thus, it could convey functional and bioactive ingredients. Chia seeds are of great interest due to their ability to improve consumer health. In this study, chia seeds were added to stirred yoghurt at different doses (1.5, 3, 4.5, or 6%). The effects of chia seeds on physicochemical, microbiological, and sensory qualities were assessed during 28 days of refrigerated storage. The results showed that chia seeds slightly decreased post-acidification, the lowest value was obtained in yogurt with 3% chia seeds (24°D), but syneresis rose significantly (P<0.05) when 6% of chia seeds was added. Furthermore, chia seeds promote viability of yoghurt bacteria, and antioxidant activity reached 62.20±0.02% in yoghurt added with 1.5% chia seeds. However, proteolysis is not affected. The effects of chia seeds were not dose dependent as 4.5% and 6% did not follow trend. These findings were affirmed by sensory characteristics. Thus, stirred yoghurt containing 1.5 or 3% of chia seeds proved to be the most adequate choices.