Effect of Spirulina platensis fortification on physicochemical, textural, antioxidant and sensory properties of yogurt during fermentation and storage

- Yogurt with Spirulina had a higher protein, fat and dietary fiber contents.
- Yogurt supplemented with 0.25% of Spirulina gave closer results to control sample for textural and sensory evaluation.
- This treatment also exhibited significant better water holding capacity and lower whey syneresis during storage.
- Spirulina can be used as a natural ingredient to develop a novel yogurt with high nutritional properties.

Due to the high consumption rate of fermented milk products such as yogurt, the fortification of these products will effectively reduce diseases associated with nutritional deficiencies. In the present study, after incorporating Spirulina into yogurt at four different concentrations (0.25, 0.5, 0.75 and 1%), we studied its effect on the fermentation process, texture, nutraceutical and sensory characteristics of yogurt. The addition of 0.25% of Spirulina was significantly sufficient to accelerate the end of fermentation (p < 0.05) and conserve the textural properties and sensory acceptability of the final milk product. This treatment also exhibited significant better water holding capacity and lower whey syneresis during 28 days of storage. During this period, the colored yogurt showed negligible variations for the L*, a* and b* indices, reflecting the strong stability of Spirulina color. Thanks to its high content in pigments, Spirulina considerably improve the antioxidant activity of the new formulated yogurt. Overall, it can be concluded that Spirulina can be used as a natural ingredient to develop a novel yogurt with high nutritional properties.