Evaluation of physicochemical, microbiological, and antioxidant properties of a drinkable yogurt added with ultrasonicated purple cactus pear (Opuntia ficus-indica) juice powder

The objective of this study was to compare drinkable yogurts added with purple cactus pear powder without ultrasonication (WY) and ultrasonicated (UY); with formulated yogurt with synthetic dyes (DY) and commercial saborized yogurt evaluating pH, titratable acidity, water holding capacity, viscosity, color, microbiology and in vitro bioaccessibility of antioxidants. The WY and UY showed an increase in functional properties, high ascorbic acid, and phenolic content (129.83 and 57.27 mg AAE/100 ml; 26.64 and 22.87 mg GAE/100 ml, respectively). The UY increased the antioxidant activity measured by ABTS (6.41 +/- 0.11 mg VCEAC/100 ml) and DPPH (38.38 +/- 0.92 mu M TE/100 ml) in comparison to WY. After bioaccessibility assay, the UY had high phenolic content and antioxidant activity by ABTS, just below DY which presented the major content with respect to the other samples. The ultrasonicated purple cactus pear powder addition could be an alternative to drinkable yogurt with bioaccessible antioxidants. Practical applications The benefits of yogurt make it a popular food with high consumption by its nutritional aspect, mainly if the product has natural additives that provide antioxidant compounds related to beneficial health effects, such as heart disease, diabetes, cancer, and among others. The different raw matter of purple cactus pear juice powder could provide an intense color as a natural additive to dairy products such as yogurt, which can be an alternative to synthetic additives since they play an important role in the quality of the product and consumer acceptance. In addition, the yogurt added with purple cactus pear juice powder also provides antioxidant content and high bioaccessibility, with light changes in their physicochemical characteristics.

Automated summary

The study compared the drinkable yogurts added with purple cactus pear powder with and without ultrasonication, showing that ultrasonicated yogurt had higher antioxidant activity and better bioaccessibility, serving as a potential natural source of antioxidants.