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Effect of sonication on the quality parameters of juçara, banana and strawberry smoothie was evaluated using a rotational central composite design with power (73.5-250.0 W) and time (7-36 min) as independent variables. The sonicated smoothie was evaluated regarding anthocyanins, instrumental color and rheological and physicochemical parameters. Within the evaluated processing conditions, 86% of anthocyanins were retained. The pH and acidity of the smoothie wasn't affected by the independent variables. Regarding instrumental color parameters, only luminosity was affected by the operational conditions. The cavitation phenomenon decreased the apparent viscosity of the smoothie. The sonicated smoothie presented non-Newtonian behavior, with characteristics of a pseudoplastic fluid (n < 1) in all treatments and control. Taking into account that the highest anthocyanin retention was observed at 147 W for 2 min, this condition was the most recommended for the processing of the product., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2019.)

In the present work, the bioaccessibility of the main phenolic compounds of a juçara, banana and strawberry homogenized smoothie (control), subjected to pasteurization and sonication, was evaluated. The smoothie was also evaluated in terms of its main chemical and physical characteristics. Pasteurized smoothie showed higher apparent viscosity, as well as higher initial shear stress when compared to the control and sonicated samples. The increase in the apparent viscosity of the pasteurized smoothie was associated with the smaller particle size of this sample (68 μm). These characteristics conferred to the pasteurized smoothie higher physical stability than the control and sonicated smoothies. Phenolic compounds bioaccessibility was higher in the pasteurized and sonicated smoothies than in the control sample, which confirmed the positive effect of the treatments for the preservation of these compounds after gastrointestinal digestion. Compared to the sonication process, the pasteurization provided higher total phenolic compounds bioaccessibility (47%), as well as of ferulic (16%) and ellagic (80%) acids. Antioxidant capacity was higher in gastric digest for all the samples evaluated by ABTS assay. These results confirm the importance of processing on the physical stability and phenolic compounds bioaccessibility of the juçara-based smoothie, standing out the thermally treated product., (© Association of Food Scientists & Technologists (India) 2019.)