Orange juice added with L-casei: is there an impact of the probiotic addition methodology on the quality parameters?

The objective of this study was to evaluate the effect of the probiotic addition methodology (direct addition of the lyophilized commercial culture, probiotic activated by propagation, or probiotic encapsulated in alginate, 10(8) CFU/mL) on the physical and chemical characteristics, rheological parameters, volatile compounds profile, probiotic culture survival and sensory acceptance of orange juice during refrigerated storage (7 degrees C/28 days). The direct addition of the commercial culture was the most suitable methodology, resulting in products with physical and chemical characteristics and sensory acceptance similar to those of the pure product. Furthermore, it improved the volatile compounds profile (presence of octanal, nonanal, decanal, gamma-terpinene, alpha-phellandrene, o-cymene, alpha-cubebene and 1-hexanol). The addition of the activated probiotic culture resulted in products with higher content of organic acids (acetic, lactic and citric), absence of important volatile compounds and lower sensorial acceptance. The addition of the encapsulated probiotic culture resulted in more consistent products (higher consistency index and lower flow behavior index), decreased organic acid content and lower sensorial acceptance. This is the first study that evaluated the impact of different probiotic addition methodologies on the quality parameters of fruit juices and it indicated that the conventional methodology (by propagation) is not the most appropriate.