Mango and carrot mixed juice: a new matrix for the vehicle of probiotic lactobacilli.

This study evaluated the pH, acidity, soluble solids, color, dietary fiber, sensory acceptance and the viability of Lactobacillus rhamnosus, Lactobacillus plantarum and Lactobacillus acidophilus in mango and carrot mixed juices. In addition, this study verified the resistance of L. plantarum that presented greater viability to the gastrointestinal tract simulated in vitro. Three formulations were elaborated (varying the pulps concentration) and the products were stored at 8 °C for 35 days. No difference was found in the total soluble solids and color of the products during storage time at 8 °C. A reduction in pH and an increase in acidity were observed in all samples during storage, probably due to the fermentative action of probiotics, which negatively influenced acceptance after 35 days of storage. On the other hand, juices with a higher concentration of mango pulp were more accepted and may be a strategy to improve the acceptance of fermented juices. Microorganisms showed greater viability in juices that had higher amount of carrot pulp, probably due to the higher fiber content in these samples. During the 35-day shelf life, all juices with L. plantarum maintained counts above 7 log CFU mL-1 after gastrointestinal conditions simulation. Therefore, mango and carrot mixed juice showed to be as a good vehicle for probiotic bacteria and meets the needs of consumers looking for functional, healthy, non-dairy and low-sugar foods.

Development of a mixed jussara and mango juice with added Lactobacillus rhamnosus GG submitted to sub-lethal acid and baric stresses.

This study evaluated the interference of sub-lethal acid (SLA) stress and high isostatic pressure (HIP) stress on the survival of Lactobacillus rhamnosus GG (LGG) in mixed jussara and mango juice with the pH adjusted to 3.0 and 3.5, during 90 days of storage at 6 °C. The SLA stress at pH 4.0 previously applied to the LGG cells had no effect on the survival of this bacterium in mixed jussara and mango juices. On the other hand, the application of 200 MPa/5 min/25 °C treatment to LGG cells was shown to be efficient in the cross protection of this bacterium in an acid medium. Pressures above 400 MPa/5 min/25 °C caused a reduction in the viability in an acid medium and lower pressures (< 100 MPa) showed similar results compared to control treatment in the LGG survival. No changes in pH, acidity and soluble solids were observed in mixed juices. In addition, these products showed elevated levels of anthocyanins, phenolic compounds and antioxidant capacity. This highlights the capacity of the HIP process to promote the cross protection of LGG in an acid medium.

Use of gelatin and gum arabic for microencapsulation of probiotic cells from Lactobacillus plantarum by a dual process combining double emulsification followed by complex coacervation.

The objectives of this study were i) to microencapsulate probiotic cells of Lactobacillus plantarum through a dual process consisting of emulsification followed by complex coacervation using gelatin and gum arabic, ii) to characterize the lyophilized microcapsules, iii) to evaluate their behavior in simulated in vitro gastrointestinal conditions and iv) to evaluate the survival of microencapsulated probiotic cells during 45 days of storage at 8 °C, 25 °C and -18 °C. The optimized conditions for complex coacervation consisted of a 50:50 biopolymer ratio and pH = 4.0. Emulsification was followed by complex coacervation using gelatin and gum arabic. The microcapsules presented dispersibility of 0.183 ±â€¯0.17 g·mL-1, moisture content of 4.5%, water activity of 0.34 ±â€¯0.03 and hygroscopicity of 9.20 ±â€¯0.43 g of absorbed water per 100 g. Their size ranged from 66.07 ±â€¯3.04 µm to 105.66 ±â€¯3.24 µm. Viability of the encapsulated L. plantarum cells was 8.6 log CFU·g-1 and the encapsulation efficiency was 97.78%. After in vitro simulation of gastrointestinal conditions, viability of the encapsulated cells was 80.4% whereas it was only 25.0% for the free cells at 37 °C. Probiotic cell viability was maintained during storage at 8 °C and - 18 °C for 45 days.