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.

Increased thermal stability of anthocyanins at pH 4.0 by guar gum in aqueous dispersions and in double emulsions W/O/W.

This study investigated the potential of guar gum and a double emulsion to increase the thermal stability of anthocyanins. The effect of different guar gum concentrations (0%, 0.25%, 0.50%, 0.75%, 1%, 1.25%, 1.5% and 1.75%) was evaluated in relation to color stability, concentration of anthocyanins and antioxidant capacity under storage for 10 days at 40 °C in the presence of light. The addition of guar gum (0.75-1.75%) significantly increased the color stability and bathochromic displacement of the samples, suggesting the occurrence of a co-pigmentation process. The total anthocyanin content was to 41% after storage in treatments without guar gum, but when using 1.25% guar gum the final concentration was 70% and there was a 2.4 fold increase in the half-life time of anthocyanins. A significant effect of guar gum addition on the antioxidant capacity of the samples was observed. In the second step, the anthocyanins were added together with 1.25% guar gum in the internal aqueous phase of the double emulsion and stored for 10 days at 40 °C in the presence of light. The double emulsion presented high encapsulation efficiency (90.6%) and high kinetic stability under the conditions evaluated, in addition to protecting anthocyanin molecules against degradation.