Goat milk is an attractive food because of its nutritional properties, easy digestibility and hypoallergenicity. Goat milk yogurt is an appropriate matrix for the inclusion of new ingredients such as probiotic cultures, fruit and its derivatives. Grapes are rich in polyphenols and recognized for their health benefits. The aim of this study was to improve the quality characteristics of probiotic goat milk yogurt by the addition of an Isabel grape (Vitis labrusca L.) preparation (IGP). For this, the influence of the addition of IGP on the physicochemical, microbiological and sensory characteristics of goat milk yogurt containing the probiotic Lactobacillus acidophilus LA-05 was evaluated during 28 days of refrigerated storage (5 ± 0.5 °C). Four yogurt formulations were prepared, each varying in the added IGP amount, as follows: Y0 (not containing IGP), YG15 (containing 15 g per 100 mL of IGP), YG20 (containing 20 g per 100 mL of IGP), and YG25 (containing 25 g per 100 mL of IGP). All formulations showed probiotic counts ranging from 7 to 8 log CFU mL⁻¹ over the assessed storage period. The addition of 20 g per 100 mL of IGP affected positively the colour, viscosity, and sensory acceptance of the yogurt formulations. The production of goat milk yogurt containing L. acidophilus LA-05 and IGP is an option for developing a new goat dairy product with added value due to the inclusion of components with potential functional properties.

This study evaluated the protective effects of coproducts from agroindustrial processing of the tropical fruits acerola (Malpighia glabra L., ACE), cashew (Anacardium occidentale L., CAS), and guava (Psidium guayaba L., GUA) on the probiotics Lactobacillus paracasei L-10, Lactobacillus casei L-26, and Lactobacillus acidophilus LA-05 during freeze-drying and storage. The occurrence of damage to membrane integrity, membrane potential, and efflux activity of Lactobacillus cells after freeze-drying was evaluated by flow cytometry, and viable counts were measured immediately after freeze-drying and during 90 days of storage under refrigerated or room temperature conditions. Probiotic strains freeze-dried without substrate had the overall highest count reductions (0.5 ± 0.1 to 2.9 ± 0.3 log cycles) after freeze-drying. Probiotics freeze-dried with fruit processing coproducts had small cell subpopulations with damaged efflux activity and membrane potential. Average counts of probiotics freeze-dried with ACE, CAS, or GUA after 90 days of storage under refrigerated or room temperature were in the range of 4.2 ± 0.1 to 5.3 ± 0.2 and 2.6 ± 0.3 to 4.9 ± 0.2 log CFU/g, respectively, which were higher than those observed for strains freeze-dried without substrate. The greatest protective effects on freeze-dried probiotics were overall presented by ACE. These results revealed that ACE, CAS, and GUA can exert protective effects and increase the stability of probiotic lactobacilli during freeze-drying and storage, in addition to supporting a possible added-value destination for these agroindustrial coproducts as vehicles for probiotics and for the development of novel functional foods.

A promising strategy to improve the gut microbiome in hypertension is to target the gut microbiota. This study evaluated the effects of a potential nutraceutical product composed of three strains of Limosilactobacillus (L.) fermentum, quercetin, and resveratrol on the intestinal microbiome of healthy and hypertensive subjects. The nutraceutical product consisting of strains of L. fermentum 139, 263 and 296, fructooligosaccharides (200 mg), quercetin (160 mg), and resveratrol (150 mg) (LfQR) was added to the in vitro fecal fermentation process occurring for 48 h. Fecal samples of healthy and hypertensive subjects were allocated into four groups: (i) healthy controls (CTL); (ii) healthy controls with the addition of LfQR (CTL + LfQR); (iii) hypertensive (HTN) subjects; and (iv) hypertensive subjects with the addition of LfQR (HTN + LfQR). The diversity and composition of the fecal microbiota and the production of microbial metabolites were evaluated. CTL and HTN groups exhibited a distinct gut microbiota composition, as shown by the β-diversity assessment. The addition of the potentially nutraceutical-modulated β-diversity was similar between CTL and HTN groups, suggesting a similar gut microbiome composition after nutraceutical addition. The addition of the nutraceutical product increased the relative abundance of Enterobacteriaceae in the CTL group and that of Lachnospiraceae in the HTN group. The nutraceutical media showed higher levels of sugars (maltose, fructose, and glucose), lactic acid, ethanol, succinic acid, and acetic acid compared to the CTL and HTN media. Although the results are heterogeneous between healthy and hypertensive fermentation media, it was demonstrated that the nutraceutical formulation can modulate the intestinal microbiota and its metabolic activity.