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Cranberry (Vaccinium macrocarpon) is a distinctive source of polyphenols as flavonoids and phenolic acids that has been described to display beneficial effects against urinary tract infections (UTIs), the second most common type of infections worldwide. UTIs can lead to significant morbidity, especially in healthy females due to high rates of recurrence and antibiotic resistance. Strategies and therapeutic alternatives to antibiotics for prophylaxis and treatment against UTIs are continuously being sought after. Different to cranberry, which have been widely recommended in traditional medicine for UTIs prophylaxis, probiotics have emerged as a new alternative to the use of antibiotics against these infections and are the subject of new research in this area. Besides uropathogenic Escherichia coli (UPEC), the most common bacteria causing uncomplicated UTIs, other etiological agents, such as Klebsiellapneumoniae or Gram-positive bacteria of Enterococcus and Staphylococcus genera, seem to be more widespread than previously appreciated. Considerable current effort is also devoted to the still-unraveled mechanisms that are behind the UTI-protective effects of cranberry, probiotics and their new combined formulations. All these current topics in the understanding of the protective effects of cranberry against UTIs are reviewed in this paper. Further progresses expected in the coming years in these fields are also discussed.

The major function of lactic starter cultures in cheese making is to produce lactic and other organic acids from the carbohydrates present in milk. The activity of six starter cultures consisting of two Lactococcus lactis ssp. lactis, two Lactococcus lactis ssp. lactis biovar. diacetylactis and two Leuconostoc strains, was tested by monitoring the evolution of the organic acid composition of milk by a modified HPLC method. In addition, their performance as cheese starters was also tested. The HPLC method developed proved to be a precise tool to monitor the organic acid content. Thus, it can be used to follow the fermentation ability of starter cultures, providing information about the type of fermentation. The use of any of the six starters assayed is suggested for manufacturing Afuega'l Pitu cheese.

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Several benefits have been described for red wine polyphenols and probiotic strains in the promotion of colonic metabolism and health. On the contrary, knowledge about their role in the management of oral health is still scarce. In this work, the antiadhesive capacity of selected red wine polyphenols and oenological extracts against the oral pathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans in an in vitro model of human gingival fibroblasts has been explored as well as their complementary action with the candidate oral probiotic Streptococcus dentisani. Results highlighted the antiadhesive capacity of caffeic and p-coumaric acids as well as grape seed and red wine oenological extracts. Both, caffeic and p-coumaric acids increased their inhibition potential against S. mutans adhesion when combined with S. dentisani. Additionally, UHPLC-MS/MS analysis demonstrated the oral metabolism of wine phenolics due to both, cellular and bacterial activity.

Findings concerning the antiadhesive activity of cranberry phenolic compounds and their microbial-derived metabolites against Gram-negative (Escherichia coli ATCC 53503 and DSM 10791) and Gram-positive (Enterococcus faecalis 04-1) bacteria in T24 cells are reported. A-Type procyanidins (A2 and cinnamtannin B-1) exhibited antiadhesive activity (at concentrations ≥250 μM), a feature that was not observed for B-type procyanidins (B2). The metabolites hippuric acid and α-hydroxyhippuric acid also showed effective results at concentrations ≥250 μM. With regard to conjugated metabolites, sulfation seemed to increase the antiadhesive activity of cranberry-derived metabolites as 3-(3,4-dihydroxyphenyl)­propionic acid 3-O-sulfate presented active results, unlike its corresponding nonsulfated form. In contrast, methylation decreased antiadhesive activity as 3,4-dihydroxyphenylacetic acid was found to be active but not its corresponding methylated form (4-hydroxy-3-methoxyphenylacetic acid). As a whole, this work sustains the antiadhesive activity of cranberry-derived metabolites as one of the mechanisms involved in the beneficial effects of cranberries against urinary tract infections.

Carbon dioxide treatment of refrigerated raw milk was evaluated as a method for extending storage life by inhibiting growth of psychrotrophic bacteria and other bacterial groups in raw milk. The effect of CO2 acidification followed by degasification and pasteurization on biochemical and microbiological properties of cold stored milk was studied on a pilot scale, Two CO2 treatments (acidification to pH 6.2 and to pH 6.0) were compared with a control (untreated) milk during 4 days of storage at 4°C. Total bacterial counts in the categories of milk established in this study were mainly determined by the proteolytic psychrotroph levels. The inhibitory capability of CO2 was greater in the low-quality than in the high-quality milk category. Acidification at pH 6.0 was more inhibitory than that at pH 6.2, especially against proteolytic psychrotrophs. Neither caseins nor whey proteins were affected by CO2 treatment and pasteurization. Organic acid (orotic, citric, uric, formic, acetic, propionic, and hippuric) concentrations did not change after CO2 treatment, cold storage, or the pasteurization process; the lactic acid content of CO2-treated milks remained constant during the refrigeration time but increased slightly in the control. In general, lower amounts of volatile compounds were produced in CO2-treated milks during refrigeration than in control milk. Ethanol and 2-propanol levels were most affected by degasification and pasteurization. Sensory evaluation revealed no significant differences between CO2-treated milk after degasification and pasteurization and the untreated milk used as control. It was concluded that degasification and pasteurization on a pilot scale eliminated CO2 from milk with minimum detrimental effects on its biochemical and sensory properties, making this process acceptable for milk preservation.