No abstract

The presence of antibiotic residues in drinking water may be a source of contamination, which could affect the diffusion of polyphenols into the wine must during the traditional fermentation process. Antibiotic residues such as ivermectin, hydroxychloroquine, ciprofloxacin, and azithromycin on the diffusion of polyphenols and anthocyanins during wine fermentation were studied. Different samples were taken at different periods (0, 48, 96, and 168 h) to analyse the total polyphenols, anthocyanin content, and antioxidant capacity, which were correlated with Peleg’s equation to establish the diffusion kinetics of these compounds. The results indicated that the presence of antibiotics reduced between 40 and 50% the diffusion of the total polyphenols and monomeric anthocyanins in red wine. The use of ivermectin showed the highest kinetic parameter k1 compared with the use of other antibiotics. This suggested that the chemical structure and molecular weight of the antibiotics could play an important role in inhibiting the metabolism of yeasts affecting the ethanol and CO2 production. Consequently, cell membranes would be impermeable and would not allow the release of polyphenols and anthocyanins. Therefore, it is necessary to establish strategies that allow future water quality control in wine production companies.

La ultra-alta presión de homogenización (UHPH) es una tecnología emergente con aplicaciones en el procesamiento de fluidos. Si bien, esta tecnología se basa en los mismos principios de los homogeneizadores convencionales, los nuevos diseños y uso de materiales de construcción de las válvulas han permitido alcanzar presiones de 350 a 400 MPa. Las ventajas de la UHPH incluyen la reducción del tamaño de partícula, incremento de la vida útil mediante de la inactivación de microorganismos y mejoras en la funcionalidad debido al aumento de la capacidad y estabilidad de la emulsión, con efectos mínimos sobre el valor nutricional y las características sensoriales. Asimismo, los efectos térmicos son menores debido al tiempo de tratamiento (menos de un segundo). La tecnología UHPH es un proceso sostenible que tiene una aplicación potencial en las industrias cosmética, farmacéutica y láctea. En la presente revisión se muestra una visión general de algunos estudios recientes de la aplicación de la tecnología UHPH en el tratamiento de la leche y en la fabricación de quesos.

Firstly, this study aimed to determine the effect of adding nisin (0, 250 and 500 IU mL-1) and oregano essential oil (OEO) (0, 0.025% and 0.05%), alone or in combination, on Staphylococcus aureus load in cow’s milk. Next, it was evaluated the sensory, physicochemical and microbiological quality of fresh cheese (FC) manufactured with milk added of nisin + OEO (C1) or nisin alone (C2) compared to a control cheese (C0, milk without the addition of nisin or OEO). Results showed that adding nisin effectively reduced the S. aureus count in milk in a similar manner to adding way the combination of nisin + OEO compared to the control. FC quality evaluation results revealed that C1 and C2 did not alter the physicochemical quality of FC (pH, fat and total solids content) during storage (0-8 days) compared to the control. Furthermore, C1 and C2 reduced in a similar manner aerobic mesophilic bacteria and Enterobacteriaceae count in FC compared to the control during storage. Sensory evaluation showed that consumers did not value FC added of nisin + OEO (C1) due to its intense aroma of oregano, rating it with the lowest global quality.