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Introduction. Wood infection and disinfection are significant challenges that are linked with public health as well as food safety, since wood surfaces are often used as cutting boards or benches (e.g. at home or at the butcher's). The porous and nutritive nature of wood is ideal for accumulating microorganisms that can contaminate food, while the use of strong chemicals like chlorine, condensed acids or alkali is not appropriate for such surfaces, as they can damage wood or transfer toxic substances onto food. Thus, more natural methods for disinfecting wood are necessary. Moreover, the type of wood and the cutting method may affect both the porosity of wood and the effectiveness of disinfecting methods. Materials and methods. Three types of wood (chestnut, beech and fir tree wood) and two types of wood cutting method (tangential and axial cutting) were used as meat cutting boards and we submitted for comparison regarding their resistance against contamination and the efficacy of disinfection. Also, six different methods of wood disinfection were applied separately (control method without disinfection, disinfection with the addition of salt, baking soda, vinegar, steam and pre-treatment of wood with ZnO for self-disinfection) and their decontamination efficacy was compared with meat spoilage bacteria naturally present in freshly minced meat (Total Plate Count, Enterobacteriaceae), or pathogenic bacteria (Campylobacter, Salmonella, Escherichia coli, Staphylococcus aureus, Clostridium perfringens) that were inoculated in the minced meat before coming to contact with the wood surface. Results and conclusions. The results indicated that chestnut was the type of wood that was most resistant to contamination after coming to contact with fresh meat, probably due to the presence of antimicrobial tannins which occurs there and it is a less porous surface, compared to other types of wood, second best results were achieved by fir wood. The beech, which is apparently the most common tree used for this type of industrial application, including at the butcher's (as meat cutting boards), was in fact the least resistant to bacterial contaminations and so the least suitable to be used. The tangential cutting was generally preferable to axial cutting, probably due to the leaner and less porous surface that it produces, which is easier to clean, wash and disinfect. The addition of vinegar was the optimal method for wood surface disinfection (after the contact with meat), regardless of the type of wood or the cutting method. ZnO was also quite effective against most of the tested bacteria. The efficacy of ZnO (which was embedded into wood) was better for the axial cutting method, which resulted in a more porous and absorbent surface, that can better absorb the ZnO solution. We can conclude that the use of vinegar can effectively disinfect wooden surfaces, and while the self-disinfection property is desirable, the application of ZnO is the most preferable method. [ABSTRACT FROM AUTHOR]

The aim of the present work was to investigate the potential prebiotic action of Goji berry powder on selected probiotic bacteria grown in a nutritive synthetic substrate and in simulated gastric and intestinal juices. Different probiotic strains of Bifidobacterium and Lactobacillus were grown in these substrates with or without the addition of encapsulated goji berry extracts of different polysaccharide and polyphenol contents. The results proved that the addition of the extracts promoted the proliferation of probiotic strains and, in particular, increased the number of bacterial colonies of Bifidobacterium animalis subsp. lactis (Bb12), Bifidobacterium longum (Bb46), and Lactobacillus casei by 2, 0.26, and 1.34 (log cfu/mL), respectively. Furthermore, the prebiotic effect seems to be correlated to Goji berry polysaccharides and/or polyphenols, higher contents of which (under the tested concentrations) could increase the stress tolerance of B. lactis and B. longum in a simulated gastrointestinal environment. According to the findings of the present research, it can be suggested that the Goji berry encapsulated extracts could be used as prebiotic additives in food or nutraceuticals, in order to stimulate growth or protect the viability of probiotic strains of Bifidobacterium and Lactobacillus. [ABSTRACT FROM AUTHOR]