This work reports the survival status of Listeria monocytogenes, Escherichia coli O157:H7, Staphylococcus aureus and Salmonella Typhimurium in homemade fig and mulberry vinegar. Each pathogen was separately inoculated in vinegar samples at approximately 7 log CFU/mL. The survival status of pathogens was examined at 20°C for 0, 15, 30 and 60 min, and 4, 8 and 24 h. The residual populations after 24 h were below detection limit for all species assayed. S. Typhimurium was much more sensitive to mulberry vinegar ( 6 log reduction in 30 min) than it is to fig vinegar ( 6 log reduction in 24 h). L. monocytogenes had an overall quite different behaviour, being the most sensitive species to fig vinegar ( 6 log reduction in 4 h) while being the most resistant one to mulberry vinegar ( 6 log reduction in 24 h). The total phenolic content of fig vinegar (767 mg GAE/L) was higher than mulberry vinegar (557.5 mg GAE/L). The results exhibited that antimicrobial activity of vinegar is mainly related to the contact time, test pathogen and physicochemical properties of vinegar.

This study was carried out to evaluate survival of Bifidobacterium infantis 20088 in fermented beverage formulated from selected traditional Sudanese fruits Gudaim and dom. The viable counts of the strain and physiochemical changes during refrigeration were determined. 10% beverages (w/v) were prepared from dom and gudaim powder. 2.5% (w/w) skim milk was supplemented to each formulation to provide the required nutrient for bacteria growth during the fermentation. After sterilization and cooling, the mixture was inoculated with a 10% culture of B. infants 20088 followed by incubation for 36 h at 37°C. Reconstituted skim milk was used as control. Fermented beverages were held at refrigeration (4°C) for a period of 2 weeks. During the refrigeration storage of the fermented beverages there was significant reduction in Bifidobacterium infantis of all fermented beverages. Nevertheless, the strain was maintained high; fulfill the number required to presence in probiotic foods, which was at least 6 log CFU/ml fermented product. There was no significantly difference in TSS and pH as compared to their initial at the beginning of fermentation except in pH of fermented gudaim. Therefore gudaim and dom are suitable carrier to deliver Bifidobacterium infantis 20088 to consumer.