Valutazione della qualità microbiologica delle bevande calde erogate da distributori automatici presenti presso i reparti della Brigata Meccanizzata “Aosta” siti in Messina.

The aim of the present study was to evaluate the microbiological quality of hot beverages dispensed by vending machines (VM). The study was carried out on 203 samples from 15 VM located in 5 army barracks in Messina. The samples included: water used for preparation of beverages, “water swab”, “blender swab”, chocolate and milk powder, cappuccino and chocolate drink (29 samples for each types). All samples were examined for total bacterial count (TBC), coliforms, Escherichia coli, enterococci, Pseudomonas aeruginosa, Staphylococcus aureus, Clostridium perfrigens, Aeromonas spp., Salmonella spp. and Listeria monocytogenes. For the water samples the colony count (CC) at 22°C and at 37°C was made. The average values of CC at 22°C and at 37°C were of 10.86 x 102 ± 8.72 x 102 CFU/ml and of 21.72 ± 16.44 x 102 x 102 CFU/ml respectively. The TBC ranged from 176 CFU/g (± 275.2) for chocolate powder to 294.8 ± 69.4 CFU/g for milk powder. P. aeruginosa, coliform bacteria, S. aureus, E. coli and molds were detected from water. S. aureus and molds were isolated from milk powder, while coliforms, E. coli and S. aureus were observed in chocolate powder. The average TBC for hot beverages ranged from 34.32 x103 ± 97.77 x103 CFU/ml for cappuccino to 36.59 x103 ± 10.47 x104 CFU/ml for chocolate drink. Coliforms, E. coli, enterococci and molds were detected from cappuccino, while enterococci and molds were observed in chocolate drink. The microbiological characteristics of the water and powders and hygiene and the periodic cleaning of machines, influenced the microbiological quality of the hot beverages dispensed by VM.