The effect of an antibacterial washing-up liquid in reducing dishwater aerobic plate counts.
OBJECTIVE
To assess any significant differences in the aerobic plate count (APC) of catering dishwaters following the use of a traditional, nonantibacterial or an antibacterial washing-up liquid.


RESULTS
A dishwashing trial was undertaken within a commercial restaurant of 6 weeks duration (3 weeks with each washing-up liquid in a randomized, weekly pattern). Five replicate samples were taken from the dishwater at the end of the washing-up operation, on three separate occasions each day corresponding to mid-morning, lunchtime and mid-afternoon meal preparations.


CONCLUSIONS
The antibacterial product was shown to significantly reduce the APC by an average log10 reduction of 1.81 CFU ml(-1) (98.5%) as compared with the traditional product. APC were lower for each of the three weekly time periods for the antibacterial product. Continued use of the antibacterial product did not decrease the APC of the dishwater, though with the traditional product, dishwater counts increased throughout the trial week.


CONCLUSIONS
Antibacterial washing-up liquids, with proven activity in controlling levels of microorganisms in dishwaters, could play a significant role in reducing the risk of cross-contamination between washed articles during washing-up operations.
Holah
J T
JT
Department of Food Hygiene, Campden and Chorleywood Food Research Association, Chipping Campden, Gloucestershire, UK. j.holah@campden.co.uk
Hall
K E
KE
D001420:Bacteria, Aerobic / Q000254:growth & development*; D001645:Biguanides; D015169:Colony Count, Microbial; D003297:Cooking and Eating Utensils; D003902:Detergents / Q000737:chemistry; D004202:Disinfectants; D005516:Food Microbiology; D014871:Water Microbiology
D001645:Biguanides; D003902:Detergents; D004202:Disinfectants; C031233:polihexanide