When I took a microbiology class, one assignment we did was to quantify and describe the bacteria on cutting boards. I too was surprised when the data from the class indicated what wood was better (although variation was admittedly high).
1234 (if I may be so familiar as to address you like that!
) -- that first link is excellent, and in addition to their own scientific findings, report another good study:
We believe, on the basis of our published and to-be-published research, that food can be prepared safely on wooden cutting surfaces and that plastic cutting surfaces present some disadvantages that had been overlooked until we found them.
In addition to our laboratory research on this subject, we learned after arriving in California in June of 1995 that a case-control study of sporadic salmonellosis had been done in this region and included cutting boards among many risk factors assessed (Kass, P.H., et al., Disease determinants of sporadic salmonellosis in four northern California counties: a case control study of older children and adults. Ann. Epidemiol. 2:683-696, 1992.). The project had been conducted before our work began. It revealed that those using wooden cutting boards in their home kitchens were less than half as likely as average to contract salmonellosis (odds ratio 0.42, 95% confidence interval 0.22-0.81), those using synthetic (plastic or glass) cutting boards were about twice as likely as average to contract salmonellosis (O.R. 1.99, C.I. 1.03-3.85); and the effect of cleaning the board regularly after preparing meat on it was not statistically significant (O.R. 1.20, C.I. 0.54-2.68). We know of no similar research that has been done anywhere, so we regard it as the best epidemiological evidence available to date that wooden cutting boards are not a hazard to human health, but plastic cutting boards may be.I tried to find another study I recall reading, but could not. However, if my memory is correct (don't count on that, so take this with a grain of salt!),
the wooden cutting boards that were best were those made from woods with high tannin contents like northern red oak Quercus rubra -- these compounds evidently helping to kill the bacteria.
John
