Wood Magazine this month published a question from a reader asking which woods are food safe. Their reply was that tight-grained domestic hardwoods, especially maple, birch, and beech leave fewer hiding places for food-borne bacteria than open-grained wood. Yet they said parenthetically that Bamboo, which is a grass, was also food safe–though Bamboo has a very open grain and that would seem to contradict their point. They went on to say that lighter colored wood is a better choice than darker colored wood because “the color can leach out when wet” especially if you use highly diluted chlorine bleach to sanitize your boards.
I really like Wood Magazine, and I read it thoroughly each time it comes. I have a great deal of respect for them in general. Still, I have some concerns about this answer because it does not entirely square with studies such as the one linked here. I first read this on Al Ladd’s site , but I have read other sources that talk about the natural anti-microbial properties of certain woods, maple among them.
I’ve made boards from maple, cherry, oak, and walnut. Personally I find oak too porous for my taste, and I would avoid it for all but cheese or vegetable use. I do think that there is something to the idea that more porous woods are a better environment for bacteria. On the other hand, I really don’t worry too much about it in general.
The walnut board we use in the kitchen has never shown any tendency to bleed color (How could it unless it were stained?) and seems to clean up well. Rather than disinfecting with diluted bleach, we generally use water, or water and dish soap, and I always recommend drying boards immediately to prevent cracking. Dishwashers are, of course, completely out of the question for wood boards. Still, we’ve never had an issue with illness or any sort of growth on any of our boards. This is all anecdotal, I realize that, but it’s how we operate with our boards here.
I have noticed that the maple and cherry boards have a much greater tendency to “cure” than the walnut one does. By “cure” I mean that the board takes on a kind of oily or waxy feel and naturally begins to shed water. “Back in the day,” board makers used a mixture of mineral oil and paraffin wax to finish boards and treat them from time to time. I think the curing effect we see is the same basic thing, and I attribute it to the tighter grain of maple and cherry preventing loss of food oils or oils used to treat the boards. When I treat my own boards I use mineral oil, but my daughter has used vegetable oil and her board shows no sign of the oil becoming rancid as I had expected it might. Go figure.
Anyway, I guess my point here is that I think all the concern over which woods are food-safe is overkill. Please read the study for yourself, and draw your own conclusions. I am certainly not an expert in biology, nor am I a doctor or anything remotely connected to those professions. I am simply still living and healthy after showing no concern about my wooden cutting boards.