Food Safe Wood for Cutting Boards
Oct 21st, 2007 by Larry
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.
Larry,
A couple of comments. First thank you for making this study available. Like you, I always assumed plastic was better than wood. I still think this is better in that plastic should not absorb anything. But we know woods naturally contain phenolic substances which are antibacterial. And this study supports this.
However, some of the tropical woods like rosewood are oily and will not glue easily due to the exudation of these oils and may explain your results. However, tropical woods are not the best to use as some have been indicated as carcinogenic (http://healthfully.org/eoh/id1.html ) in some cases where the dust was breathed. Unlikely this is a problem for short contact, but I’d stay away from tropical woods no matter how beautiful. Cedar ( esp Western Red) dust has been implicated as being carcinogenic. Dave Burley
Dave,
Your point about exotics is a good one. Woods like Teak, Cocobolo, Ipe, and so on are not the best candidates for use in cutting boards. I tend to be a little “old-school” when it comes to all this, however. By that I mean that I don’t get too bothered about carcinogens or other problems that are only manifested over time. The way I look at it, if you give a rat enough of anything, eventually it causes cancer. — Now I’ll probably get nailed in comments or email for being insensitive and reckless.
Anyway, thanks for dropping by and for adding your excellent insights.
[...] 20.04 | Larry in Food Safe Wood for Cutting Boards [...]
I was happy to find this discussion. I’ve just had some small wooden bowls made by a woodturner so that I can use them to put crackers and cookies in as snacks for my young son (I am getting rid of all plastics and melamine kitchenware). I am planning to finish them with pure tung oil. Then I realized that I had better be sure none of the woods were toxic! This seems to be a different issue than cutting boards, since the surfaces of the wood won’t be pierced with knives. Still, the bowls are made from exotics like cocobolo, ebony, curapay, rosewood and black walnut. Should I be worried?
To the best of my knowledge pure tung oil is non-toxic. Most tung oil finishes have drying agents however, and those are certainly toxic. As I understand it, once the oil has dried completely (those agents have evaporated out) it is no longer toxic and should be safe for food-bearing vessels. I haven’t researched exotic woods. I know that some woods can be an irritant if their dust is breathed during sanding. Even American Black Walnut falls into this category for some people. I’d advise continuing to research this on the Web if you have concerns. Personally I would feel comfortable using any wood you’ve mentioned, though I don’t know anything at all about Curapay. I have never even heard of that species. I’d probably feel more comfortable with that one if I had at least seen it.
Again, please keep in mind that I am not qualified to answer this question personally. I am merely giving my personal opinions.
I asked the manufactor about using tung oil for food dishes. They said do not use it.
Absolutely correct. You don’t want tung oil because it does not fully cure. Honestly, the best solution is the simplest; just stick with mineral oil. There are some food-safe finishes on the market that make a good alternative as well.