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.
I have a local connection to coco bolo. I would like to make solid one piece natural edge cutting boards.What are the pros and cons to using coco bolo and will they warp if there one solid piece.
Cocobolo is a wonderful wood and very beautiful. It is relatively dense and finishes to a wonderful shine with fine abrasives such as 0000 steel wool. Cocobolo is similar to teak in some respects and tends to be a little oily. Exposed to the open air for a time it does dry to the point where its initial oily nature is no longer an issue. As it dries, the wonderful red/orange color you first see when machining it darkens and becomes more brown; so be prepared for some color change over time. In general, I have found Cocobolo quite stable. I once made a lazy-susan from a piece that I had re-sawed a quarter-inch thick, and it stayed flat. Cocobolo is considered an exotic, and it isn’t one I have used for cutting boards. I do have a kind of spatula made from Cocobolo. This implement is designed to be used in contact with food and was carved by a craftsman in Nova Scotia Canada. Other than this empirical evidence I do not know if it is food-safe. Being who I am, I’d use it anyway. But that’s me. ;-) So I’d say that Cocobolo should make a beautiful cutting board, and the idea of leaving a natural edge should make it a very interesting conversation piece of which you can be proud.
Great discussion! Here’s a question for you guys:
I’m in NYC and as a sustainable furniture designer I often use reclaimed planks of yellow pine (and douglas fir) that came from demolished buildings. The yellow pine has a very high resin content and is dense as heck! I currently have a ton of off-cut around the shop so I was thinking about making some cutting boards. Does anybody know if yellow pine is food safe?
Thanks,
Dan
Welcome, Dan!
I don’t know if it is food-safe or not, but as long as it’s not sticky, I’d personally give it a shot. If I got a flavor in the food I’d quit. heheheh They serve Tilapia fillets on Cedar at the Chilli’s Restaurant near me, and I wouldn’t think of making a cutting board out of that. Southern Yellow Pine is some amazing wood. Very dense, as you say, and just basically wonderful to work with.
I’m going to start making cutting boards as well. What do you know about Oak, Pecan or Hickory?
Thanks for dropping by, Rudy.
We don’t see much Pecan here in NY, and Hickory is relatively rare as well, so I have never used either of them at all. I am completely unfamiliar with the properties of Pecan. Hickory is very hard, and I think it would be a good choice.
Now that you mention it, I may try to find some for myself. It sounds like fun.
I have made Oak cutting boards, but I personally do not favor Oak because it is very open-grained. That gives it a tendency to retain particles and get dirty easily. The open grain also makes it absorb liquids rapidly and Oak is therefore somewhat more subject to movement. That said, Walnut is an open-grained wood and I use that all the time. So; Oak works, but I prefer it for cheese or vegetable boards rather than serious chopping blocks to be used with meats.
My father is thinking of making a wooden honey pot out of ash wood (we had some trees lopped last year so we have some wood left over.) . Does anyone know if ash is safe?
V
I can’t tell you definitively, but I personally would not hesitate to use it. Ash is what they use to make baseball bats. It’s quite hard and not sappy. I’d want to be sure I was using a well dried piece, since it may have a strong tendency to move after machining if it isn’t dry. I’d say you have an extra benefit if the vassel is to be used for honey. Honey does not spoil. It’s naturally antibacterial. So, like I said, I can’t tell you for a fact that Ash is OK (my lawyers would have coronary) but I personally would not think twice about it. I’d personally eat off Ash without concern.
great discussion, I am thinking of using heartwood (so. yellowpine) to make some butcher blocks as well as countertop. Any thoughts on this one? As far as plastics go, I would be more concerned on what they excrete than what they absorb. I have read a lot of articles on plastic. basically one in a bazillion reasons to avoid plastic is as follows in this article regarding plastic in the ocean. “Plastic pellets have been found to accumulate up to one million times the level of these poisons that are floating in the water itself. These are not like heavy metal poisons which affect the animal that ingests them directly. Rather, they are what might be called “second generation “ toxics. Animals have evolved receptors for elaborate organic molecules called hormones, which regulate brain activity and reproduction. Hormone receptors cannot distinguish these toxics from the natural estrogenic hormone, estradiol, and when the pollutants dock at these receptors instead of the natural hormone, they have been shown to have a number of negative effects in everything from birds and fish to humans. The whole issue of hormone disruption is becoming one of, if not the biggest environmental issue of the 21st Century. Hormone disruption has been implicated in lower sperm counts and higher ratios of females to males in both humans and animals. Unchecked, this trend is a dead end for any species.”
When you use plastics for cutting boards, the knife cuts into the substrate, creating a gap. Whatever your are cutting enters the gap. If you have an old plastic cutting board, grab the 2 long ends, and flex or bend it. You will see the juices of all that chicken and whatever oozing out.
When you wash a plastic cutting board, you should hold it under a sink full of water and a capfull of bleach – then flex the board so the bleach can clean the cuts.
The 3 cuting board woods that are recommended by chefs are maple, beach, and birch – because they do not leave a taste in the prepared food. People are often nervous about eating from a bowl or cutting board made of Black Walnut (and sometimes cherry) because they believe it is toxic. The Walnut tree is toxic to some plants around it, and the sawdust is not safe for horses, but the wood itself poses no risk for food safety. Other than splinters.
I use maple, birch, beach, walnut, and cherry in my cutting boards. They are preserved with extra virgin olive oil – which does not go rancid. They are cleaned with salt and water, and more olive oil wiped on as needed. This is the easiest, safest, and fastest way I have found for a customer to maintain their boards.
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Thank you for the article. I wanted to point out to Dave that not all plastics are “waterproof” (my words). But we don’t want to assume “plastic should not absorb anything”. Having worked with plastics, I know that some are hygroscopic (yep, not hydroscopic), that is they absorb water. I am not saying it is better or worse than wood, just a note that plastics can be greatly effected by chemicals (chlorine bleach) that would cause eventual degradation. It depends a lot on the type of plastic used. Honestly, I don’t know if a hygroscopic plastic would increase bacteria or reduce it. Certain countries though are willing to use inferior plastics in making products. This makes me wonder what we are consuming. In the end I am sure everything will kill us. So I am going to “biggie size” my fries, with my double stack, and 2 liters of pop.
How can you recommend Mineral oil but not tung oil? Mineral oil is a by product of petroleum refining and it does not fully cure either? There are companies that make polymerized tung oil that will fully cure. Sutherland Welles is one of them.
Mark, thanks for dropping by. This is a great question. Mineral oil is sold in drugstores everywhere for internal use. It has been shown to be completely safe even though it does not fully cure. In addition it is the traditional butcher-block finish, though traditionally it’s combined with wax to give additional durability and aid cleaning. I personally skip the wax; mostly because I am lazy.
However, everything I’ve read makes it clear that all oils that cure fully are food-safe once cured. So Tung oil, which doesn’t fully cure, isn’t a safe choice, but variants that do fully cure would be fine. Polymerized oils have a drying agent, and in some cases they build up like varnish. That wouldn’t be a good choice for a cutting board. Years ago some of the drying agents were dangerous, and this is where many get the idea that some fully-curing oils are not food-safe.
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.
I asked the manufactor about using tung oil for food dishes. They said do not use it.
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 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?
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.
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