Are wooden chopping board hygienic?

Paul Fookes raised an interesting topic on another thread (about my zero waste shop here) but I think the topic stands alone so have started a new thread including the answers to this part of Paul's post:

Paul Fookes Now we have "Health Officials" who are completely risk adverse ....... so we have to have everything over processed and over wrapped.  Our local butcher is always arguing with local health inspector.  He is a 4th generation butcher and uses an apple gum butchers' block.  Eucalypt species have a bacteriostatic oil in the wood so his block is always clean.  We have lost the art of reuse and minimising waste.  ........  Health Officials need more education on natural bacteriostatic solutions available and the downside of ingesting plastic slivers that become lodged in the gut.

As Paul states, many wood species are known to be antiseptic, although others are toxic. I have a wooden chopping board that I inherited from my gran, I think it may be elm. I think of her every time I use it. It's worn and shabby, probably at least 50 years old but I love it - a good scrub under hot water and I believe it'll do another 50 years.

Paul Fookes wrote:Eucalypt species have a bacteriostatic oil in the wood so his block is always clean.

I think our local environmental health may be up to speed on this one.  I went on a food packaging and labelling course a few years ago now, and butcher's blocks were discussed, and they said that wooden blocks can be perfectly fine.  I guess what they are made from would make a difference, but they certainly don't have to be plastic!

A study by the University of Wisconsin found that bacteria on wood cutting boards die in three minutes. Wood cutting boards are in fact safer than plastic ones. My understanding is that the wood absorbs the water which the bacteria needs to live. So the bacteria just dries up and dies.

https://butcherblock.com/wp-content/uploads/2012/09/University_of_Wisconsin_Simple_Version-1.pdf

I think if my memory serves me they banned all wood in commercial kitchens in the UK due to germ fears, but then it was disproved and you are allowed to use it again. I may be miss remembering however.

Skandi Rogers wrote:I think if my memory serves me they banned all wood in commercial kitchens in the UK due to germ fears, but then it was disproved and you are allowed to use it again. I may be miss remembering however.

There was a huge push to introduce the coloured polypropylene boards across the world and these have, for some people had a serious health issue.  Small "darts" are shaved off by the knife and swallowed while eating the food prepared on the board.  They embed in the gut wall and create an inflammatory reaction which in the longer term has been shown to be a trigger for cancer and other diseases.  The other issue for these boards is that the cuts are difficult to clean out so can be a harbour for bugs and grime.  The other issue is that the darts become part of the micro-plastic environmental pollution.
This a balanced view about both types of boards: https://news.ncsu.edu/2014/09/cutting-boards-food-safety/
We have been using hardwood or bamboo boards for over 40 years and have never had a problem.  They get washed in hot soapy water and air dried.  For my money, when they are too old, they can become firewood or put into the garden.

I have utilized and preferred wood cutting boards for my thirty two years of life but have not had a scientific basis behind the decision before aesthetics.

I have heard of properties regarding to all sort of different materials for cutting boards but I think, to reduce risk, 'proper' handling of foodstuffs can remove fears. I try to separate different surfaces for either veggie/fruit or meat cutting. I intentionally try and avoid any chance of cross contamination and then make sure to thoroughly clean my cutting services after I have finished my task. I have been fortunate enough to have not had food poisoning so I continue with this practice.

A lot of my cutting boards have been made of bamboo and are showing their age. I have been transitioning to hardwood solid one piece boards but they tend to have a higher cost. I'm tempted to just buy some hardwood lumber and try to make my own boards here in the near future.

I have a HM maple cutting board counter to the left of my stove. We have a small maple cutting board and a HM (not by us, I bought it used) flat piece of stainless that doesn't work well. (I should get rid of it, but haven't.) And, new to us, we have the butcher block table we just got at auction that's split into 2 large chunks.

I got rid of all the plastic but the chunk of corian my partner uses to roll out biscuits, pizza dough, etc. He's talking about replacing the corian with some of the butcher block. (I hope!)

There's a series of ads that talk about microplastic chips getting in your food and how dangerous it is. I agree with the idea of the microplastics. But they also say that wood is inherently dangerous because it's porous and holds bacteria? We clean our teeth with toothpicks (wood, mostly) and human have eaten off of wood for centuries. I think that saying wood is more dangerous just because it's porous is more of the "too clean for our own good" ideas popular now. And, of course, the ads I'm seeing? They're for metal cutting boards. Given a choice? I'd rather "eat" wood than plastic or metal, thanks.

I don't want metal. I'm old. I don't want anything that's heavier than it has to be! And, I don't see any reason to buy something else. If I'm worried about cross-contamination between raw chicken and veggies say? I cut the chicken on a ceramic plate and leave it there until I'm ready to cook it.

Timothy Norton wrote:I have utilized and preferred wood cutting boards for my thirty two years of life but have not had a scientific basis behind the decision before aesthetics.

here you are Timothy, there is a scientific basis supporting your decision😉


https://pubmed.ncbi.nlm.nih.gov/31113021/

https://www.mdpi.com/2079-6412/13/4/752

Our local health authority suggests wooden cutting boards are the most safe for the home environment.  Provided they are oiled regularly (twice a year depending on use).  Washed immediately with (in order of preference) water, water and salt, or water and soap.  Allowed to dry completely.  

Drying completely between use is emphasized. Bacteria needs moisture to multiply.

A separate cutting board for raw meat that is bleached (hydrogen peroxide preferred).  

For industrial food processing, the requirements are different as everything needs to be steamed or chlorine bleached.  There are exceptions for meat processing which is usually done on a wooden butchers block as that has far less chance of growing invisible beasties when managed correctly.

Plastic cutting boards are no longer recommended for the home unless single use as they can increase microplastic food contamination and are difficult to clean completely as bacteria can hide in the micro cuts and since they don't dry as fast in the cracks, the bacteria can replicate.

Most important is the board must be softer than the knife or risk eating bits of knife which, according to a friend, is not fun.  

My parents used wooden cutting boards for most things (except perhaps meat) and survived well into their 80's. So wood boards must be reasonably hygienic if properly handled.

I think I'll move back to wood for most uses, though I'll keep some plastic for raw meat jobs (easier to sterilize or run through the dishwasher).

Bonus: wooden boards are the best for keeping your knives sharp. Plastic less so. Glass and metal would destroy edges in  no time.

r ranson wrote:Our local health authority suggests wooden cutting boards are the most safe for the home environment.  Provided they are oiled regularly (twice a year depending on use).  Washed immediately with (in order of preference) water, water and salt, or water and soap.  Allowed to dry completely.  

Hello, this came across my mind before, so this is interesting.
What oil would be good for wood cutting boards? I'm thinking something like olive oil?
Also, does water and salt mean salt dissolved in water? How long would the shelf-life be for that you think, before a new salty water mixture is made?

I'll use olive in a pinch.  

Foodsafe flax/linseed and walnut are recommended. Foodsafe mineral oil is also on the list but I hear whispers it will be taken off soon.

Cutting oily foods like sundry tomato in olive oil seems to go a long way to keep the bord from getting dry.

Regarding the use of salt to clean cutting boards, r_ranson made some helpful comments in this thread:

https://permies.com/t/284765

I use walnut oil for our cutting boards, but I don't perfectly remember why. Maybe it's a drying oil like flax/linseed but something we have on hand for salad dressing. And I think olive oil would be prone to rancidity and make the cutting board yucky, at least that's my worry.

Christopher Weeks wrote:I use walnut oil for our cutting boards, but I don't perfectly remember why?

I really like walnut oil for cutting boards. It soaks into the fibers and, if my understanding is correct, it hardens over time.

I use Clapham's salad bowl finish on my cutting boards. I already had it, so I'm using it up. After that, I will probably use Bumbleshoot's wood conditioner, as we bought a bunch of it on sale.

Both are completely food safe and only use materials you can eat.

We live in a log home, with wood floors, and mostly wood counters downstairs, so there's a LOT of wood here to treat. I'm scent/solvent sensitive, so for a long time I've wanted things to use on wood that don't make me sneeze, give me a headache, etc.

I wonder about beeswax to preserve / waterproof wood. Thoughts?

Douglas Alpenstock wrote:I wonder about beeswax to preserve / waterproof wood. Thoughts?

the cutting board and wooden chopsticks are on my list of tasks for this week, and I am using mineral oil followed by a beeswax-carnauba blend. it works really well. beeswax on its own i think needs to be mixed with something softer to make it workable.

I have been making end grain cutting boards for friends and family for years. I did a fair amount of research before starting. What I learned from woodworking forums is that what helps make wood "food safe" is the moisture content. Or lack moisture content.  The lack of moisture makes it difficult for bacteria to grow.  My cutting boards start at about 6 to 10 percent moisture content when I build them.
The best oil is a matter of choice, but a few rules I picked up are to avoid oils that can go rancid and avoid oils that harden. Going rancid is self explanatory.  If the oil hardens then It can only sink into the surface of the wood. Every application of oil after that is on the surface building up a thicker layer. Once you cut that hardened film layer the seal is broken.

My preferred method for finishing a new board is to flood the board with food grade mineral oil repeatedly. letting the oil soak in for a few hours. I repeat this process at least 5 times. The next step is to melt beeswax into some mineral oil. My recipe is 3 parts oil to 1 part beeswax. This is just approximant, I'm aiming for a paste consistency.  Maybe a little thinner than chapstick. I add a few drops of peppermint essential oil but that's just to jazz it up a bit because I give a small jar with the board as part of the gift.  The wax probably isn't necessary but it does greatly increase the time between applications. Put on a generous coat rubbing it into the grain. The paste is thin enough that rubbing it in will melt the wax allowing it to really flood and fill any small cuts or pores in the wood. Let it sit for about an hour and the oil will soak in while the wax hardens. a quick buff and you're done.   My gift boards get 3 or 4 more coats of the mix followed by a buffing with a power buffer. With some work I can get them looking glossy, probably overkill because I have been told more than once that the idea of taking a knife to it seems a shame.

Douglas Alpenstock wrote:I wonder about beeswax to preserve / waterproof wood. Thoughts?

If you heat it before applying it can work ish.  I find it wears off quickly and doesn't have the same germ killing qualities as oil.  If applied too strong, it can create a situation that traps water - the opposite of what we want.

Most commercial wax have a solvent to help it get deep into the wood.  Some products heat a bit of beeswax with linseed oil to get the best of both worlds.  An finish thaf applies like oil but can be buffed.  Great for selling cutting boards.  

So, I gather lemon, salt, heat/sunlight maybe vinegar could be sufficient for sterilizing a wood cutting board, but is oil/beeswax really necessary, or is that just for preservation/aesthetic purposes? Say particularly if you're keeping the board dry with heat between uses?

Oil has three tasks in keeping wood cutting bords safe.

1. Persevering and strengthening the wood so it lasts longer.
2. Fills microscopic voids in the wood so water won't get there and it can dry faster and reduce the chance of bacteria survival.
3. Oil also prevents most bacteria and invisible beasties.  It's a traditional preservative for many foods.  

Our local health authority recommends oiling twice a year is sufficient

r ranson nailed it. The key is keeping the board oiled and allowing it to air dry after use.

Just my opinion based on decades of owning a butcher block cutting board and a butcher block countertop. I see no need for salt, or even worse a commercial detergent for daily use. Both of those will just strip off the wax and oil.
I just use a damp towel to wipe up after vegetables or bread. If something gets overlooked and it gets crusty I might use some vinegar. But very rarely. If I cut meat on it I set it on an angle in the sink to run hot water over it while giving it a quick scrub with a scrub pad. Then let it air dry.

I really haven't given the process this much thought in decades ;)  never had any problems.

Something we discussed a while ago on Permies was the idea of filling our kitchen surfaces with helpful bacteria, that way the niche for bacteria is then filled and the bad ones can’t gain a foothold. Having lots of fermented food around the house, and using edible cleaners seem to help.

As an extra precaution I use chopping boards that have two distinct sides, and use one side for cooked things and the other side for raw meat.

Serge Arni wrote:

r ranson wrote:Our local health authority suggests wooden cutting boards are the most safe for the home environment.  Provided they are oiled regularly (twice a year depending on use).  Washed immediately with (in order of preference) water, water and salt, or water and soap.  Allowed to dry completely.  

Hello, this came across my mind before, so this is interesting.
What oil would be good for wood cutting boards? I'm thinking something like olive oil?

The place I bought my wood chopping boards from use grapeseed oil. Another chopping board maker I knew was using the kind of linseed oil that comes in small bottles for salad dressings etc. So far I’ve only used orange oil, because I had some around for another project, and my husband is allergic to nuts, seeds, and a bunch of other stuff, so I’ve been hesitant to use anything that he can’t eat on the boards. I’d be interested to hear if anyone has any experience with nut allergies and using nut oils on boards.

Kate Downham wrote:Something we discussed a while ago on Permies was the idea of filling our kitchen surfaces with helpful bacteria, that way the niche for bacteria is then filled and the bad ones can’t gain a foothold.

That’s great! We use competitive exclusion in our ferments, and in garden soil, so why not on kitchen surfaces?!

I really like this Wood Oyl for butcher blocks, cutting boards and wooden utensils:
https://www.kramerize.com/products.htm

The other Kramer wood products are fantastic, as well! This is a small company and it feels good to support them.

Gary Crocker wrote:I really like this Wood Oyl for butcher blocks, cutting boards and wooden utensils:
https://www.kramerize.com/products.htm
The other Kramer wood products are fantastic, as well! This is a small company and it feels good to support them.

Thanks for posting that Gary. I'll pass on the word in our CNC meeting coming up this week. Some of the guys are making cutting boards all the time, usually using end grain or inlays as decorative motifs.
There are many solutions and oils people use on their boards. You just have to be careful that those are not detrimental to humans. Beeswax is a good one, especially if you melt it before applying as that gets into the grain better.

Thanks, again

No experience with refinishing but my wooden cutting boards and wooden knife handles are in very sad shape.  For several weeks now, I have been thinking of trying to help them both for both hygienic and esthetic reasons so I have done a slight amount of research.  This is one of the more reasonable sites I visited https://www.lumberjocks.com/threads/cure-time-for-a-pure-tung-oil-touch-up.355787/  
What I know from previous research on paints is that tung oil is heated to almost the fully polymerized stage so that when you apply it, the oil will react with oxygen and fully polymerize, ie, harden, cure.  A finish is intended to soak into the wood grain and a paint is intended to remain on the surface.  Both are expected to cure so they don't transfer to your hands when touched.  
Therefore, it would seem reasonable that any applications to cutting boards and/or knife handles would try to enhance the finishing technic.  Both time with oxygen and heating in the sun would be appropriate as suggested by one of the folk on the woodworking thread.  
I don't know about the toxicity aspect but one of the major domestic tung oil producing sources was a small town halfway between Tallahassee and Perry FL.  The trees were beside Hwy 27 and tourists would occasionally ignore the signs and try to eat the nut/fruit with uncomfortable consequences.  
The thread above emphasizes that you should read the label to ensure the oil does not have any "dryers" (chemical additives that may include heavy metals) for impatient painters.  
I watched a video for treating knife handles that compared mineral oil, tung oil, and a couple of "wood treatment" products.  The tung oil was a clear winner.  Have not seen any videos comparing cutting board treatments yet.  
Might try "curing" a tung oil treated knives and a cutting board in a solar oven.  I never get around to using it for anything else.  

I'm friend is the owner of a high-end sushi restaurant in NY. In the past year or so, they've had to transition away from those beautifully made hangiri or sushi oke bowls (see images here: https://www.google.com/search?q=wooden+sushi+making+bowls&rlz=

Why? you ask.

Because the NY Dept of Health thinks that after the restaurant has been in business for at least 30 years, that wooden bowl presents a hazard and could potentially harbor ah, . . . well, I don't know what they think but they do have a RULE against it.

I think it's a crying shame and a horrific overreach in terms of what's real and what's unreal. The NY Health department is forcing them to buy plastic hangiri. The purpose of the pine or cedar bowl is to absorb the water from the rice. Cedar or pine is also used extensively in Japanese homes because of its insect repellant properties.

Yeah, I get that it's a soft wood, but it's also not a cutting surface. Short grain rice is cooked with kombu then transferred to the hangiri and seasoned in the bowl with rice vinegar, sugar (mirin most times) and salt.  https://www.justonecookbook.com/how-to-make-sushi-rice/#recipe  It's classically mixed with a wooden pallet made of  a similar soft wood. What is wrong with this process??? Cedar or pine is also used extensively in Japanese homes because of its insect repellant properties.

A plastic bowl doesn't do any of that.  And, a plastic bowl that sits around in a hot kitchen is more likely to house bacteria than a clean, dry, pine or cedar bowl. Worse, the plastic bowl goes through the dishwasher that uses at least 210F water and a 10 minute hot air dry. Just imagine the amount of microplastics that are released during that process.  

Worse, these health departments are working on state edicts, not national guidelines or (as far as I can see) even state edicts -- some of these "requirements" are local.  This is something new they've come up with that was not an issue 10 years ago, when I worked there. And, let's not even talk about the 147 billion sushi restaurants in Japan that STILL use classic or traditional hangiri without poisoning a soul to date.

I am incensed, but I'm off the soapbox now.  Thanks for letting me rant.

I think U.S. society has gone overboard re. cleanliness in certain ways, I think wooden kitchen items are just fine thank you, I think we're a bit too paranoid about bacteria anymore.  I mean yeah things shouldn't be filthy, but I just don't worry that much about it when it comes to the kitchen, a bit of exposure to dirt is probably healthy.

Hi Riona,

Many years ago I read an article by an MD speculating that our society’s interest in cleanliness was endangering our bodies’ ability to develop a resistance to diseases.  As you indicated, this wasn’t about a clean house vs a filthy house, but rather it was about a clean house vs a sterile house.

(https://en.wikipedia.org/wiki/Hygiene_hypothesis)

I use olive oil on my cutting board.  It seems to me any oil that is safe to eat is good for cutting boards.

For knife handles I don't car because knife handles don't usually touch food.  Though I usually use bacon grease as it is handy.  Apply a small about the dry with a paper towel.

My logic is that dried food is a good thing.  So if the cutting board gets rinsed with hot water and put away to dry it is safe to use.