Wood or bamboo cutting boards are the best. They look nice and they keep knives sharp.
Unfortunately there are downsides too: They stain, warp, and crack. They can even grow mold!
There is one little known treatment that will make your wood cutting board or butcher block countertop impervious to water and resistant to stains: tung oil.
Tung oil is the oil extracted from the tung nut of the Aleurites fordii, a tree native to China. In woodworking, tung oil is called a “drying oil” because it naturally dries and hardens when exposed to air.
Tung oil is 100 percent natural and food safe. It’s better than both linseed oil and mineral oil for treating wood kitchen items like cutting boards and spoons.
Linseed oil was actually developed as a cheaper alternative to tung oil. It’s not naturally a drying oil but contains additives that turn it into one. The additives are not food safe, so linseed oil should not be used on wood that will come into contact with food.
Mineral oil is food safe but does not harden so it needs to be constantly reapplied. Not so with Tung oil.
How It Works:
Tung oil is rubbed into the surface of the wood. It soaks into the pores and gradually hardens there.
Once it hardens completely the pores of the wood are sealed and water cannot get in. That means that berry juices won’t stain, and meat juices won’t soak in.
It also means you can leave the cutting board wet and it won’t warp or crack.
How To Apply:
Rub 100 percent pure tung oil into the surface of the wood with a cotton rag or your hand. Massage the oil in for two to three minutes, and then wipe off the extra with a cotton rag. Wait about 10 minutes and you will see that some spots are still shiny while others are not.
Then apply a second coat. You will notice that you don’t need as much this time. Wipe and repeat for a total of three coats.
It will take 24 hours for the tung oil to dry completely. While it is drying set your cutting board out of the way and propped it up so it is not touching anything that would absorb the oil.
Depending on use, you will need to reapply a single coat one to three times a year. As the years go by the cutting board will become more durable and more beautiful, much like a well-seasoned cast iron pan.
Only untreated wood can be treated with tung oil, woods with paint or clear polyurethane finishes will not absorb the oil.
Woods previously treated with other oils should be washed with soap and water and allowed to dry before being treated with tung oil.
It never hurts to give your piece a quick sand with 320 grit sandpaper before oiling.
What to Buy
It’s not always easy to figure out what the right product for the job is. To treat wood or bamboo cutting boards, wooden bowls, spoons or knife handles, go with 100 percent pure tung oil.
Pure tung oil dries with a low luster. It darkens the wood and brings out the grain. The finished product will look much the way the wood does when wet.
Pure tung oil is completely food safe and can be used on anything that will come into direct contact with food. Most commercially available tung oil is “polymerized.” That means it was boiled in the production process. This creates a finish with a low sheen.
Unboiled, or raw tung oil is also available. It absorbs more easily and yields a lovely matte finish.
If treating a large butcher-block countertop, a tung oil finish will also work. Tung oil finish is not 100 percent tung oil. It has additives that make it absorb more quickly and dry with added shine.
Tung oil finish is less expensive and more widely available, however because of the additives it is not considered food safe. Depending on the product it is OK to use on a countertop or tabletop, because no one is going to eat directly off it.
Minwax makes a tung oil finish that is available at Home Depot and most hardware stores. Hope’s 100 percent tung oil is sold at my local hardware store. A good source for pure raw tung oil and great information on its many uses is Realmilkpaint.com.
Tung oil is the best way to make wood cutting boards, butcher-block countertops, wooden bowls, spoons, and knife handles look beautiful and last forever. Enjoy!