You'll find thousands and thousands of tutorials and products to help you finish, protect and maintain wood food surfaces on the web, be it cutting boards, butcher blocks or other surfaces where food is prepared and cut. The information and advice given varies so much from one site to another that it’s difficult to figure out which advice to follow! While some swear by mineral oil, specialty products or mixtures made from waxes and oils, Ardec would like to explore some specialized products as well as recommend a rather simple, yet environmentally friendly solution that offers an impressive protection and deserves to be better known: Tung Oil Finishing. Here’s why we prefer some of these specialty products and the Tung Oil Finishing to other existing, popular solutions.

The key for Durability: Avoiding Film-Forming Finishes

Wood Finishes can be divided into two broad categories:

Photo credit: Selkie Woodworks

• Film-forming or filmogen finishes, which form a thin film when the finish cures (i.e. lacquer, varnishes).
• Finishes which penetrate the wood and protect it from the inside rather than on the surface (penetrating oils, diluted varnish).

When a knife is going to be used to cut food on a wooden surface, film-forming finishes must be avoided since the knife will rapidly break down the film on the surface, which will let water, blood and juices seep into the wood. The finish will then become non-repairable and the finishing process must be repeated entirely, after sanding the surface completely.

Consequently, unless you have a decorative or service piece, you’d better opt for a penetrating finish, such as oil, oil/wax mixture or diluted varnish (which will not make a film): These solutions are easier to apply, maintain, and repair. Properly applied, penetrating finishes will protect the look of your wooden surface for many decades.

Drying and non-drying oils

The drying power of an oil is its ability to dry and cure when exposed to oxygen, thereby forming a polymer, a solid substance which is quite similar to plastic. If an oil dries and hardens within the wood fibers, it offers a stronger, more durable protection against knife marks and repetitive cleanings than a non-drying oil, which remains liquid and only saturates the wood fibers without hardening.

However, using a non-drying oil is not necessarily a bad choice, especially if it is used in combination with a wax, which will seal the wood, since the oil-saturated wood combined with the wax will prevent water, juice and blood to seep into the material. Nonetheless, protection will be less effective and less durable, since the wax will slowly wear off, and oil will slowly leak out of the wood with every wash. Consequently, using non-drying oil will require much more frequent applications than an oil that dries completely.

Does one absolutely need to Finish a wooden cutting board?

Photo credit: La huche à pin - Serge Caron

No, you don’t, especially if you own a board made from high density wood such as maple, cherry or birch, which are naturally highly resistant to marking. However, frequent cleaning with water, soap and sanitizing products will make the wood dry out very quickly and the color will eventually fade or tarnish. Wood cutting surfaces will wear faster and can potentially crack if exposed to too much moisture, or if they are too dry. Applying an initial protection and a regular maintenance will make the surface hydrated, easier to clean, while allowing the wood to retain its natural color. In the end, it’s a matter of personal preference, and mostly depends on how much you value the durability and the esthetics of your cutting board.

Traditional Options: Pros and Cons

Olive oil is recommended on multiple websites, but should be avoided at all costs! Olive Oil, like many cooking oils, is non-drying, but will eventually become rancid and sticky. This will give an unpleasant smell your food cutting surface while making it unpleasant to manipulate. It's a definite No-No!

Traditional (Raw) Linseed oil is a drying oil, and it is more fluid than tung oil. In its pure form, it dries in 5-7 days, so it is usually sold with added salt driers made from cobalt, manganese or zirconium. It has an orange color which will give a yellow tint to wood, which provides an antique look: some will appreciate this look, but others will want to avoid it. Overall, Linseed oil is an interesting alternative if the presence of drying agents do not bother you (they are deemed safe for food contact surfaces), but it offers a protection that will be a little less durable than Tung Oil.

Soy, Nut or Rice Bran Oils are non-drying but are unlikely to go rancid like olive oil. They are very easy to apply, but they do not harden in the wood fiber, making the protection much less resistant and durable than tung oil. However, as stated above, they can be a very interesting option when used in combination with waxes, being completely natural solutions and easy to apply without solvent, as it is the case with Tung Oil (see below).

Mineral oil is extremely popular with many professionals, particularly in English Canada and the United States. Although this is a byproduct of petroleum, mineral oil is odorless, colorless, tasteless, completely inert and approved as a food additive. Because it is inert, mineral oil is non-drying. If used, it should ideally be applied with a wax, and reapplied often, for a limited protection. It is nonetheless the most affordable solution and extremely easy to apply with a clean rag.

Oil and wax mixtures are extremely popular and are often preferred to non-drying oil on end-grain surfaces to keep the oil within the grain and prevent it to leak from the top to the bottom of the surface. It also provides a better overall protection and a nicer shine than non-drying oil used alone. Many professional woodworkers have their own oil/wax mixture recipe, which they sell to their customers. Beeswax, Paraffin or Carnauba wax will usually be melted and mixed with the oil in 1 part wax to 5 parts oil ratio. Should you opt for this mixture, keep in mind that Carnauba wax is the best option since it is the hardest wax and thus offers the best durability. Wax is not necessary when using drying oils, such as linseed or tung, but it will give a beautiful glossy finish to your board. Although oil/wax mixtures are much less resistant than drying oils, many will favor this alternative, even though it will have to be applied much more frequently. Application, however, is quite simple and easy. The choice is yours!

Specialized products for food surfaces abound and will simplify the task of those seeking a simple and easy to use product. Osmo, Rubio Monocoat, Odie's Oil and Prato-Verde products are mixtures of oils and waxes in different proportions that are very easy to apply and will provide very satisfying results as well. We'll get back to those shortly.

Tung Oil and its numerous benefits

Photo credit: KENPEI

Tung Oil is a vegetable oil usually sold in its pure form. It originates from the seeds of the Tung Tree's fruit, which is found in South-East Asia. The most interesting aspect of Tung Oil is that it has a very high drying power, meaning that it will penetrate the wood, dry and harden completely within the wood fibers. It is, however, a fairly viscous oil with a distinct smell (although it is not aggressive). For this reason, it is suggested to dilute Tung Oil with 50% Solvent to make its application much easier. A citrus solvent will have the benefit of giving a nice smell to the mix during the application, while eliminating any petroleum-based material to be used on your board and minimize environmental impacts.

Tutorial: Finishing a cutting board with Tung Oil

Our team at Ardec has a preference for Tung Oil finish because because it offers the most cost-effective, resistant and most durable solution when compared to other alternatives, while being easy to apply. It does not contain any additive or siccative (drying) agents. Does this finishing method sound like a good plan to you? See below how to proceed should you want to finish a new board or restore one damaged by wear and tear.

What you'll need:

• Pure Tung Oil and Solvent (Citrus Solvent is the best choice, see above)
• A pair of Nitrile gloves
• A clean plastic container with a capacity of 250 ml (8 fl. oz.) or more.
• Small, Clean Cotton Rags (at least 5 for the whole process)
• Small wood or plastic blocks or support for Finishing and Drying
• 800 grit sandpaper (optional)

Step by Step Instructions (see images below):

1. Make sure the board is clean and dirt free. Make sure that the board has been previously sanded.

2. For a total of 4 coats (recommended) on a medium sized cutting board, mix 30ml (1 fl oz. or 2 tbsp) of Tung Oil and the same quantity of solvent in a clean recipient. The mix can be kept for a long time if you prepared too much for your needs, and can be used to apply a maintenance coat every year.

3. Soak a cotton rag in the mixture of oil and solvent and apply the oil onto the surface in a circular motion, ensuring that the entire surface and the sides are covered. Do not leave any excess oil on the surface.

4. Turn the board upside down and lay the treated surface over wood or plastic supports on the 4 sides, and repeat the previous step for the back of the board.

5. Once the board is completely treated, wait for 15 minutes to allow the wood to absorb all the oil it can. Then, wipe off all the surfaces: There must not remain any oil on the surface. Depending on the drying environment, some oil might rise to the surface after a few hours. If this is the case, simply use a clean cloth and wipe again. Allow to dry 24 to 36 hours at room temperature in a dry place.

6. After having waited for the recommended drying period, touch the surface to make sure it’s dry before going forward. For an optimal finish with the smoothest surface, a light sanding with a 800 grit sandpaper is suggested before applying a new coat of oil. Then repeat steps 3-4-5 until you have applied 4 coats. Be aware that the wood will require (and absorb) less oil every coat as it becomes more and more saturated. Do not sand after the last coat.

7. Voilà! Your board is ready to use. See instructions below for washing and maintenance.

Tutorial: Restoring a cutting board finished with Tung oil

What you'll need:

• Pure Tung Oil and Solvent (Citrus Solvent is the best choice, see above)
• A pair of Nitrile gloves
• A clean plastic container with capacity of 250 ml (8 fl. oz.) or more.
• Small, Clean Cotton Rags (at least 5 for the whole process)
• Small wood or plastic blocks or support for Finishing and Drying
• 150-180 grit sandpaper for a board with average wear OR
• Sanding machine with 100-120 grit sandpaper for a board with heavy wear
• 800 grit sandpaper (optional)

Step by Step Instructions (see images below):

1. To restore a cutting board, a 150-180 grit sanding will be necessary to remove as much knife marks as possible. If the surface is too damaged or that the marks are too deep, you can use a more aggressive paper (100-120 grit) with a sanding machine.

2. Remove dust the surface and make sure the board is clean.

3. Depending on the wear of the board and the sanding that was done, you will have to apply one or two coats of oil/solvent mixture. Pour 15ml (1/2 fl. oz, or 1 Tbsp) of Tung oil, and the same quantity of solvent in a clean container, and mix thoroughly.

4. Soak a cotton rag in the mixture of oil and solvent and apply the oil onto the surface in a circular motion, ensuring that the entire surface and the sides are covered. Do not leave any excess oil on the surface.

5. Turn the board upside down and lay the treated surface over wood or plastic supports on the 4 sides, and repeat the previous step for the back of the board.

6. Once the board is completely treated, wait for 15 minutes to allow the wood to absorb all the oil it can. Then, wipe off all the surfaces: There must not remain any oil on the surface. Depending on the drying environment, some oil might rise to the surface after a few hours. If this is the case, simply use a clean cloth and wipe again. Allow to dry 24 to 36 hours at room temperature in a dry place.

7. After having waited for the recommended drying period, touch the surface to make sure it’s dry before going forward. For an optimal finish with the smoothest surface, a light sanding with a 800 grit sandpaper is suggested before applying a new coat of oil. Then repeat steps 3-4-5 until you have applied 4 coats. Be aware that the wood will require (and absorb) less oil every coat as it becomes more and more saturated. Do not sand after the last coat.

8. Voilà! Your board is ready to use. See instructions below for washing and maintenance.

Finish or restore your food contact surfaces with specialized products

As mentioned earlier, there is a range of specialized products for your food contact surfaces. They are usually more expensive than mineral oil finishes. However, thanks to their optimized formulation for food surfaces, these products save time while offering exceptional durability. Here are the ones that we recommend for an optimal finish and protection:

• Osmo's TopOil is an effective solution for protecting and maintaining food preparation surfaces, while enhancing the natural appearance of the wood. Made from a blend of oils and waxes, TopOil is a microporous coating that protects your food preparation surfaces from stains, dirt, and wear. Thanks to its exceptional resistance, this product is ideal for daily use. Moreover, it complies with European safety standards for food contact use once dry. TopOil is a ready-to-use product and requires 2 to 3 coats, and dries in 8 to 10 hours.

• Odie's finishing products, such as Universal Finishing Oil, Wood Butter, and Wood Wax, are all non-toxic and safe options for wooden food contact surfaces. They offer durable protection and extra shine, and can be used alone or in combination with each other. These products are ideal for all types of indoor and outdoor wood, including furniture, floors, doors, boats, bowls, kitchen utensils, and toys. Additionally, they contain natural UV inhibitors to protect the wood from sunlight, as well as a pleasant fresh citrus scent.

• Prato-Verde's Tavolo is an ideal solution for food contact surfaces. It is a water-based, non-toxic and food-safe finish that creates a durable and protective coating on wood surfaces. Tavolo is specifically formulated to resist water and food stains, making it perfect for use on kitchen countertops, cutting boards, and other food preparation surfaces. In addition, Tavolo is easy to apply and dries to a clear, matte finish that enhances the natural beauty of the wood. Its water-based formula also makes it environmentally friendly and easy to clean up. Overall, Tavolo is a reliable and safe option for those looking to finish or restore their food contact surfaces.

• Rubio Monocoat OilPlus 2C is a perfect finish for food contact surfaces for a variety of reasons. First and foremost, it is an incredibly durable and long-lasting finish that provides excellent protection against wear and tear. Additionally, it is non-toxic and contains no harmful chemicals or VOCs, making it safe for use on food contact surfaces. The oil is also very easy to apply, and dries quickly for faster project completion times. Additionally, Rubio Monocoat OilPlus 2C comes in a wide variety of colors, allowing you to customize the finish to your specific needs and preferences. Lastly, it is ideal for use on a wide range of surfaces, including wood, concrete, and even cork. Overall, Rubio Monocoat OilPlus 2C is a great choice for those looking for a safe, durable, and customizable finish for their food contact surfaces.

As you can see, you have plenty of choices! All of the products described above are excellent options for your food contact surfaces, so it's up to you to select the one you like the most depending on your tastes, the time you have to dedicate to this project, as well as your budget. These products apply similarly, but make sure to follow the manufacturer's instructions carefully to ensure optimal finish and protection!

Cleaning and maintaining your cutting board

Regardless of the finish on your board, cleaning it should only require hot soapy water and a small soft brush. Avoid putting the board completely in water, and never put a wood cutting board in a dishwasher. Significant temperature variations and plenty of water will damage the wood, and may break boards made from several parts glued together. After cleaning the surface, wipe it with a clean cloth and let the board dry standing on its long side.

An interesting alternative to regular soap is soap based on olive oil, recommended by Serge Caron of La Huche à Pin: That is an excellent degreaser 100% natural and biodegradable antiseptic properties that cleanses and nourishes surfaces wood without assaulting like vinegar or bleach that many use as a sanitizer .

To remove stains and odors on a surface, rub with salt and a clean rag after having rinsing it. For stubborn odors, you can also rub the board with a lemon or lime and let the acidic juice do its job. Let stand 2-3 minutes and wipe the board with a damp cloth, then let it dry standing on its long side.

An interesting alternative to regular soap, vinegar and bleach solutions is Olive Oil based Black Soap, recommended by Serge Caron, from La Huche à Pin: It is 100% natural and biodegradable solution which removes grease very efficiently. It has antibacterial properties, and will clean and nourish wood surfaces without being as aggressive on the wood as the aforementioned solutions (bleach and vinegar), which are very popular but can damage the wood over time.

Finally, it is safe practice to use different surfaces to cut vegetables and meat (especially chicken), to avoid cross contamination. A common practice is to use one side of your board for the vegetables and the other for the meat.

You are now an expert in wood surfaces finishing! What do you think of Tung Oil finishing, or any of the other recommended solutions above? Do you have a favorite finish, or tricks of the trade you'd like to share with us? We want to hear them!

Thanks

We extend our sincere thanks to Mr. Olivier Doray, owner of Atelier Toc Inc. which manufactures Le Temps des Cigales kitchen accessories * Le Temps des Cigales * as well as to Mr. Serge Caron, owner of La Huche à Pin. They are two passionate people who were kind enough to share their knowledge and experience with us. Sincere thanks as well to Mr. Jean-Pierre Coulombe, a hobbyist woodworker with a lot of talent, who lent us the cutting boards used for the tutorials in this article.