Any finish is safe to use on a butcher-block table or countertop that will not be used as a cutting surface. If the surface won't be cut on, the answer is simple: Any film-forming finish you would normally choose for durability and appearance will be just fine (Photo 1).
Answer compiled from multiple comments to the question: Wood is dried just before being shrink-wrapped. The second the wood is unsealed, dust and moisture can start to absorb into the wood. Both cause issues with a clean finish and water can cause damage in some situations.
To seal butcher block with mineral oil, you simply apply the mineral oil generously, let it soak in, and wipe off the excess. You need to do it fairly regularly at first but then only about once a month after you've gotten through several applications.
Cutting against the grain causes fibers to raise up, giving your countertop a fuzzy feeling. Woodworkers discourage cutting on a butcher block countertop for this reason. But, if you believe you may use the countertop as a cutting surface for food, you'll need to use a food-grade sealant.
There are a variety of options for permanently sealing and waterproofing butcher block wood countertops, commonly used in kitchens. When considering sealers, there are two types available: penetrating and topical.
Follow these steps to easily waterproof your butcher block countertops with Polyurethane: Sand the counters until they're completely clean. Vacuum any dirt off the surface and apply a natural stain. Apply a thick coat of Polyurethane, a liquid coating that dries into a plastic.
While butcher block countertops do require routine maintenance, resealing the surface is only required after every 6-12 months depending on the level of use. The same goes for natural stone countertops, which must be resealed over time to maintain the original quality and look.
Apply two coats of mineral oil: When your countertops are dry, apply one coat of oil. You can pour a little bit at a time directly onto your counter and use the cloth to spread the oil around every inch of the counter. Let the oil soak in for half an hour or so before second application.
Olive oil, corn oil, and sunflower oil, should never be used to maintain a cutting board or butcher block. As touched on above, these oils experience rancidification – a process that yields a rank smell and unpleasant taste. As a cutting board touches your food, substances that can turn rancid should be avoided.
Food Grade Mineral Oil: This is the top choice for butcher blocks, and it's the primary ingredient in commercial sealing products. Look for food grade mineral oil in your local pharmacy – it's also sold as a laxative – and it'll be much cheaper in the pharmacy than in the hardware store.
In hardworking kitchens, food-safe oils and waxes are ideal finishes for butcher block because they're easy to wipe on, and, for the most part, there's no wait for them to cure.
Functional ones, like a butcher block, are ideal for food preparation. Decorative countertops are often installed to provide a more luxurious finish. Once sealed, wood countertops are sanitary for chopping meat, and hot pots and pans can easily be placed on the surface because wood countertops are heat-resistant.
Con: Butcher-block is susceptible to scratches, dings, and stains. If you plan on chopping directly on your countertops, you're going to end up marking things up a little (or a lot). That glass you dropped might just leave a dent, and the wine inside could settle into a stain. Pro: But they're easily restored.
Use three or more coats of Polyurethane on a butcher block, especially if you're applying an oil-based finish.
Periodically (once every several weeks, depending upon the use and household conditions), apply an even coat of mineral oil or Boos Mystery Oil to the work surface of your butcher block.
The formula has an acrylic base; polyurethane is added for better adhesion and durability. Polycrylic is not as durable as polyurethane and is meant to be used only on interior surfaces such as cabinets, furniture, and trim.
To answer the question in short, yes polyurethane is food safe for wood countertops. Per the FDA to become food safe it must be fully cured and dried to the touch which ranges in times.
The warmth of a wood countertop adds tremendous character to a kitchen. And the kitchen will be quieter because dishes don't clatter on wood the way they do on most other surfaces. Another plus: You can cut directly on a butcher block countertop, as long as the wood hasn't been varnished (think wood cutting boards).
Maple is one of the best and most popular for butcher block counters because it's hard and has a clear grain. Cherry and red oak offer rich color. Butcher block can also be crafted from bamboo (it works best with end-grain construction) and sustainably farmed exotics such as wenge, zebrawood, and iroko.
Butcher block has long been a favorite material of DIYers like ourselves! They are easy to work with - you can cut, drill, sand and shape them yourself - and require minimal tools. And from a design perspective, wood countertops lend a natural warmth to a space and with proper care, can last a lifetime.
Conditioners for Butcher Blocks
The beeswax will help in further prevention of drying and cracking of your butcher block. Note: Make sure to gently sand the countertops before applying the wax for the first time.
How To Condition. Over time, butcher-block countertops can lose their luster and look dull and dry. Give them a refresh with food-safe mineral oil or butcher-block conditioner (available at home improvement stores). Don't use a food oil, like olive or vegetable oil, which will oxidize on the surface and start to smell.
Bees Wax is safe and NON-TOXIC. ✔ ALL-IN-ONE WAX: BeesWax Conditioner for Woods, Butchers Block Surfaces, Bamboo And Leather. Works Great As A Natural Wood Cleaner, Furniture Polish, Wood Conditioner, Leather Seat Polisher And Protector. Great To Weather Proof Any Surface And As A Cleaning, Protector Wax.
Varnished butcher block countertops can be cleaned with Murphy's Oil Soap or with white vinegar and water (1 cup of vinegar to 1 gallon of water). White vinegar is a good antibacterial cleaning agent.