Food Oils

• The most effective and safe oils to use on wood bowls are oils that come from food themselves. Food oils, such as olive oil, vegetable oil, walnut oil, sunflower seed oil and safflower oil, can be used. It takes several application of the oil before the oil seeps into the wood enough to create a water-safe finish, but the finish will eventually build up enough to protect the bowl from water and other contaminants. This kind of finish must continually be reapplied to the wood for best results.
  
  

Natural Oils

• Natural oils can be used on wood bowls for protection as well. If the bowl is used for food substances, then the oils used to finish and protect the wood should be food safe and FDA-approved for use with food products. Some grades of mineral oil, food-grade linseed oil, tung oil and mixed finishing oils are approved for use on wood bowls used for food consumption. These oils take several applications before they fully seal the wood, but after the initial applications, there is little need to reapply the oil.
  
  

Hard Finish

• Some wood finishes produce a hard, impenetrable finish that prevents water and anything else from getting into the wood. Some hard finishes are safe to use with food consumption, but others are not. Check the finish container before applying to ensure the finish is safe for food. Finishes such as urethane, Nordic oil and butcher block oil create a hard finish on the surface of the wood. Only one application of the finish is necessary to completely seal and protect the wood.
  
  

Finishes Over Time

• Another way to finish a wood bowl is to allow the wood to seal itself naturally, over time, with the oils used in food production. This kind of finishing can take a long time, but the finish is effective. It is important to simply wipe the bowl clean with a damp cloth after each use to prevent the bowl from cracking or warping before the oils penetrate into the bowl. Don't use soap; it will strip the oily finish, and you will have to start over to keep the wood protected.