Once fully cured, polyurethane is food safe and meets FDA requirements for food processing applications. It offers exceptional mechanical strength and resistance to harsh environments. Also, polyurethane does not aid fungal, mold, or mildew growth, making it a perfect choice for food-related wood projects.
Polyurethane is used in many different woodworking projects, from wooden spoons to cutting boards where it comes in contact with food.
However, the term “food safe” can be misleading, and many people are unsure if polyurethane is safe for use with food.
This article clarifies the topic of food-safe wood finishes and specifically addresses the safety of using polyurethane in food-related woodworking projects.
Polyurethane is an artificial material used to protect wooden surfaces from damage. It is created by combining polyol and isocyanate to form a hard coating.
There are two types of polyurethane: oil-based and water-based.
Oil-based polyurethane is tougher and more resilient than water-based polyurethane, while water-based polyurethane is more environmentally friendly and easier to clean.
Polyurethane is safe for use with food once it has fully cured. When cured, the finish creates a hard surface that is safe to use with food.
It usually takes about 30 days for polyurethane to cure fully, depending on the product and environmental factors.
During the curing process, the solvents and bonding agents in the polyurethane evaporate or bond with oxygen molecules, creating a safe surface.
However, some polyurethane products may contain hazardous chemicals or additives that can seep into food.
When selecting a polyurethane product for a food-related wood project, choose one that is food-safe and meets FDA requirements for food processing.
To ensure that your polyurethane finish is safe for use with food, it’s essential to apply and cure it correctly.
Before applying the finish, ensure the wooden surface is clean and dry.
Apply the finish in thin, even layers, allowing each polyurethane coat to dry thoroughly before adding the next.
Finally, after applying the last coat, let the finish cure for at least 30 days before using the wooden surface for food-related purposes.
If you can smell the finish, it has not yet fully cured.
Although you can use different techniques to get rid of the polyurethane smell, it is best to allow the workpiece to naturally cure to ensure that it is food safe.
Follow these recommendations to ensure your polyurethane finish is long-lasting and safe for food contact.
Although polyurethane is commonly used to preserve and improve the appearance of wooden surfaces, there are also other food-safe finishes that can be utilized for food-related wood projects.
For instance, natural oils like mineral, walnut, or linseed oil are preferred for wooden utensils and cutting boards.
Shellac, a food-safe finish that has been in use for many years, is also a viable option.
Besides, beeswax and carnauba wax are safe for use in food-related wood projects.
When working on food-related wood projects, choose a wood finish that is safe for food contact.
There is a lot of ambiguity and misleading information about which finishes are safe for food and which are not.
Nonetheless, the reality is that all wood finishes that harden into a film are safe for food use, such as natural oils, shellac, and polyurethane.
This is because, as the wood finish cures, the solvents and bonding agents in it either evaporate or bond with oxygen molecules, creating a durable, inert film similar to plastic that is safe for use with food.
Historically, lead was present in many wood finishes as a metallic dryer, which was deemed hazardous.
Nonetheless, lead has been prohibited from wood finishes for almost 50 years, and other metallic dryers are currently used in small quantities that pose no harm.
Consequently, contemporary wood finishes are safe for food contact as long as they are thoroughly cured.
When selecting a wood finish for food-related projects, one of the critical aspects to keep in mind is the curing period of the finish.
Polyurethane, for instance, requires roughly a month to cure completely. Typically, if you can still smell the finish, it has not finished curing.
Allow the finish to cure and harden fully so that any harmful solvents evaporate away.
After the finish has entirely cured, it becomes safe for use with food.
All wood finishes that create a hard film after drying is safe for use with food, including polyurethane.
The harmful metals found in wood finishes have been outlawed. As modern wood finishes cure, the solvents and bonding agents evaporate away or bond with oxygen molecules, creating a hard, inert film that is safe to use with food.
The critical aspect is to allow the finish to cure entirely, ensuring that all hazardous solvents have dissipated and the finish has completely hardened.
Yes, polyurethane is a suitable option to finish a cutting board, as it creates a sturdy and water-resistant surface. Nonetheless, following the appropriate application and curing instructions is crucial to ensure the finish is completely cured and safe for food contact.
Glass, marble, granite, and other hard materials are not recommended for cutting boards as they can blunt knives rapidly. Moreover, porous materials like bamboo or wood that are not maintained properly can foster bacteria and pose food safety risks. It is vital to choose materials that are food-safe, effortless to clean, and do not damage knives.
Yes, there are food-safe clear coat products that do not contain harmful substances or additives, such as natural oils, shellac, and polyurethane.