Mineral oil
The inert oil used to condition wooden boards and worktops. It is aftercare rather than cleaning, and it is not the same as a drying oil.
In detail
Mineral oil is a refined petroleum fraction, described by the regulator as a colourless, odourless, oily liquid used in medications, cosmetics, soaps, pesticides and as a lubricant. In cleaning it appears at the end of the job rather than during it: a wooden board or worktop that has been washed and dried is left dry and open-grained, and an oil finish fills that grain so water penetrates less readily on the next wash. The property that makes mineral oil the usual choice is that it does not dry. Unlike linseed or tung oil it does not polymerise into a film, so it does not go sticky, does not yellow and does not turn rancid the way a food oil will. It also has to be reapplied, because nothing holds it in place but the wood. Two boundaries are worth stating. Oiling is aftercare and not a substitute for cleaning — oil over a dirty board seals in what is there. And the regulator's sheet identifies the substance without addressing food contact at all, so the practice of oiling a board rests on woodworking and manufacturer guidance rather than on that sheet.
Properties
- Chemical name
- Mineral oil
- pH
- Not applicable
Why
- Mineral oil is explained by Porous and non-porous surfaces
Sources for this page
Sources
Right to Know Hazardous Substance Fact Sheet: Mineral Oil (RTK 1437)
New Jersey Department of Health · Government or regulator
Relied on for: That mineral oil is a colourless, odourless, oily liquid used in medications, cosmetics, soaps and as a lubricant. (background and mechanism only)