How to Oil a Wood Cutting Board

The oil that does not go rancid

Mineral oil (USP / food-grade) is a non-drying oil that sits in the fibre and does not polymerize into food-rancid film. Board creams add beeswax for a slightly more water-resistant face. Tung and polymerizing “board finishes” are a different, longer job. Olive, sunflower, and butter are pantry oils that smell like old nuts in month two.

15–20 ml is a tablespoon-ish for a 40 × 30 cm face. A 60 × 40 cm butcher block may want 40 ml. Underside too, or the board cups.

When, and what the board is telling you

Ashy colour, raised grain, water soaking in within a few seconds: oil tonight. A well-kept board needs it every 4–6 weeks of real use, less in a humid kitchen, more in heating season. After a hard scrub or a lemon-and-salt deodorise, oil the same day because you just opened the grain.

• Dry completely before oil — oil on a wet board traps moisture
• Face, edges, underside
• Overnight, then wipe; leftover puddles stay tacky
• Stand on edge to dry, same as after washing — see wood vs plastic

Oil will not fill a trench

If the chef’s knife has cut 3 mm valleys, sand to 120 then 180, wipe dust, then oil heavily for two nights. Deep cracks that catch a fingernail can harbour what you hoped wood would not. Retire or have it planed. Store away from the damp of the sink and the knives’ drip — store knives on a strip, not on the board.