Peanut Oil

Why peanut oil is rated low

Peanut oil is low FODMAP, because of what the oil is. It is a pure fat, and FODMAPs are water soluble, so they stay behind with the solids when the nuts are pressed rather than following the oil into the bottle. No FODMAP subgroup is recorded for peanut oil, and the qualitative ladder reads LOW at Any typical portion, which covers the amount you would fry, roast or dress food with. This is the same principle that makes garlic infused oil work, and it means the oil is judged on its own terms rather than inheriting anything from the nut it came from. Low does not mean invisible, though: the oil is nearly always carrying something else into the pan, and a satay or chilli sauce built on it is a different question entirely.

What changes your risk

• Serving size Any typical portion covers cooking and dressing amounts, from a slick in a wok to a pan of oil for frying. Oil is not something people eat by the cupful, so Any typical portion is the reference point.
• Solid pieces left in the oil An oil only stays clear of FODMAPs while it stays oil. Garlic cloves, onion, shallot or spring onion bulb left sitting in a bottle or a hot pan put their water soluble FODMAPs within reach again, so infuse with the solids in, then strain them out and discard them rather than leaving them floating.
• What the oil carries Peanut oil rarely goes into a dish alone. Frying onion and garlic in it, or using it as the base for a satay, laksa or chilli crisp, means the finished oil carries whatever it was cooked with. The bottle is low, the sauce is a separate judgement.
• Peanut oil is not peanut butter Pressing separates the fat from the solids, so the oil and the whole nut behave differently, and a spoon of peanut butter or a bowl of peanuts is its own entry with its own serving. Do not read the oil's rating across onto the nut products in the same cupboard.
• Blends and flavoured bottles Bottles sold as groundnut or peanut oil are sometimes blends, and flavoured or aromatic versions can carry garlic, onion or spice pastes. Plain, single ingredient oil is the straightforward one, so the ingredients list settles it.

What else works

Peanut oil is already low, so the honest answer is that most plain oils sit the same way: olive oil, rapeseed or canola, sunflower, rice bran, sesame and plain coconut oil all work in the same roles, and garlic infused oil is the one to reach for when a recipe wants a garlic backbone. Plain butter fills the job in baking and pan cooking. The things that do not carry across are the peanut foods that are not oil, and the sauces built on the oil: satay sauce, peanut dressings and chilli oils with fried garlic and shallot solids in the jar all bring more than fat with them. For a nut hit alongside it, peanuts, walnuts, macadamias, pecans and pumpkin seeds are the reliable ones, while cashews and pistachios are not.

How to keep it low

Buy a bottle whose ingredients read as one oil, since groundnut branded bottles are sometimes blended and flavoured versions can hide aromatics. Store it capped in a cool dark cupboard rather than beside the hob, because light and heat turn it stale, and use refined peanut oil for high heat frying and a cold pressed one where you actually want the nutty flavour. To make your own garlic infused version, warm whole cloves gently in the oil to draw out the flavour, then lift every piece out and strain before bottling, since it is the solids rather than the oil that carry the FODMAPs. When ordering out, a stir fry cooked in peanut oil is fine in principle, but the same wok almost always starts with garlic and onion, so ask about the aromatics rather than the oil.

Common questions

is peanut oil low fodmap

Yes. Peanut oil is rated LOW at Any typical portion, because it is pure fat, and no FODMAP subgroup is recorded for it.

does peanut oil have the same fodmaps as peanuts

No, the oil is judged separately. FODMAPs are water soluble and stay with the solids during pressing rather than carrying into the fat, so the oil has its own rating and peanut butter and whole peanuts have theirs.

how much peanut oil can i cook with

The rating covers Any typical portion, which is the amount you would use to fry, roast or dress food. Any typical portion is the serving to work from.

is garlic infused peanut oil low fodmap

Yes, as long as no solid pieces are left in it, because garlic's FODMAPs are water soluble and do not dissolve into oil. Warm the cloves in the oil for flavour, then strain them out and discard them before storing.