None of which is especially appetising, but it is expedient for the manufacturer. The process makes the oils bland (appealing to customers) and gives them a long shelf life, which suits retailers. It also gives them a high ‘smoke point’ (see previous page).
A final note: the way you store oil is important. Taking a sniff from that expensive bottle of nut oil to find it has gone rancid already is infuriating – but most of us just don’t use them up fast enough, and nut and seed oils (except sunflower oil) can ‘turn’ in a couple of weeks, especially if you keep them in a warm spot by the cooker. Keep them chilled and they’ll last years – I’ve got a shelf in the fridge door reserved for posh nut oils.
A good compromise: keep a small bottle (ideally pottery not glass or metal) within arm’s reach, and refill it as necessary from a bottle kept in a cool cupboard.
What cooking oil to use for what meal
Coconut oil
Good for vegan baking as it is solid, like butter, at room temperature. But it’s nearly all saturated fat, and has no omega-3.
- Monounsaturated: 6%
- Polyunsaturated: 2%
- Saturated: 92%
- Omega-3: negligible
Extra-virgin olive oil
Use for salad dressings and drizzling over finished dishes. The fairly low smoke point means it’s not great for searing meat and vegetables or roasting meat.
- Monounsaturated: 78%
- Polyunsaturated: 8%
- Saturated: 14%
- Omega-6/3 ratio: 13:1
Sunflower oil
Works for general frying and as a base for dressings and mayonnaise. Look out for high-oleic sunflower oil (made from particular varieties) with more omega-3.
- Monounsaturated: 20%
- Polyunsaturated: 69%
- Saturated: 11%
- Omega-6/3: ratio 40:1
Rapeseed oil (aka canola oil, in the US)
Good unrefined, cold-extracted oil is nice for salad dressings and gentle braising, such as courgettes. Refined rapeseed oil has lower micronutrient content.
- Monounsaturated: 62%
- Polyunsaturated: 31%
- Saturated: 7%
- Omega-6/3: ratio 2:1
Groundnut oil (aka peanut oil)
High in vitamin E and good for frying – fish, for example. Generally highly refined but the unrefined oil has a pronounced nutty flavour.
- Monounsaturated: 48%
- Polyunsaturated: 34%
- Saturated: 18%
- Omega-6/3: ratio 32:1
Avocado oil
Use for salad dressings and stir-fries. It’s very bland so won’t overpower delicate flavours, and contains vitamin E.
- Monounsaturated: 70%
- Polyunsaturated: 14%
- Saturated: 16%
- Omega-6/3: ratio 13:1
Flaxseed oil
Good for adding to cereal and smoothies to boost omega-3 levels for non-fish-eaters, but it has a fishy smell. Not for cooking as it has a very low smoke point.
- Monounsaturated: 62%
- Polyunsaturated: 31%
- Saturated: 7%
- Omega-6/3: ratio 2:1
Walnut oil
Add to salad dressings and coffee and walnut cake (keep the oven temperature below 160C), but it goes rancid quickly at room temperature.
- Monounsaturated: 24%
- Polyunsaturated: 67%
- Saturated: 9%
- Omega-6/3: ratio 5:1
Lemon oil
In its pure form, lemon oil can be used for flavouring icing, chocolates, frosting, cakes and other confectionery. Being made from pressed fresh lemons, it is suitable for vegetarians and vegans. It’s not suitable for cooking, however, so if you’re looking for a bit more flavour to your regular cooking oil, some brands and supermarkets sell lemon-infused olive or rapeseed oils.
This article has been updated with the latest information.
