Selecting a cooking oil used to be a case of "vegetable oil, olive oil or
butter?". No longer. These days it is easy to find all kinds of fancy oils.
This is a mixed blessing — it allows far more flexibility, but makes
selecting the best oil for the task a lot harder.
Ultimately, the original three are enough to provide an adequate solution for
any kind of cooking. But then, jeans, a t-shirt and a suit provide an adequate solution to clothing. Having access to a few
extra oils is a great way of adding a little more variety to food. On the other
hand, it's not worth going out and buying a bottle of every kind of oil for home
use — there's considerable overlap in styles, and oil doesn't keep
A note on terminology: strictly speaking, an oil is liquid at room temperature whereas a fat is solid. The distinction is often ignored when cooking — butter in particular will melt with very little heat, so is often used as a cooking 'oil'.
Oils can be classified by two characteristics: flavour and smoke point.
For a few oils, stickiness and reactivity can also be relevant issues.
Finally, some oils are sold with added flavourings.
Oils with a strong flavour can significantly alter the taste of the food.
Sometimes this is desirable — the distinctive taste of sesame oil is an
important part of many oriental recipes. Sometimes, though, strong oils can
ruin a meal. When working with delicate fish in particular, the wrong oil can
kill the meal's flavour.
Although not strictly speaking a cooking issue, flavour makes even more of a
difference when mixing a salad dressing. Here the oil usually forms a
significant part of the end flavour, so selecting the correct oil is
When an oil is heated above a certain temperature, it will start to
decompose. The temperature at which this happens is called the smoke point,
because most cooking oils will give off nasty smoke when they break up. The
smoke point is lower than the flash point, which is where the oil catches
fire. None the less, it is extremely important never to exceed the smoke point
of an oil. As well as a nasty taste and smell, the smoke from some oils contains
various carcinogenic compounds.
For low temperature cooking, the smoke point is largely irrelevant. When
frying or oven cooking at higher temperatures it is sometimes a significant
issue, and when making a sauté or stir fry it should be a primary
A few oils are not particularly good at preventing food from sticking to the
pan. This can be a problem if food is being fried for more than a few
Most oils are fairly inert and will not react with food or pans. A few
obscure oils have been known to go badly with certain foods and pan surfaces,
however — when selecting an uncommon oil, it may be wise to check whether
it reacts with anything.
Some oils claim to have various health benefits. Separating the genuine
differences from the kooky pseudo-science is rather tricky — chances
are, the only way that this is at all relevant is that certain otherwise obscure
oils can easily be found in health food stores.
Recently, certain producers have started making oils which come pre-flavoured
— popular choices are garlic, lemon, chilli, ginger, basil and
rosemary. This is a slightly controversial topic. Personally, I prefer to add
flavourings when cooking; others find pre-flavoured oil more convenient. Some
things to bear in mind:
- The smoke point of pre-flavoured oils will be lower than that of the
- Pre-flavoured oils will not last as long before they start to go
- Some people are concerned about botulism
when using flavoured oils. This may be an issue for home made oils, although its
significance is debatable, but pre-made oils should contain lots of nasty additives to eliminate any risk. There are plenty of
ways of making yourself ill when
cooking, most of them far more common than botulism.
Popular Cooking Oils
Now for some of the more popular cooking oils. Note that the smoke points
will vary considerably depending upon whether the oil has been refined. There
are various tables of smoke points around, all of which are only very rough
approximations and many of which are misleading on the issue of refined
- Sunflower oil, Vegetable oil, Rapeseed oil, Canola oil
- Fairly little taste. Fairly low smoke point.
- Slight taste, usually not noticeable in the end product. Very low smoke point.
- Olive oil
- Moderate to strong flavour depending upon the style. Medium smoke
- Sesame oil
- Very strong flavour, plays an important part in certain Japanese and
Chinese recipes. Medium smoke point. Do not use this oil in salad dressings
— it will drown out the flavour of the other ingredients.
- Grapeseed oil
- Very mild flavour, very high smoke point. It remains slippery for longer
than most other oils. Ideal for sautés, making crunchy jacket
potatoes and high temperature oven cooking.
- Peanut oil
- Noticeable flavour, high smoke point. Often used in salad dressings.
- Walnut oil
- Noticeable flavour, fairly low smoke point. Better for salad dressings
than for cooking.
- Avocado oil
- Noticeable flavour, but not overpowering. Extremely high smoke point.
Very viscous — less of this oil is needed when cooking.
- Bacon grease
- It is rumoured that some people actually use this stuff for
cooking. It has a baconish flavour, a very low smoke point and is prone to
catching fire. Other variations on this theme include lard, dripping and ghee — these are all fats and aren't particularly good for frying.
If I could only have a single oil, I would go with grapeseed.
It's not a conventional choice, but it's not very expensive and the high smoke
point and low flavour make it fairly versatile. Others have different opinions
— different oils suit different cooking styles. Experimentation is encouraged.