Cooking oils and fats
The ideal cooking is that which is as gentle as possible. Some purists even go so far as to eat only raw food, or food that is cooked to the limit with steam, in order to keep the nutritional properties of the food as much as possible.
Therefore, if one decides to cook one's food, the question that arises is: what are the optimal fats for cooking, and up to what temperatures can one go without degrading the nutritional properties or, worse, causing compounds that are harmful to one's health?
Can we cook the fat?
The answer to this question is: yes, but as little as possible, and at the lowest possible temperature.
Cet article fait partie du guide Blooness, le guide de l’alimentation humaine idéale, dont vous retrouverez le sommaire ici 🌱🥑
Indeed, cooking fat, and especially overcooking oils, can lead to many changes in their nutritional properties, including :
- The destruction of antioxidants. As a reminder, antioxidants are molecules that slow down or prevent the oxidation of other chemical substances in contact with them. They fight against oxidative stress, which is precisely responsible for cellular ageing.
- Overcooking fat can also lead to oxidation of fatty acids (lipoperoxidation).
- Cholesterol oxidation (formation of oxysterol).
- Hydrolysis of fatty acids, i.e. the chemical decomposition of fatty acids
- Polymerization of fatty acids (anarchic molecules).
- Formation of TRANS fatty acids (fatty acids with poor conformation; they are particularly harmful).
- The formation of toxic (for some potentially carcinogenic) neoformed products.
The aim is to minimise the negative effects of fat cooking. And to achieve our goal, we are going to favour certain oils that are more resistant to cooking than others. To do this, the indicator that will guide us is the famous "smoke point".
Smoke point, késako?
The smoke point is the critical temperature at which the oil produces toxic and potentially carcinogenic compounds, such as benzopyrene or acrolein. To put it very simply, this is the point at which smoke is detected, and it is at this point that cooking causes the negative points that we mentioned earlier.
This is why barbecues have a bad health reputation, since they produce a lot of black smoke, a signal about the composition of harmful elements.
However, pan-frying can be done at varying temperatures, ranging from around 50°C for the mildest cooking, up to 150°C and sometimes more. It goes without saying that the milder the cooking, the better it will be for our health, even if it must be acknowledged that certain "pleasure" recipes, which we will not abuse, require quick cooking.
In order to determine which fats are the least sensitive to cooking, it is therefore sufficient to list them by smoke point level. But before going any further, we must first distinguish between refined and unrefined oils.
Refined oils VS unrefined oils
Refining is an industrial process to modify certain characteristics of the oil, for example, to make it odourless or tasteless, or to make it more heat stable.
The advantage of refined oils is that they will be less sensitive to the heat of cooking or frying. However, this process has several disadvantages: it can use chemical compounds, and can alter some of the vitamins and antioxidants that make up the processed oils.
It is therefore preferable to opt for unrefined oils which, although their smoke point will be lower, will be more nutritious and less processed, provided you opt for gentle cooking!
The top unrefined oils and fats for cooking
Here is the list of unrefined oils, classified by smoke point. In other words, the oils that have the highest smoke point are those that will lose their nutritional properties the least during cooking and will be the most beneficial for the body.
The green fats that dominate the top of the classification are therefore to be preferred, while the red fats are not recommended for cooking, since their smoke point is low.
- Clarified butter (Ghee) - 252°C
- Virgin olive oil - 216°C
- Macadamia Oil - 200°C
- Goose/duck fat - 190°C
- Coconut oil - 177°C
- Oleic sunflower oil* (not to be confused with simple sunflower oil!) - 160°C
- Peanut oil - 160°C
- Extra virgin olive oil - 160°C
- Butter - 120 to 150°C
- Rapeseed oil - 107°C
- Linseed oil - 107°C
- Sunflower oil - 107°C
* Sunflower is said to be oleic when its content of monounsaturated fatty acid of the oleic type is higher than 75 %.
As can be seen in this classification, sunflower oil and butter are two types of fat that are not recommended for cooking. However, they are oils that are used extensively.
Rapeseed, walnut, hazelnut, linseed oils, etc. can be relatively healthy, but they should be limited or even banned for cooking, given their smoke point. They are therefore preferred for seasoning.
Peanut oil has an interesting smoke point, but is nevertheless rich in omega-6, which we are trying to reduce in favour of omega-3.
Conversely, olive oil, oleic sunflower oil, coconut oil, macadamia oil, and finally goose/duck fat and clarified butter have the highest smoke points and are therefore to be preferred for cooking.
Top refined cooking oils
While it is better to ban refined oils in favour of unrefined oils, refined oils can be useful in the case of high-temperature cooking, particularly for frying. It is therefore interesting to know which oils should be preferred in such cases, in order to mitigate the harmful effects of intense cooking.
- Refined olive oil - 242°C
- Sunflower oil oleic refined - 232°C
- Refined coconut oil - 232°C
- Refined peanut oil - 227°C
- Refined sunflower oil - 227°C
- Refined rapeseed oil - 204°C
Thus, in the event of having to choose between different refined oils, the classic nutritional advice all converges on olive oil. On the other hand, coconut oil can be a good alternative.
As you can see, fat should ideally be eaten undercooked, as a seasoning. Nevertheless, if certain recipes and certain contexts require cooking, then olive oil, macadamia oil, coconut oil, clarified butter, and goose or duck fat should be preferred.
In the near future, we will see what the best cooking methods are, and what equipment is recommended to mitigate the harmful effects of cooking, while maintaining its benefits.