Healthy Living

Can you use olive oil for both hot and cold preparations? Can you bake with rapeseed oil? And why is peanut oil ideal for frying? We open a booklet on the most common vegetable oils and reveal which ones are best suited for heating.

Each type of fat is a composition of both saturated and unsaturated fatty acids, but in very different percentages. If an oil or other type of fat contains mainly saturated fatty acids, it ends up in that category (saturated fats). If the unsaturated fatty acids play the main role, the oil or fat type is labelled 'unsaturated fat'. In the case of unsaturated, a distinction is made between single and multiple.

A touch of chemistry

Fatty acids are thus divided into three groups: saturated - monounsaturated - polysaturated. To understand how that works, we need to go back to chemistry. In chemical terms, saturated fatty acids have a saturated carbon chain (no double bonds). Monounsaturated fatty acids have only 1 double bond (oleic acid is the main), polyunsaturated fatty acids have several double bonds in the carbon chain and contain essential fatty acids.
Both the saturated and monounsaturated fatty acids can be produced by our body. Its intake is therefore not necessary. Polyunsaturated fatty acids, including linoleic acid and alfalinonic acid (ala or LNA) abbreviated cannot be produced by our body and must be supplied through the diet..
Polyunsaturated fatty acids are further divided into omega-3 (e.g. alfalinonic acid), omega-6 (e.g. linoleic acid) and even omega-9 fatty acids, which has to do with the positioning where these double bonds occur (at which atom).

What are the recommendations for daily intake?

1. Saturated fats The High Health Council (HGR) recommends in a 2016 report that the intake of saturated fats, such as those in coconut oil and palm oil, should be kept as low as possible with the upper limit of 8 to 10% (depending on the species) of total energy needs (2000 kcal per day for women, 2500 for men). The American Heart Association (AHA) and the American College of Cardiology (ACC) even recommend that adults who want to keep their bad cholesterol (LDL) within acceptable limits, even to not exceed 5 to 6%. Butter, cocoa butter and lard are also part of this fat family.
2. Monounsaturated fats Because monounsaturated fats do not play a role in the prevention of nutritional-related diseases, nor do they contain essential fatty acids (our body can make them own) the HGR does not formulate recommendations on this. On the other hand, there is evidence that a diet in which saturated fatty acids are replaced by unsaturated leads to a reduction in LDL concentrations. And that switchover not only has an effect on LDL (bad cholesterol), it also affects the plasma ratio of total cholesterol/HDL cholesterol.
   According to the Nordic Nutrition Recommendations (NNR), the ideal scenario is that 10-20% of the total energy requirement consists of monounsaturated fatty acids. Moreover, they argue that the intake of unsaturated fatty acids in general (both single and multiple) should be at least two thirds of total fat intake.
   The main monounsaturated oils are olive oil, rapeseed oil and peanut oil.
3. Polyunsaturated fats The polyunsaturated are important in any case to reduce the LDL fraction and the risk of coronary heart disease while at the same time helping to increase plasma-HDL cholesterol levels. Some also play an anti-inflammatory role. Therefore, an intake is recommended corresponding to at least 6% of the total energy requirement.
   The main polysaturated oils are sunflower, corn, soy, wheat germ, grapeseed, nut, flaxseed and safflower oil. Nuts are therefore also an important source.

Our diet is usually already well equipped with omega-6, but omega-3 fatty acids are often too low, which is why it is a good and healthy idea to eat a lot of oily fish and use more often oils that contain a lot of alfalinonic acid (omega-3 fatty acids) .

does that translate into the kitchen?

Unsaturated fats therefore help in fighting the bad cholesterol (LDL) they and contain a lot of omega-3, 6 or 9 fatty acids. If you don't put more than a knife point healthy fat dust* on your sandwich and use a maximum 2 tbsp fat (healthy vegetable oil suitable for heating) per person to prepare a meal, you're doing a good job of fat intake. But the choice is not at random, because not all vegetable oils lend themselves to hot preparations or heating. Especially oils containing a lot of omega-3 fatty acids, such as flaxseed and walnut oil, oxidize quickly and are therefore only suitable for cold applications. That has to do with the temperature at which those oils burn. That temperature, in which an oil dissolves and starts smoking, is called the smoking point. When oil is heated beyond its smoke point, it will oxidize and in doing so harmful or carcinogenic substances (polycyclic aromatic hydrocarbons or PAHs) can form. Only oil seals with a high smoke point (preferably above 220 °C) are therefore suitable for use when roasting or frying. Butter, for example, burns at 177 °C.

*Sporadically a lump of butter does not hurt because that is a supplier of fat-soluble vitamins A and D. Margarine adds those vitamins. see also article : So many types of cooking fat. What to choose?

Below, we review the appropriate applications for the most important and common oil varieties.

1. Corn oil Corn oil or corn seed oil - the name says it itself - is squeezed out of corn germ. It is an oil with a golden yellow color and a neutral taste that is widely used in our kitchen.
   • Suitable for cold and hot preparations. As far as the smoking point of refined maize oil is concerned, the information varies according to the various sources: it ranges from a limit of 210 °C to 246 °C. Most sources do not recommend heating polysaturated fats in general above 200 °C or even 180 °C.
   • Contains few omega-3 fatty acids but almost 56% linoleic acid (an omega-6 fatty acid)
   • Contains vitamin E, an important antioxidant that ensures healthy skin and hair.
2. Sunflower oil is squeezed from the seeds of the sunflower and is one of the most widely used oils worldwide. It has a soft taste and a pale yellow colour and is often part of mixed salad oil, cooking oil or margarine.
   • Suitable for both cold and warm preparations. Its smoking point is around 220 to 230 °C.
   • Almost 90% consists of unsaturated fatty acids, of which about 63% are linoleic acid (omega-6 fatty acid), but it contains few omega-3 fatty acids. Like corn oil, it's rich in vitamin E.
3. Soybean oil Also soy oil is used worldwide and is even the frontrunner. It has a mild taste and is often processed in salad oil, margarine and baking/roasting products. The real all-rounder and also the cheapest type of oil, but it is not sustainable for long. She is squeezed out of soybeans and then refined.
   • You can use them both cold and hot. Since her smoking point hovers around 230 °C, it is also suitable for baking and roasting.
   • Contains about 80% unsaturated fats, of which relatively much alfalinolic acid (omega-3) and just over 50% linoleic acid.
4. Flaxseed oil is squeezed, both hot and cold, from the seeds of the oil flax plant. She has a golden yellow color and an aromatic taste.
   • Only suitable for cold preparations (in a dressing or in a cold sauce). The smoke point is below 180 °C.
   • Contains about 87% unsaturated fatty acids and is mainly rich in omega-3 (about 54 g per 100 g of oil).
   • Flaxseed oil and broken line seeds have a beneficial effect on bowel transit and contribute to a good bowel movement.
5. Rapeseed oil Is pressed hot or cold from the seeds of the rapeseed plant, a beautiful plant with a weeë scent and cheerful yellow flowers. Rapeseed oil is made from the rapeseed plant, the wild variant of the rapeseed plant. The oil has a yellow color and a neutral taste. Cold pressed, she is intensely yellow and tastes a bit like nuts. Cabbage and rapeseed oil are often processed in margarine and biscuits.
   • Suitable for both cold and warm preparations, as the smoke point fluctuates around 240 °C.
   • Contains a lot of vitamin E and other oxidants.
   • A healthy oil consisting of 90% unsaturated fatty acids, of which about 10% essential omega-3 (alfalinonic acid). 60% of fats are monounsaturated, hence the high smoke point.
6. Nut oil: walnuts and hazelnuts Quickly becomes rancid and is only suitable for cold preparations such as dressings and vinaigrettes.
7. Olive oil A yellow to green oil that is pressed from the fruits (with their kernels). For olive oil there are large quality differences (and price differences) according to the olive variety, the terroir on which they grow and the moment when they are harvested. The scents and flavours also vary enormously and can range from fruity and subtle to strength and peppery.
   • Approximately 82% consists of unsaturated fats, mainly monomic, and is rich in antioxidants and oleic acid, an omega-9 fatty acid that is not essential and can be produced by the body from unsaturated fatty acids.
   • In olive oil, the difference between refined or not also plays a very large role. Broadly speaking, we can divide the olive oil into four types:
     1. refined oil is purified by an operation.
     2. Virgin olive oil is pressed cold and naturally contains little free acids. In order to be quadruple, olive oil must contain no more than 2% free fatty acids, which determine acidity. She is delicious in cold preparations but also suitable for baking and roasting because she only burns at about 215 °C.
     3. additional virgin olive oil is the result of the first pressing and the free fatty acid content shall not exceed 0.8%. It already oxidizes around 180 °C and is therefore only suitable for cold preparations. Moreover, it would be a pity to warm up such expensive oil that she will lose her characteristic taste.
     4. (regular) olive oil,which is often used for frying and roasting or frying, is usually a mixture of refined and virgin.
8. Rice oil This oil is less common in our Western cuisine. It is squeezed from the germs (and silver membranes) of the rice grains. As well as sunflower, rapeseed and olive oil, it is therefore a seed oil and they are known for their high content of unsaturated fatty acids. She is very light in color and has no pronounced taste.
   • Because it has a high smoke point (approx. 255 °C) she is suitable for frying or woking.
   • Like many vegetable oils, it contains the fat-soluble vitamin E and the silver membranes provide many other vitamins, minerals and also proteins.
   • 75% consists of unsaturated fats, about half of which are single and half multiple. Per 100 grams, it delivers about 33 grams of linoleic acid.
9. Coconut oil Is extracted from the dried flesh (called kopra) of the coconut. Above a temperature of 24 °C, the virgin oil (the unrefined) becomes liquid, underneath it takes on a solid shape and is called coconut fat. The refined melts at 35 °C. Coconut oil is processed in many products such as ice cream and biscuits and has also been popular in the kitchen in recent years.
   • Of all oil varieties (and even fat species), it contains the largest amount of saturated fats (82.5%), of which about half contain lauric acid (44.6%). As a result, the chemical structure remains intact when heated at high temperature. Ideal for woking and frying if you use the refined species. In the refined area, the smoke point is approximately 230 °C. In unrefined form, the oil oxidizes at about 177 °C.
   • Some sources claim that lauric acid is healthy because it is processed by our body in a different way from other saturated fatty acids, but there is no scientific evidence for this. For example, it would strengthen resistance, have a disinfectant effect and even help to lose weight. However, it has been scientifically shown that saturated fats increase cholesterol (both good HDL and the bad type of LDL) in the blood. Therefore, it is better to use coconut oil sparingly because high LDL values are associated with a higher risk of cardiovascular disease.
   • Because it is rich in saturated fatty acids it does not quickly become rancid and is long lasting.
10. Safflower oil Is extracted from the seeds of the safflower thistle, a plant akin to the artichoke and which is not grown in Europe. She has a pale yellow color and a fairly neutral taste.
    • Only suitable for cold preparations such as dressings or cold sauces.
    • Cold-pressed contains at least 70% of polyunsaturated fatty acids consisting almost entirely of linoleic acid (72 g per 100 g of oil).
11. Sesame oil is squeezed from raw or roasted sesame seeds, which instantly determines the color and taste. Raw seeds give a light-colored oil with a neutral taste, roasted make the oil light brown and nutty. It is an oil that is especially popular in Asia.
    • Suitable for cold and hot preparations, but it is recommended not to heat this oil for too long. For woks or deep-frying, you should use peanut oil.
12. Peanut oil or peanut oil Is extracted from peanuts, the underground tubers of the peanut plant that actually belong to the family of legumes. The oil is pale yellow and has a nutty taste.
    • The ideal oil to fry, stir, roast or fondue because it can be heated to 210 °C for a long time. So it remains stable for quite a long time at fairly high temperature.
    • Approximately 81% of unsaturated fatty acids consist of mainly single. The multiple (23%) are almost exclusively linoleic acid.
    • Is fairly long sustainable like all oil seus that are rich in monounsaturated fatty acids.

Some general opinions

• Store the oil in a cool (under 20 °C) dry place and respect the best before date. Some oils such as nut, rapeseed, flaxseed and wheat germ oil are even preferably stored in the refrigerator. Air, light and warmth are the enemy and that certainly applies to olive oil.
• From an ecological point of view, local oils such as flaxseed, rapeseed, sunflower and maize oil are preferred. Olive oil is healthy, but its 'water footprint' is quite high.
• Never heat oil above 180 °C when frying or roasting, even though its smoking point allows it. Over that temperature, too many breakdown products are released. Replacing frying oil in a timely manner, 6 to 8 baking is the maximum or less frequent use every 8 weeks, is also a golden board.
• Always read the label of the oil to check if it is suitable for hot preparations. The degree in which it is refined and its composition can vary from species to species, especially in rapeseed and sunflower oil.