When oil is used for cooking, the structure of its forming fat molecules changes in different ways. This happens when oil is used for frying, when it is used just to grease the cooking pan, or when it is one of the ingredients of the product to be cooked (regardless of its industrial or home-made origin).
In order to set up the correct rotation dietary plan, we should always avoid industrial foods as these contain cooked fats and we should also choose to cook any dish without oils, by just adding water every now and then during the preparation (in this way, the cooking temperature does not reach 100°C and all the natural fats of the food are preserved). The preferred type of oil can be added afterwards, raw, at the end of the cooking process.
These simple instructions are going to give a more homogenous taste to the dish, while retaining its nutritional properties and the taste of the oil used (for example, the Omega-3 fatty acids contained in fish are much more preserved if the cooking process is more gentle and at lower temperatures).
Every type of oil reacts differently to physical agents (including heat) in relation to the different content in antioxidants.
The best types of oil able to keep their peculiar properties at high temperatures are extra-virgin olive oil and peanut oil (the latter is the best of all, being able to resist well at higher temperatures compared to other oils). These two types of oil should always be “cold-pressed”: this way, we can be sure that those structural modifications caused by cooking did not happen during product extraction. Moreover, extra-virgin olive oil and peanut oil are to be chosen during free diet days, or when “greasing” the cooking pan is absolutely unavoidable.
It is always advisable to limit the cooking time with oils and the cooking temperature should be the lowest possible.
List of foods containing nickel, to avoid on a rotational basis according to the instructions given
- Any pre-cooked food containing oils: the cooking process causes chemical alterations similar to the hydrogenation process used to produce margarine. Even when the label does list the presence of “natural oil” or “non-hydrogenated oil” among the ingredients, we cannot be certain of the final structure of the composing fatty acids after cooking.
- Home-made fried dishes or recipes requiring the addition of oil before cooking: this includes the procedure of greasing the baking tray or the frying pan, which is a typical habit when preparing pizza or roasting potatoes, independently from the quality of the oils chosen.
- Industrial products containing vegetable oils or margarine: with very few exceptions, any bagged product (crackers, biscuits, bread sticks, crisps, roasted peanuts) and many special types of bread (seasoned, with oil, wholemeal, toasted, focaccia, croutons) contain cooked/modified vegetable oils. This is also true for chocolate bars (with the exception of a few “dark” products of good quality), ice-cream, candies, industrial patisserie products (every sweet snacks, biscuits, brioches and small pastries), stock cubes (including vegetable ones), some types of fruit jam, fast-food products and fried industrial products.
Caution: the reactivity to cooked oils is detected by measuring types of IgG immunoglobulins also produced in response to certain oily seeds. People allergic to almonds, peanuts, walnuts or other types of seeds should refrain from eating them (unless these are already part of their customary diet) even if this is not explicitly indicated in the dietary suggestions listed in the medical report.