For twenty-four years I have participated in various scientific contributions and lines of research, but in recent years I have worked mainly on two major lines of research. On the one hand, in the field of food security, analyzing which oxides are generated in food, how and why they are generated, etc. On the other hand, we have developed functional meats.

Sterols are a group of food fat compounds. One of them is cholesterol in animal foods. Cholesterol has several important physiological functions, but at the same time, too much cholesterol is harmful to health. Plant foods contain phytosterols. In principle, these do not play a special nutritional role, but in recent years they have aroused great attention for their healthy effects.

Sterols have several unsaturations that can be easily oxidized. As a result of this oxidation various molecules are generated that can cause safety problems.

More than 40 years ago we learned that cholesterol is easily oxidized and since then more than 70 cholesterol oxides have been identified, of which 8 appear in food and the body can absorb between 10 and 40%.

In the last 30 years it has been detected that these compounds can have different toxic effects in the body. Perhaps one of the most important or known is that they influence the processes of atherosclerosis. Cholesterol oxides form an atheroma plaque that narrows blood vessels to cause deaths in patients with thrombi and cardiovascular disease.

Therefore, it is essential to control the amount of cholesterol oxides present in food from the point of view of food safety. However, there is not much data on the amount of cholesterol oxides present in foods. And its determination is not an easy task for several reasons. On the one hand, they are in very low concentrations, per million. Therefore, it must be a method of great sensitivity. On the other hand, all structures have a similar polarity, so their determination requires a high resolution analytical method. In addition, being mixed with other compounds of similar origin, its cleaning is essential. In turn, it is a series of unstable oxides that transform into diverse compounds. All of them make it difficult to study oxides.

Three factors are involved in the formation of cholesterol oxides present in food: origin of food, industrial or culinary processing that supports food and storage conditions.

As for the origin of the food, they must be foods of animal origin and it seems that the higher the unsaturation, that is, the richer the food in unsaturated fatty acids, especially in polyunsaturated, the easier the formation of oxides. As for processing, among other things, dehydration, sterilization and, above all, irradiation (even if the food temperature does not increase) facilitate the synthesis of these products.

As for cooking preparations, in general, all temperature increase technologies mean an increase in the concentration of cholesterol oxides relative to raw food. This increase in oxides has been observed in prepared foods at 85°C. In this sense, our research team has analyzed meat and fish made in various ways, and has found that cholesterol oxides are more easily formed in the microwave than fried or roasted foods. This may be because the microwave has another heating mechanism. It has also been observed that vacuum packaging technology for storing or storing food reduces the formation of these oxides.

But you have to have a clear thing. Although it is known that cholesterol oxides form in foods and that, in general, cooked foods contain more cholesterol oxide than raw foods, it is not a matter of extreme gravity. In fact, the amount of cholesterol oxides present in food is very low and usually does not reach potentially harmful concentrations for health.

Yes, it is. While we were studying samples of fresh and frozen prawns, we saw that in fresh prawns the concentrations of cholesterol oxides were higher. This means that from an oxidative point of view frozen prawns have better conditions than fresh prawns. The truth is that if certain foods are properly frozen and stored, their quality is not lost at all.

Phytosterols are functional components from the point of view of European Union food legislation. Why? Several studies have shown that these compounds are able to reduce blood cholesterol levels, especially because they prevent cholesterol absorption. It is an important fact. Currently, people with a high level of cholesterol are advised to take phytosterols or products rich in phytosterols.

Less research in the formation of phytosterol oxides. That is, the toxic effects of phytosterol oxides have been studied much less than those of cholesterol oxides. There are limitations to your research. On the one hand, its blood concentration is lower, so its possible toxic effect seems less significant. On the other hand, the determination of phytosterol oxides is further complicated. In fact, there are many phytoesters and by oxidizing each of them several compounds are formed. All of these compounds have a similar structure, so their identification and separation is not an easy task. In addition, phytosterol oxide patterns do not exist on the market. Therefore, if the laboratory wants to study phytosterol oxides, they must first be synthesized.

When analyzing a product rich in phytosterols, such as margarine, it has been observed that it is also rich in phytosterol oxides. So while we don't know much about the toxic effects they can cause, and although the body probably absorbs much less than cholesterol oxides, it's worth taking them into account and controlling them. I think there is still much to be done in this area.

On the one hand, we have developed at the pilot plant level several meats with less salt, such as chorizo. As is known, excessive salt intake negatively affects health. However, in some products, including these meat derivatives, it is very difficult to remove salt. Salt is fundamental from the point of view of product stability, as it controls the growth of microorganisms. Also, since salt gives the food the salinity characteristic of these products, it is very important from the sensory point of view.

In my opinion, one of the most successful formulations obtained for partial substitution of sodium chloride (common salt) is a mixture of salts containing ascorbate and calcium. In fact, ascorbic acid is antioxidant and, on the other hand, calcium is an important component from the nutritional and health point of view.

Another aspect to consider in these products are fats. In general, meat products contain huge amounts of fat, especially saturated fatty acids. In addition, the elimination of fat from these products is not an easy task, since its sensory quality is affected. However, it is possible to change the type of fatty acid to a healthier one. For this reason, we have carried out different research and have replaced the bacon of these products with an emulsion made with soy proteins, water and oil (vegetable oil, fish and algae).

The product produced with this new formulation contains the same amount of fat but is healthier in terms of the type of fat as the original product. In addition, it adapts more easily to the criteria that currently prevail in food. It is now recommended to consume monounsaturated and polyunsaturated fatty acids – especially long-chain omega-3 fats, and reduce the amount of saturated fats we eat. The products mentioned above are beneficial in this regard.

I didn't want to end the conversation before giving a small explanation: "You have to have a clear thing. There has never been so much food security. However, there is always danger."