Beware of mold toxins in nuts

In addition to nougats and other typical sweets, Walnuts are a classic on Christmas tables. During after-meals or joint games, the nutcracker crackles regularly, the nuts are released from their shells, and the loot is offered in all its splendor.

The dried fruits form Essentially part of a healthy diet. Polyunsaturated fatty acids, vitamin E, antioxidant polyphenols, protein, and fiber make up a complete formula to maintain and enhance health. Studies show that they even reduce the risk of coronary heart disease.

Mycotoxins are carcinogenic

Health authorities in several European countries are looking into the problem of toxins that can be found in tasty nuts, but can also be found in grain-based products like whole wheat pasta and rolled oats.

Analyzes show that they are frequently attacked by two species of molds, Aspergillus flavus, ochraceus, niger and parasiticus, among others. These molds generate mycotoxins (mold toxins) called aflatoxins and ochratoxins.

aflatoxins and ochratoxins are generated in a warm and humid environment, which sometimes happens during harvest and during transport, but especially during storage.

Unlike what happens with microorganisms, high temperatures do not destroy molds during cooking, roasting or baking.

According to the Spanish Agency for Food Safety and Nutrition (AESAN), mycotoxins “can cause various adverse effects such as cancer induction and mutagenicity, as well as problems in the metabolism of estrogens, gastrointestinal or in the kidney”.

Some mycotoxins are also immunosuppressive and reduce resistance to infectious diseases, adds AESAN on its website.

50 European alerts

Last year there were about 50 European rapid alarms on the presence of aflotoxins, of which around 15% had reached the internal market of the Union. The main affected were pistachios (44%) and peanuts (33%), which came mainly from Turkey (46%) and Egypt (27%).

In ground almonds, on the other hand, aflatoxins were found in 68 percent of the samples examined, but only in three percent of the whole almonds. The Federal Office speculates that ground almonds might be more susceptible to mold penetration than unground kernels due to their larger surface area.

What can be done to avoid mycotoxins?

Consumers can protect themselves against mold toxins by storing food in a cool, dry, dark place. Shelled walnuts can be kept like this for up to a year. But this still does not offer a sufficient guarantee.

Unfortunately, mold toxins in nuts cannot be seen with the naked eye and have no particular taste.

But if you notice one dark coloration, an oily sheen, or an unpleasant odor (to rancid) when you open the nuts, you should not eat them.

If you notice an atypical, musty, or bitter taste, to be safe, don’t eat that nut and spit out whatever’s in your mouth.

Effective and ecological method against aflatoxins

Researchers have tried different methods to prevent the appearance of mycotoxins. Currently studies the application of Pichia anomala yeast to prevent its development in nuts and corn crops. This method is non-toxic and could even be used in organic farming.

The tests have been carried out in a pistachio plantation in California (United States). The experts sprayed some trees with Pichia anomala yeast and others did not. The results were clarifying, since the trees that were sprayed inhibited the frequency of the appearance of Aspergillus flavus in the pistachios by 97%, in comparison with the non-sprayed trees.

It has also proven effective in Harvested and stored nuts. In addition, it is confirmed that the use of yeast is very versatile, since its effectiveness in protecting other crops against at least six species of microorganisms that could alter characteristics such as flavor, texture, or flavor has also been verified. performance and food safety, including the pathogen Botrytis cinerea, which is thought to be responsible for gray mold on grapes.