Aflatoxins in nuts and dried fruits: A menace to health and nutrition
We have heard a lot about the benefits of nuts and dried fruits. They are delicious and enjoyable snacks that most people like. Most of the nuts are healthy to the heart, and dried fruits also carry the benefits of their original fruit, which means they mostly have antioxidants. However, something that most people don’t know about these healthy snacks is a harmful substance that might be in nuts and dried fruits, called Aflatoxins. Don’t worry, we are not going to frighten you with this subject, we only want you to be aware of this substance, but still, enjoy your healthy snacks.
What is Aflatoxins?
Aflatoxins are found all around the world in different foods. Certain kinds of fungi, which are poisonous, are responsible for this toxin production. Since the fungi can contaminate food crops, Aflatoxin is threatening to humans. Aflatoxins are mostly grown in warm and humid regions of the world. That’s why nuts are often affected by these fungi because they need a warm place to grow. Sometimes the drought, insect damage, and poor storage may improve the growth of this toxin in different foods. Therefore, Aflatoxins may affect food crops even after harvesting. That also happens in regions with high temperatures during the process of storing foods.
Tree nuts and peanuts are among the edibles that are highly in danger of contamination with aflatoxins. They may be affected before harvesting. The post-harvesting affected foods are mostly coffee, rice, and spices.
There are more than 14 types of Aflatoxins in the world. However, only four types are dangerous to humans and animals. They are referred to as B1, B2, G1, and G2. Foods are checked for these types of aflatoxins before going to the market. However, aflatoxin contamination in foods is not zero, but there are some rules and regulations for them. For example, the maximum acceptable level of aflatoxins in all foods is normally 20 parts per billion (which is indicated by ppb). This amount is usually below a dangerous level. But some foods and nuts should even have fewer aflatoxins level than the mentioned number to be accepted in the market.
Aflatoxins in nuts
Generally, peanuts are on top of the list of nuts that are at a high risk of aflatoxin contamination. One kilogram of peanuts is allowed to contain only 4 ppb (4 mcg/kg) of total aflatoxin and 2 ppb of aflatoxin B1.
Although peanuts may have the highest level of aflatoxins, you can easily control them by visually checking. The moldy-looking, discoloration, or shriveled specimens show that the peanuts are infected. Therefore, control peanuts for these signs and avoid buying any infected peanuts on the market to minimize your exposure to aflatoxins. Moreover, to make sure that you are consuming the healthiest peanut butter, you can buy high-quality peanuts on the market and make peanut butter at home. Also remember to store peanuts and peanut butter in a dark and cool place to keep them healthy and prevent them from becoming spoiled.
After peanuts, pistachios are at a high risk of contamination by aflatoxin B1. That’s why it’s important for the wholesale pistachio buyers to purchase this expensive nut from the well-known and best companies in the business. Pistachios that grow under the best conditions have the highest quality and are less prone to be affected by aflatoxins. On the other hand, it’s important for customers to buy this delicious and crunchy nut from the best shops on the market. Pistachio sellers should keep these nuts in cool and dark stores in the best conditions to keep the quality of this nut and avoid any mold or infection.
The acceptable level of aflatoxins in pistachios is 10 ppb of total aflatoxins and 8 ppb of aflatoxin B1. Since this type of aflatoxin is more dangerous than other types, the FDA and European Commission have set separate limits for aflatoxin B1 in different foods and nuts.
Aflatoxin exposure is visible in shelled pistachios or any other shelled nuts because it mostly affects their color. Thus, any discoloration on pistachio kernels indicates that the pistachios are infected and not in good condition.
Pistachios have many benefits for the body. They are high in protein, a great nut for diabetes, heart-healthy, a preferable snack for athletes. Moreover, pistachios are healthy choice for people who want to follow a keto diet.
Besides their numerous health benefits, Brazil nuts are also prone to aflatoxins infection. It may negate some of the beneficial effects of selenium in this nut. Selenium can help the body become more resistant to different types of cancer, and Brazil nuts are high in this substance. Therefore, to make sure that the Brazil nuts you are consuming are healthy and beneficial, look for undamaged and properly stored nuts. Like other nuts, any discoloration and mold-looking on Brazil nuts can show the contamination of aflatoxins. Furthermore, studies show that in-shell Brazil nuts might have lower levels of aflatoxins than the shelled ones.
Research done on nuts indicates that cashews are less prone to aflatoxins. However, it doesn’t mean that the amount of aflatoxins in this nut is zero, but that’s much lower than other nuts, including Brazil nuts, walnuts, peanuts, or pistachios. But you still need to buy high-quality cashews without any damage or discolorations. One kilogram of cashew nuts also can contain only 4 ppb of total aflatoxins and 2 ppb of aflatoxin B1.
Although all the nuts may be affected by these fungi, the mentioned nuts are most prone to aflatoxin contamination. You can visually check all types of nuts, especially the shelled ones, to find out if they are infected or not.
Aflatoxins in dried fruits
Since fruits are among botanicals that are at the risk of aflatoxins contamination, dried fruits might face this problem too. Dried figs are highly prone to this condition. To find out if dried figs are exposed to this toxin, check their color under ultraviolet light. If it is bright greenish-yellow fluorescence, this dried fig has aflatoxins, and it’s better to avoid eating it. Some studies show aflatoxins in dried plums (prunes), dates, raisins, apricots, and quince. Like nuts, there is a maximum permitted level of total aflatoxins in dried fruits too, which is 4 ppb in one kilogram.
The risks of Aflatoxins
All the foods and nuts on the markets are checked for harmful types of aflatoxins. They can have a minimum amount of aflatoxins that are not hazardous for the human body. That’s because large doses of aflatoxins are dangerous and may lead to:
- Poisoning (called Aflatoxicosis), which is life threatening
- Liver damage or liver cancer, especially for people who may have conditions such as Hepatitis B infection.
- Vomiting, abdominal pain and nausea are other side effects of consuming high doses of aflatoxins.
- Some people might even go on coma if they consume high amount of aflatoxins.
How to minimize Aflatoxin risks?
First of all, the farmers and companies are highly responsible for monitoring their food crops to prevent them from the impacts of this toxin. However, this substance can’t be completely removed from our food chain. That’s why Food authorities in different countries, like FDA in the US, have considered a maximum acceptable amount of aflatoxins in different foods to make sure they are not harmful to the human body. But there are still things you can do to reduce the risk of aflatoxins contamination:
- Buy nuts and dried fruits from trusted brands that comply to food regulations.
- Avoid storing nuts and dried fruits in conditions that may affect their quality. Moisture, mechanical or insect damage, and temperature are the things that might influence contamination and toxin production.
- Visually check the nuts you want to buy to ensure they don’t have discoloration or any other problems.
Aflatoxin check in trade
Since there are rules and regulations for aflatoxin-safe products in different countries, it’s easy to import healthy nuts and dried fruits from other countries. Import and export controls improve the trade between countries. Today every food that is imported or exported are checked before going to the market. The provider of foods also needs to show the certificates that guarantee the safety of the foods. Therefore, there is no concern about nuts or other foods being contaminated with a high amount of aflatoxins.
Aflatoxins are dangerous to human health. Consuming this toxin may lead to different health problems, such as liver cancer. Since all the foods, nuts, and fruits are checked for this substance, it is very rare for anyone to be poisoned by this toxin. Moreover, it’s also easy to find out if a nut has aflatoxin or not because this toxin changes the color of nuts in the first step. Therefore, you may recognize the healthy and unhealthy nuts from each other just by looking at their appearance. You don’t need to be concerned about this toxin, knowing how to minimize the risk of aflatoxin contamination is enough for consumers.