Why are bananas and almonds radioactive


Kleefeldt, Stanojlovic


The Sigmaringen Chemical and Veterinary Investigation Office examines nuts and nuts products centrally for Baden-Württemberg. Nuts (also nuts) is the common collective name for types of fruit whose kernels are surrounded by a hard, mostly woody skin. These are nuts and kernels that are suitable for human consumption. In a priority program, nut-fruit mixes - so-called trail mix - and nut kernel mixes were examined.

Trail mix is ​​a classic among snacks. Trail mix consists of dried fruits, mostly raisins (sultanas) and unsalted nuts, such as peanuts, Brazil nuts, walnuts, hazelnuts, cashews and almonds. In addition to these classic products, nut kernel mixes with tropical fruits such as dried mangoes and dried papaya, but also with coconut flakes, banana chips and cranberries are increasingly being offered.

Where does the name "Studentenfutter" come from?

It is reported that almonds were used as a home remedy for hangover in the 17th century. Since the students were said to like to party even then, they are said to have nibbled on a mixture of almonds and raisins in order to cope better with the consequences of the copious consumption of alcohol. Another thesis is that the name could have resulted from an alleged concentration-promoting effect on the learners.

The average consumption of nuts and nut mixes in Germany is only around 2 g per day for adults [1]. For years, nuts have had the image of fattening food, as they contain between 50 and 75% fat. However, the fatty acid composition is decisive. Nuts contain nutritionally valuable monounsaturated and polyunsaturated fatty acids, the proportion of saturated fatty acids is rather low. For example, walnuts and Brazil nuts contain significant amounts of important omega-3 and omega-6 fatty acids, which are among the polyunsaturated fatty acids that the human body cannot produce itself.
In addition to the fatty acid composition, other valuable ingredients such as vitamins, minerals and trace elements, secondary plant ingredients and fiber play an important role in the nutritionally positive properties of nuts. For these reasons, nuts are a valuable part of the diet.


 walnut almond
Brazil nutPecan nut
Calorific value (kcal)
Fat (g)63544262736772
several of them
unsaturated fatty acids (g)
Dietary fiber (g)6143811710
Protein (g)141918128149
Phosphorus (mg)
Magnesium (mg)
Potassium (mg)
Calcium (mg)







Vitamin E (mg)6260,826*83

* = not specified

The composition of nut-fruit mixes or nut kernel mixes is not regulated by law in Germany. There is no special regulation, such as a "trail mix regulation", which prescribes minimum quantities or certain ingredients.


Each manufacturer can decide for himself how the trail mix or nut kernel mixes are composed in detail. However, food must be safe under EU law. Regulation 178/2002 regulates throughout the EU that food must be suitable for consumption by the end consumer and that it must not cause any health impairment or damage. The food business operator is fundamentally responsible for the safety of his products. The control of compliance with these regulations is, among other things, the task of the official food control.

To assess the current situation, a total of 36 samples of trail mix and nut mixes were examined at the Chemical and Veterinary Investigation Office in Sigmaringen. At least 15 samples (= 42%) were objectionable.

Examination for toxic ingredients

Both trail mixes and nut kernel mixes usually contain sweet almonds. In four samples, the toxin hydrocyanic acid (HCN) was found in the almonds, sometimes in very high amounts. The peak value was 120.9 mg hydrogen cyanide per kg almonds.
Hydrocyanic acid (cyanide) is found in the kernels of bitter apricots, cherries or peaches as well as in bitter almonds. The natural ingredient is released from cyanogenic glycosides such as amygdalin through enzymatic hydrolysis, e.g. when chewing or during the digestion process of the almond kernels.

                                                                enzymatic cleavage

Amygdalin itself is relatively less toxic as long as no hydrogen cyanide is released. Hydrocyanic acid, on the other hand, is a toxin that can cause poisoning or even death in humans. The lowest fatal oral dose in humans is given for a single intake as 0.5 mg hydrogen cyanide per kg body weight[3]. Hydrocyanic acid blocks cell respiration. Typical symptoms of cyanide poisoning are dizziness, vomiting, headache or shortness of breath.
Sweet almonds are free from amygdalin and can be enjoyed without hesitation. However, some sweet almond trees occasionally provide individual almonds that just contain noticeable amounts of the bitter substance. Bitter almonds, on the other hand, contain around three to five percent amygdalin. The substance is thus a naturally occurring but toxicologically undesirable substance. Bitter almonds are therefore not suitable for human consumption.
Mixing with individual bitter almonds is believed to be the cause of the high levels. 4 samples (11% of the samples examined) with high levels of hydrogen cyanide were judged to be unsafe foods or harmful to health.


Investigation of the valuable components

The so-called Quid (Quantitative Ingredients Declaration) ensures that the consumer knows the proportion of certain ingredients if this ingredient is part of the sales description or is particularly highlighted by pictures or words on the packaging. The percentage quantities are then usually given in the list of ingredients. The purpose of this provision is to enable the consumer to choose between products with the same sales description.

The verification of quantity information primarily serves to protect against consumer deception. The overriding principle is that information must be correct and not likely to mislead the consumer. For 6 products (17% of the samples) it was found that the percentages given on the packaging did not correspond to the actual contents of the packs tested. In several cases, the specified amount of cashew nuts was clearly undercut. For example, “15%” was advertised on the packaging; it actually contained a modest 8.4%, which was just 56% of the declared target. In other cases, not 16%, as stated, but only 9% candied papaya cubes in the trail mix. They also saved on banana chips. Only 13% were found in a sample, actually 19% should have been included. They didn't skimp on raisins for this. In individual cases, trail mix contained 37% raisins, although 31% had been declared. There were not enough cashews and almonds in the nut mix, but the proportion of peanuts was significantly higher than stated.
The valuable ingredients were rather underrepresented, while cheaper ingredients were used as filling material.


Review of taste and appearance

Overall, no errors were found in the sensory test. Both in terms of taste and appearance, the products tested impressed with their typical aroma and good quality. A nut kernel mixture was the only exception, traces of pests eating were found on the hazelnuts.


Checking the labeling

Checking compliance with labeling regulations is another important area of ​​responsibility of official food control. For example, it is checked whether the mandatory information required by food law is correct or whether voluntary advertising statements are correct or whether they are likely to arouse misconceptions among consumers. Among other things, non-approved nutrition-related statements, incorrect nutritional information or contradicting product names were objectionable. Altogether, in seven cases (19%) of the 36 samples examined, violations of labeling were found.



[1] Max Rubner Institute Federal Research Institute for Nutrition and Food,
National Consumption Study II on Food Consumption 2009
[2] Souci / specialist / herb: nutritional tables 7th edition 2008
[3] The EFSA (European Food Safety Authority) Journal (2004), 105, pages 1-28






Article first published on November 3rd, 2016