«Nitrites and nitrates
Use limits
Nitrites can be added to foods up to a maximum dose of 150 milligrams per kilo and cannot exceed a residual limit of 50 mg / kg at the time of sale.
Regarding the maximum values for nitrates and nitrites in drinking water these are respectively 50 micrograms / l for nitrates and 0.5 micrograms / l for nitrites. A quantity much lower than that allowed in food storage (about 5000 times lower for nitrates and 100, 000 times lower for nitrites)
In mineral waters two different dosage limits are instead provided:
- 45 mg / L in ordinary mineral waters
- 10 mg / L in those intended for childhood.
- 0.02 mg / L of nitrites for both categories
Why are they used?
Nitrates and nitrites:
- maintain and enhance the red color of the meat
- they improve its shelf life and aroma
- they have an antimicrobial and antiseptic action (especially against botulinum)
- In the case of excessive development of bacteria, nitrates are transformed into nitrites which in turn eliminate excess microorganisms and increase storage time
How to recognize them in the food label?
Usually on food labels their name is given in full; in some cases, however, the manufacturer prefers to use European abbreviations:
- the letters E249 E250 identify the nitrites
- the letters E251 E252 identify the nitrates
- The term ascorbic acid identifies vitamin C which can also be replaced by the abbreviation E301
- the term citric acid emphasizes the presence of a substance contained in lemon juice (E 330) with properties similar to vitamin C
What precautions?
The precautions to be taken to defend against the negative effects of these substances are numerous:
the first, of course, is to reduce the consumption of products containing nitrites and nitrates. Avoiding these foods is not always easy, as these substances are present a little in all products (with rare exceptions). Once again, the food label comes to our aid, a real mine of information for the intelligent consumer. If the word appears between the ingredients:
- nitrites (E249 E250): it is good to avoid or at least limit their consumption;
- nitrates (E251 E252): should be consumed in moderation as they are less dangerous than the previous ones but not completely safe
- nitrates (E251 E252) in association with ascorbic acid (vit C) and citric acid: quite safe, thanks to the beneficial properties of vitamin C (antibacterial action, inhibitory action on nitrate transformation into nitrites).
Other useful tips for the consumer:
- avoid heating foods containing nitrates, since heat facilitates their transformation into nitrites
- Since the bacteria present on the back of the tongue favor the transformation of nitrates into nitrites, it is good to maintain good oral hygiene, both before and after meals
- Since the storage times affect the concentration of nitrite, try to consume nitrate-based products in the short term
The same rules also apply to foods of plant origin:
- prefer seasonal vegetables, avoiding those grown in greenhouses;
- in the case of autonomous production: avoid chemical fertilizers and collect vegetables preferably in the evening
- eliminate the parts with the highest content of nitrates which, as we have seen, are stems, leaf ribs and external leaves
