Question About Preservatives

Natural preservatives are sugar, acid, and of course, salt.

Potassium can stop your heart in high enough doses. If you swallow half a can of Morton's No-Salt you could very easily die.

Kuan is right, enough potassium can kill you. In the old days, they used to inject clinical dogs with KCl (potassium chloride) to euthanize them. Sometimes they missed the vein and the dogs, even though they were heavily anethetized would yelp in pain.

Now they euthanize animals by putting them to sleep and then give them an overdose of barbiturates.

Anyway, the whole key to everything and anything in particular is "moderation".

Grace Slick once sang "Maybe preservatives are preserving you!".

Who knows for sure??!!

doc

Hi Shel,
Sorbate, sorbic acid, benzoate, benzoic acid, propionate, propionic acid and bisulfite usage levels in food as consumed are regulated by law in the US and Canada.

Propionic acid (and salt) are found in Swiss cheese and found to control certain undesirable bacteria in breads in particular called rope. Propionic acid derives from the breakdown of fats and found in human sweat.

Sorbate and sorbic acid are microbial controlling agent. They are effective against yeast and molds. They are found naturally in certain berries also as a preservative.

Benzoic acid, benzoate have similar effect then sorbate and are also found naturally in berries/plants (particularly cranberries which may explain why they do not rot in bog water).

Benzoic and sorbate work in highly acidic foods (i.e beverages). Propionic acid work is a more neutral pH (i.e breads). These chemicals do not kill microbes but prevent them from multiplying by affecting the membrane making machinery. There are found in nature.

There is FDA identified potential health hazard persistent in the beverage industry where benzoate and vitamin C are found together in an acid environment (fruit beverages, soft drink) it creates benzene a known carcinogen. The reaction is worst in diet products since sugar seems to slow the reaction.

The only really problematic chemical in the list above is Bisulfite because releases sulfite a known allergen and headache maker. It does not exist in nature per se. It's purpose is mostly to preserve the colour of the food like in wine or tomatoes. Sulfite oxidizes (capture oxygen) very easily so it protects fragile colours from fading or browning. Copious amounts (within limits) of sulfite are added to dried fruits and veggies (including sundried tomatoes) to preserve their colour when drying. Sulfites are also antimicrobial and anti fungal but do not affect yeast which is ideal for wine making.

(Erythorbate is used for meat where nitrite/nitrates are used but the chemistry gets complicated)

Luc H.

No (but yes),
If one follows the instructions on the label there would be no need for these ingredients since the acidity of the product should suffice to preserve it and give it a long shelf life.
(but yes, because the manufacturers protect their product image by maintaining the colour and preventing molds and yeast from sprouting in unsanitary or storage abuse situations from the consumer)

In a world where the customer is always right, as a process food manufacturer you make sure you cover all your bases.

Luc H.

That is a fair assessment Shel.

as for plastic bottles, air permeating inside the product is less of a problem then plastic chemical leaching in the food stuff or plastic degradation by the product. Plastic containers are a relatively new packaging material compared to metal canning and glass and like any packaging, they have their respected pros and cons. Preservatives are not added to products to mitigate packaging air permeation, at the very least, it is not a major reason.

The biggest problem for plastic packaging is the phenomenon called <paneling> where the sides of a plastic container is sucked inward of an unopened product. The phenomenon is not well understood but has something to do with product leaching in the plastic.

Luc H.