How much preservative can be in food?

Answer 1

Legally, there are very few limits to how much of an approved preservative can be placed in foods. the amount of a specific preservative varies with the type of food, and the manufacturer. Manufacturers usually use as little as they can, to save money. Ascorbic acid is a common cheap food preservative, and it's also "Vitamin C" as well as a source of "tartness", so a manufacturer can load up a food like a Hostess lemon pie or a drink like "Sunny D" with a ton of ascorbic acid and then advertise about how it "Supplies a full day's worth of Vitamin C!". Salt is also a preservative, and you can see how prevalent that is in our modern precessed food diet, from soda to baby food. Some of the more exotic preservatives like disodium EDTA or even formaldehyde are generally considered safe in small amounts, but there is continually a great deal of debate about the safety of food additives. A century ago, Mercury and lead were commonly added to candy (!) as colorants and preservatives, but are not allowed in any concentrations as additives in any food today. The Food and Drug Administration is responsible for setting legal limits on food additives, but that organization is always well behind the learning curve, and relay on research from private and public organizations to find out what chemicals in what amounts are safe.