Feed Your Dog This Not That: Preservatives
Preservatives are, unfortunately, a critical component in most pet foods, especially the dry variety. A bag of dog food might not actually be purchased and opened by the consumer for 6-9 months or longer due to the industry’s long (slow) supply chain. As a result, dog foods must have relatively long shelf lives, often exceeding a year. The upshot of all of this is that dog foods, and in particular dry foods, must contain some form of preservatives to keep the food stable and edible for its entire anticipated shelf life.
Preservatives that are used in dog food are primarily meant to keep the food in the unopened bag (or other packaging) from going bad. The estimated shelf life of a food is indicated by the “use by” or “expiration” date that is stamped on the packaging. The idea is that as long as the package is unopened, the food will remain fresh up thought that date.
What many consumers don’t know is that once the package is opened, the food will begin to deteriorate nutritionally, no matter how far in the future the “use by” date is. As soon as the package is opened, the food will begin to lose potency, the fats will oxidize, and the food will spoil at a fairly rapid rate. Keep this in mind when choosing your dog’s bag size. Some pet experts, like Steve Brown, believe that an opened bag will only last about a week. Others take a more moderate view and suggest that an opened bag will last about 3 weeks before losing nutritional potency.
In any case, preservatives are an important part of a dog food recipe. And like all most types of ingredients, not all preservatives are created equal. Many preservatives are artificially created chemicals that really have no business being in dog food. Luckily, there are some healthier choices that can be used as preservatives that are natural and can even offer nutritional and taste benefits to the recipe. The table below provides some examples of preservatives that are OK to feed a dog, as well as some that are not at all appropriate (or even safe).
Preservatives in Dog Food
|Feed This||Not That|
|Mixed Tocopherols (Vitamin E)||Ethoxyquin – this is a pesticide and has been linked to cancer|
|Vitamin C, Acerola||Propylene glycol- this is an ingredient in anti-freeze|
|Rosemary (and extract)||BHA & BHT– both are suspected of being cancer causing.|
|Sage (and extract)||Tertiary Butylhydroquinone (TBHQ )- a form of butane used for varnish + resins|
|Clove (and extract)||Sodium Metabisulphite- a bleaching agent|