When adding a preservative to dog treats to extend their shelf-life, vitamin E as a preservative is the most popular choice for all-natural dog treats.
Vitamin E contains antioxidants that protect against the oxidation process that takes places in foods when fats and oils are exposed to air.
The higher the fat content of a food, the faster the oxidation process occurs. In other words, high-fat foods turn rancid quicker.
So, when dog treat manufacturers add the flavors and ingredients that dogs love, such as chicken broth, or bits of tuna, they also need to add a natural preservative if they want their treats to avoid spoiling before they even leave the shelf.
When adding vitamin E as a preservative to your dog treat recipes, add up to 10 drops to the liquid part of your ingredients before mixing your wet and dry ingredients together.
Vitamin E works as a natural preservative for a period of up to 12 months.
Studies show that a broad-spectrum vitamin E (multi-tocopherols) is more effective at combating free radicals than vitamin E containing only alpha tocopherol.
The oil is also used as a facial moisturizer due to its antioxidant properties.
You can find vitamin E oil at most organic or gourmet grocery stores.