Anti-oxidants & Essential OilsAnti-Oxidants are things like Vitamin E, rosemary extract and grapefruit seed extract, which prolong the natural shelf life of oils and fats. Their purpose is to interrupt the action of oxygene radicals which damage the integrity and function of various natural substances. They are useful in your product for two reasons. Not only will they help to prevent the natural degradation of the some of the raw ingredients in your formula, they will also help protect skin cells from similar damage, these effects include minimising age spots, imparting radiance to the skin and slowing down the formation of fine lines - so it could be said that they are anti-aging ingredients!
What they are NOT: Anti-Oxidants are not a preservative - they do not prevent the growth of bacteria in your product.
A note about Grapefruit Seed Extract This is an edible extract produced as a by product of the fruit juice industry, over which there has been quite a lot of controversy, in as much as quite often an undisclosed synthetic preservative is included at the point of manufacture. This means that sometimes when using this raw ingredient alone, your product will be protected against the growth of some bacteria. Many people believed, erroniously, that GSE was the first known 'natural preservative' whithout knowing that it contained a synthetic preservative, using the definition of preservative as something that will inhibit the growth of bacteria. Since this is an expensive ingredient to include I think it is important to find out as much as you can about it's manufacture before deciding to use it - or you could end up with a product that is over-protected... not necessarily a problem unless you are very particular about managing the levels of synthetic chemicals you use.
Essential Oils such as Tea Tree or Thyme have strong preservative qualities - that is to say they do inhibit the growth of bacteria, however the percentage required in order to protect a pot of cream for example is way too high for safe use on the skin - therefore their use as a preservative is not advised.
How do I Protect my Product?By making your own products YOU make the decision of which preservative to use and how much to put in. For example if you are including a fresh herbal tea or using flower water rather than distilled water you might choose to use a synthetic preservative at a slightly higher percentage than if your product is made with distilled water and includes tea tree essential oil.
Each formula should be assessed individually as to it's purpose, how long you need it to last and therefore which method of preservation you are going to use, if at all. For example if you are making up a small quantity of body butter for a girlie pamper evening the following day, you may decide not to use a preservative at all since the product will certainly last that long and will be entirely used up on the one occasion.
Documented instances of allergic reaction to synthetic preservatives are rare but you do need to take this possibility into consideration. Always follow the cleanliness guidelines when making your products.
Always follow the recommended percentage of use for the preservative and NEVER exceed it.
Always make your products in small batches that will be used fairly quickly. Never Double Dip!!