Formulation Tip: When Should You Use A Preservative In A Formula?

Formulation Tip: When Should You Use A Preservative In A Formula?

I decided to create a series of short articles that have tips in them. They will have the word ‘tip’ in their title, so they will be called ‘Formulation Tip’, ‘Aromatherapy Tip’, and so on. The tips will be on a variety of topics and they are answers to real questions I have been asked over the years. Some of this information is from the units of my Facebook group, while some tips will be compilations of posts that I have written from various sources (different groups, forums, my old eco blog, etc). I have edited and expanded my answers. I decided to create this series so that everyone would have access to this information, all in one place. I will still be writing other articles that are exclusive to Plant Alkemie’s website (my other articles will not be part of the ‘tip’ series. My other articles have not been posted elsewhere; they will be totally brand new content).

For more great information like this, or if you would like to ask me a plant question on formulation, DIY, aromatherapy, herbalism, eco living, or natural perfumery, then please visit Plant Alkemie’s group!

 When Should You Use A Preservative In A Formula?

Formulation Tip: Add a preservation to water based products!

Formulation Tip: Add a preservative to water based products!

For your safety and maximum shelf life, it is best to add a preservative when you are making a formulation that contains water or water rich ingredients. Products that contain water are called hydrous products. Water rich ingredients include water, hydrosols, and aloe. Examples of water rich products include creams, lotions, toners, and masks. Anytime you add water to a product, it can become contaminated with microbes within a matter of days, if the product is not preserved.

For home or personal use, some skin and hair care recipes that contain water rich ingredients can be made preservative free, but they need to be used up immediately or refrigerated and used up within a couple to a few days. For example, when you make a homemade fruit based mask, it is best to make only make enough for one use. Or if you make enough for 2-3 masks, then label and refrigerate it and use it up within 2-3 days. And use clean spoons or cosmetic spatulas when handling the mask.

For professional made, store bought products, ALL hydrous products should be made with a preservative.

Add an antioxidant to anhydrous products like oil based perfumes!

Add an antioxidant to anhydrous products like oil based perfumes!

If you don’t wish to use preservatives, then make anhydrous products. Anhydrous products are waterless products. A few examples include balms, oil based perfumes, facial oils, and body oils. Anhydrous products usually do not need a preservative. This does not mean they can’t become contaminated, but they are less likely to. To help the shelf life of an anhydrous product, I highly recommend adding an antioxidant, such as vitamin E or rosemary oil extract (note: vitamin E and rosemary oil extract are not preservatives).

In anhydrous products, you need to be careful when using them, to make sure that no water gets into them. If there is a possibility that water may get into an anhydrous product, it is best to add a preservative.

Resources: For more information or if you have questions about aromatherapy, herbalism, formulating, perfumery, and eco living, please join Plant Alkemie’s Facebook group and Plant Alkemie’s Facebook fan page.  And check out more articles on Plant Alkemie’s website: You may also leave questions about using preservatives in a formula in the comments of this article.

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  1. Excellent article and topic. Thank you Li.