Monday, December 1, 2014

Weekday Wonderings: More comments! Measuring small amounts and the anti-bacterial properties of oils

In this post, Question: Doubling, tripling, and dodecahexing!, Stephanie asks: I have chosen to weigh everything as I think it's the best way to do it according to all my research however, for ingredients that I have to suck out of a small bottle, can I use my syringe and assume that 1ml is equal to 1gr even if the viscosity differs from one ingredient to another ? I know that for instance, Vit E would weigh more than water but in such small batches, does it really impact the end result if I assume 1ml = 1gr ?

It really does matter. If we look at Vitamin E, it should be about 1 ml = 0.90 grams. So let's say you need 1 gram for a 100 gram batch of lotion to make sure that the product has the maximum anti-oxidizing power. Adding 1 ml means you don't have the maximum amount. Let's say we take that to a larger amount - we need 10 grams in 1000 grams. If we use 10 ml, we're only getting 9 grams. That's a big difference!

If we look at something like liquid Germall Plus, if the safe as used rate is 0.5%, and we go using more than that, could we be courting skin issues by using too much? Or are we asking for preservation problems if we use too little? If we want to use no more than 1% fragrance oil and we use 1ml, is that too much or too little? If we want to use glycerin, could that little bit extra make it feel sticky? It can mess up the emulsification of something if we aren't taking all the ingredients into account. It can cause your toner to have precipitation at the bottom because something didn't dissolve completely. It can take some ingredients from the "safe as used" to a slightly higher amount that could irritate skin or ruin the chemistry of your product.

In the grand scheme of things, using 0.1% more or less of something isn't the end of the world, but it can cause problems in the future. When you make a larger version of that lotion, it might not feel the same if you've been using less than the suggested amount of oils! Or it might not suds as well if you're using less surfactant than the recipe suggests.

Related posts:
How do I figure out the volume of a recipe?
Weight vs volume
How to figure out the volume of a recipe?
How do we convert from percentages to grams?
Measuring small amounts?

In this post, beeswax is not an emulsifier, Luna Love Farm writes: I am a massage therapist by trade and we use either sesame oil or coconut oil as our massage oil, both of which are naturally anti viral and anti bacterial. Would that not help with the contamination issue? If the water is suspended in the oil, then at least the outer circumference of that water droplet would become 'safe' by being in contact with the anti cootie properties of the oil? I am assuming that the fluid within the droplet would then become safe? 

I wanted to address the issue of our carrier or exotic oils and butters having anti-bacterial or anti-microbial properties. Although some of them may have low levels of those qualities and might work neat on the skin, they cannot preserve a lotion. (We see the same thing with honey...) When we're making products that contain water, we need to use a broad spectrum preservative suitable for that product.

What is a broad spectrum preservative? It means it it kills off bacteria, mould, yeast, and other fungi or a broad spectrum of beasties that might contaminate our productsThe preservatives we buy are called synergistic preservatives, which are combinations of preservatives intended to eliminate all the various contaminants we could see in our products. If you see a product that is just one preservative - for instance, sodium benzoate or phenoxyethanol - then it's not a broad spectrum preservative, and you'll have to combine it with something else to get all the beastie killing power you need!

A few studies about the anti-microbial nature of coconut oil
Anti-microbial effects of virgin coconut oil
Novel anti-bacterial effects of coconut oil
In vitro antimicrobial properties of coconut oil on candida species

Related posts:
Preservative section of the blog
Choosing a preservative
Are the preservatives in our ingredients enough to preserve the entire product?
If some essential oils are anti-microbial, why aren't we using them to preserve our products?

Join me tomorrow for more comments!

1 comment:

Birgit said...

Welcome back, Susan! So what would you say are the main problems that may arise from using too much or too many preservatives, essential oils our extracts at once? Let's say I'd accidentally add it twice? It would still be a small percentage of the product (as in general the recommended amount is a percentage of even a fraction of it) but now twice what's recommended. Or if I went really trigger happy with extracts and use ten different ones? Would I be looking at a possible skin irritation our is there more to look out for? I know you always ask what every ingredient brings, and ask if everything is necessary... Anyway my questions are mostly theoretical, just felt like this would be a good learning moment to understand more about max concentrations. And can there be harm from using e.g. green tea extract with aloe extract and carrot extract and oat extract all at once or would it just be wasteful? I know using several hydrosols (our replacing the whole water with them) is fine. How about replacing the whole oil with oil soluble extracts?
Sorry about so many questions, I have just been wondering about these topics for a while already.
Thanks and keep up the good work,