Saturday, November 16, 2013

Weekend Wonderings: Covering up medicinal hydrosol smells? How long does Vitamin E extend a shelf life? What is rosemary extract - anti-oxidant or preservative?

In this post, Making a toner for the oily skin type, Lynda asks: I made the toner recipe above and I don't like the way it smells. I love the scent of fresh rosemary, but the brand new rosemary hydrosol I opened to make this has a medicine smell about it . I find that most hydrosols have that bit of a medicine smell to them. Is this normal? Alas, I don't really like the scent of witch hazel either. Any ideas about a good essential oil to add here that might freshen things up? 

I'm with you! Those medicinal smells are normal (although I find chamomile a bit musty smelling), but some of us need to cover them up with something else. What works? You can use a small amount of an essential oil - maybe 0.5% - and make sure that this will work on your face. Tea tree might be a good choice, but that's kind of medicinal as well. You don't want anything that might be minty - tingling might not be a good idea on lips and near eyes - and I don't suggest anything too earthy. You might be smelling this all day, so consider what you really like. You could do lavender essential oil - although I wouldn't like that - or consider something like vanilla essential oil or extract.

If you aren't adverse to fragrance oils, I found that a light scent, like green tea or cucumber, at 0.5% can chase the medicinal smells away and it isn't horrible on your face all day.

Anyone have any great suggestions? I admit I'm not that fond of most of the smells of essential oils as they're either too floral or too earthy! 

In this Weekend Wondering post, Stacy asks: I have a question that I can't seem to find an answer to: What is the exact (or approximate) time frame that Vitamin E extends the shelf life of an anhydrous product? Days? Months? 

As I mention in this post on anti-oxidants (found in the FAQ), there are just too many variables to figure out the shelf life of a product beyond an estimate, and that gets even more complicated with anti-oxidants.

How old is the oil when you use it? How are you storing the product? What's the temperature? Opaque or clear container? These are things that can speed up or slow down oxidation, so they will have an effect on your product.

If you store a lotion bar with a shelf life of six months in your bathroom where the heat is on and people are taking a warm, steamy showers twice a day, you'll have a shorter shelf life than one left in my unheated workshop through the winter. Add some Vitamin E to the product and it'll last longer, but we simply don't know how much longer.

Based on my own experience, I have found that my lotions avoid rancidity much longer than I would expect. For instance, the lotions I made for last Christmas smell as fresh as the day I made them, and they should have had a life span of less than a year. (I know anecdotes don't make up data, so please take this as an example.)

In this post, Lotions: a basic recipe, Anonymous asks: What do you think of rosemary extract, or ROE, as a preservative?

I don't because it isn't. Rosemary extract is an anti-oxidant, something that retards rancidity in our oils and oil soluble ingredients. A preservative is something that prevents contamination of our water containing products by things like bacteria or yeast.

Related posts:
Rosemary essential oil
Preservative section of the blog
A closer look at anti-oxidants
Rancidity: A primer
Mechanisms of rancidity

I better run! International Gaming Day @ the library beckons!

1 comment:

Lise M Andersen said...

Hi Susan - As to the medicinal smell of rosemary_ this is true. The essential oil and hydrosol can seem quite medicinal smelling on its own. I would suggest adding lavender as this blends well with rosemary and will 'dampen' the medicinal effect.

Maybe doing an alternative mix of hydrosols altogether is worth a try. For oily skin, I would be looking at lavender and rose hydrosols in a mix. (this makes for a lovely, fresh-scent). Also, lemon balm hydrosol mixed with verbena hydrosol is a lovely, fresh, green-smelling combination and oily-skin friendly.