Sunday, January 31, 2010

E-mail question: Hydrogenated vegetable oil

More Cowbell poses this question...What timing! I was just looking at this on another site and wondering what the "hydrogenated vegetable oil" is. Do you know? Are we talking Crisco??? :) It seems to also have sweet almond oil, so what hydrogenated oil is so firm that it can incorporate that and still qualify as a butter? And why am I obsessing over this?

The short answer is yes, this product is similar to Crisco, but it probably isn't Crisco. The long answer...yes, this product is similar to Crisco, and here's how it's done!

When we hydrogenate an oil, we break the double bond in an unsaturated fatty acid and insert a hydrogen in its place. It is now a saturated fatty acid - it won't go rancid as quickly as the unsaturated fats and it's likely to be a thicker oil or butter because the fatty acids can lay side by side instead of being all kinky and more liquid.

If you took an oleic fatty acid molecule - C18:1, meaning it has 18 carbon atoms and 1 double bond - and hydrogenated it, we'd end up with stearic acid. As you can see, oleic acid has a kink in it, so it won't lie straight, so we get a more liquidy oil. Stearic acid lies straight, so you can pack them together more tightly, and it will be a thicker butter instead of an oil. You can do the same with any of the unsaturated fatty acids to produce a hydrogenated fatty acid that will pack together better and be a butter instead of an oil.

Here's the link to the larger post on hydrogenation. And here's the link on trans and cis formations in fatty acids.

If we look at the fatty acid profile of shea butter - for instance - we see it has 3 to 7% palmitic acid (C16), 35 to 45% stearic acid (C18), 40 to 55% oleic acid (C18:1), and 3 to 8% linoleic acid (C18:2). Although it is chock full of saturated fatty acids - 38% to 52%, it contains anywhere from 48% to 62% unsaturated fatty acids.

Take a look at sweet almond oil with a fatty acid profile containing 3 to 9% palmitic acid (C16), 2% palmitoleic acid (C16:1), 3% stearic acid (C18), 60 to 78% oleic acid (C18:1), 10 to 30% linoleic acid (C18:2), and 2% linolenic acid (C18:3). It already has between 8% and 14% hydrogenated fatty acids. If we hydrogenated just the oleic acid, that would make a very very hard butter now with 68% to 92% saturated fatty acids - it would contain more saturation than cocoa butter, which is a very very hard butter. So we wouldn't have to saturate a lot of the fatty acids to make it thick and buttery.

We saw a product like this in the green tea butter post - the INCI is hydrogenated vegetable oil, sweet almond oil, and green tea extract. Sweet almond is often chosen as it has a nice long shelf life and won't add any extra smell to the final product. The vegetable oil could be soybean, corn, or canola oil, amongst others. And of course, the extract. This is done to give us a butter for something that wouldn't naturally be a butter, like green tea extract.

As for why you are obsessing about this, I can only say I feel your pain! Things like this drive me crazy - that's why I started the blog! Hope I've managed to be some help here!

4 comments:

Lissa said...

Susan-
I bought an interesting product from Jen at LotionCrafters called LipidThix. It's powdered hygrogenated vegtable oil - an 80/20% (oil/80% LipidThix/20%) mix with any oil creates at hybrid butter. I love it with OO to make Olive butter.
Something fun to play with.
L

More Cowbell said...

Yes, it helped...but opened up many new cans of worms.

Like, how can they call, e.g., green tea extract, which is just ground up tea leaves in this case, or Camellia sinensis leaves to be more or less exact, an extract? Isn't an extract supposed to be something taken from the plant by "extraction," i.e., distillation, pressing, infusion etc.? it seems like a cup of green tea is much more an "extract" in the technical meaning of the word than are the ground up leaves from which the cup of tea was made.

Or is this just marketing-speak and not regulated by labelling laws?

Gad, what a nudge! :) But really, I just have to wonder...and you are so good about answering.

And about that More Cowbell...(there was a sale on ellipses)no one was more surprised than I was when that popped up. Heh. Long story.

Susan Barclay-Nichols said...

I was thinking about this when I wrote the posts on rosemary extract (coming up Tuesday, February 2) - why couldn't I just use the ground rosemary in the spice cupboard? (The smell, mainly.) The rosemary extract is processed in some way to remove the colour or scent or oils, so they can call it an extract instead of a spice or "ground up leaves". Most of the extracts we use are modified in some way - removing something awesome they want to use for something else, removing the oily part to make it more water soluble, removing smells, and so on - so I think that's how they justify it!

More Cowbell said...

Thanks, Susan! But, see, now, I'd like the smell. And boy do I have rosemary.

Thanks, Lissa, too for the pointer to LipidThix. The Herbarie has their own proprietary brand called Vegethix. I'm kind of attached to The Herbarie. :)