Wednesday, May 12, 2010

Yuk, that doesn't belong in my food!

As a continuation from yesterday, in regards to vegetable oil, How do they get all that vegetable oil out of all those soybeans and corn kernels and rapeseeds?

If you are like me and assume the best, you would have visions of the seeds all being ground up and pressed to extract the oil, probably on some contraption in a factory that looks very much like a Dickens novel. Almost like Oliver Twist was sitting in the employee break room. I don't have a scientific mind or any scientific experience, so my solutions to problems are somewhat simplistic.

Well as it turns out, pressing through a machine called an expeller is one way of extracting oil. But as you'd guessed, it recovers only so much oil. The leftover waste of crushed up seed pulp still has a lot of oil into. So what the vast majority of manufacturers do is use a solvent made of a gasoline byproduct called Hexane (C6H14) to extract the oil. The process of using a solvent is much cheaper and more efficient than pressing the oils.
Hexane is a colorless liquid that evaporates pretty easily because of it's low boiling point (50-70 degrees Celsius). And if I am reading these websites correctly, it is the part of gasoline that smells like gasoline, because it is one of the first compounds in the gas to evaporate. Use of Hexane as a solvent has been deemed safe because the hexane is largely nonreactive with the food with which it is coming in contact. Hexane is also used in glues for shoes, leather products, roofing and textile manufacturing.

The seeds are crushed and then flaked into very small particles. That mash is combined with hexane and heated with steam. This process extracts all the oil in an oil and hexane solution.
That solution is taken away and the hexane is removed through an heated evaporation process. The oil is further refined and cleaned while the hexane is reused in another batch of mash.
Most of the hexane that is lost remains in the mash, or the leftover fiber and pulp of whatever seed was crushed in the first place. I didn't do a lot of research as to what happens to the leftover mash. I don't want to extrapolate on where it goes, I would bet that it is used in some industrial function.

I firmly believe that natural products are the way to go for my family. I don't want to eat anything that has had harsh chemicals used to make it. I also don't like the idea that it required me several days of research to find out how this food product ends up in my belly. Foods like this are faceless. You don't know who grew them, how they were processed or much else. These are foods that our great grandparents weren't cooking with a whole lot. Butter and Lard were much easier to render. And although olive oils and others have been made for centuries, Olives were not such a plentiful crop on the cold east coast of the colonial United States. Our food culture simply did not include olive oil because it wasn't available.

Today, I am looking for alternative oils. And there are alternatives. While I'd like to stay away from Canola, I understand that not everyone will find fault with it's GMO heritage. I have decided that I'd like to try peanut oil. It has a high smoke point and it is a food that in it's most basic state is edible. Cottonseeds, not so much.

Please read my blog tomorrow as I look for a peanut oil that is made without hexane solvents...


Hexane. Wikipedia, The Free Encyclopedia. 9 May, 2010.
Vegetable Oil Processing. Environmental Protection Agency. 10 May, 2010


  1. Christa,
    Just read all of your posts and I totally love this!! Just be careful what you say, the veggie libel laws could come after you!!!

    In addition to Michael Pollan, I would also recommend "The China Study" by Colin Campbell. I also just took a weeklong immersion in cooking and nutrition at The Kripalu Yoga Center with the most amazing nutritionist in the world, John Bagnulo. If you can manage the time I highly recommend it. If not, they post a lot of recipes on the website, Keep writing, this is great!!

  2. I'm loving your blog. You and your family will be better off because of your wonderful experiment (although thing 1 may challenge that notion at times :) )

    Have you tried Coconut oil yet??? It's delicious and so incredibly good for you. Check out this link about it!