Cis or Trans? FFC #18
Do you prefer butter or margarine?
To begin with, I think the taste of butter is superb. It’s creamy and nutty, even though it’s not made out of nuts. Margarine, to me, has always tasted somewhat wrong.
Then when I was at university I did a few food related courses, like nutrition and bromatology (the science of studying food). Something came to my attention, partly due to the nutritional issue itself, but mostly due to the fact that there didn’t seem to be any public alarm over it. Ok folks, I hope you don’t all think I’m bonkers because after my ode to chemistry last week, today’s post is not a pleasant chemistry one. The it that I want to write about is the issue of trans fatty acids.
How do trans fats affect our health? These types fats are not common in nature and our bodies are not able to assimilate nor metabolise them. They can even clog our arteries worse than cholesterol can…
Many types of vegetable fats are liquid at room temperature. Margarine, for example, is made out of these kinds of vegetable fats. But margarine needs to have a more solid texture for it to be margarine. Therefore these vegetable fats will undergo an industrial process, called hydrogenation, to make them harder and creamier. This process adds hydrogen atoms to the fatty acids of the vegetable oil, which will change their structure.
In nature, most fatty acids come in the form of cis-fatty acids. If you see the picture below you can see how the molecule is “bent”. The hydrogenation process makes many of them change to the trans configuration.
Imagine that you have two cups. You put cis-fatty acids in one of them and trans-fatty acids in the other one.
Due to the fact that the cis-fatty acids are bent, you will fit less molecules in the cup. There will be more room for these molecules to move around, and so they are liquid.
In the trans-fatty acid cup, you can fit more molecules and pack them tightly together because they are straighter, so they are more compact and solid.
Thus converting liquid vegetable fats into a more compact margarine is done by hydrogenation. Many other processed food use hydrogenation. Especially beware of all the diet foods that are low in fat but creamy. Many yogurts come to my mind here.
Then last month the FDA issued a press announcement regarding their concern about trans fats in processed food. (I thought: At long last!). It seems that the FDA has been working on making manufacturers cut back on trans fats. But manufacturers are really not there yet, so they need to declare the amount of trans fats on the labelling of their products so consumers can decide to purchase them or not. In my opinion, manufacturers may feel they “have their backs covered” this way and could just declare their trans amounts instead of eliminating them. Time will tell! The scope of the FDA covers the US, so other countries may not have these regulations in place. For more information, here are a few links:
Back to my initial question: butter or margarine? We all know butter is no angel either. Butter contains cholesterol and certain bad fats. But margarine also contains bad fats. I love the taste of butter, so butter is the winner for me.
Coincidentally last night we watched the movie Julie and Julia. It’s about Julie, a blogger that takes on a yearly challenge of blogging and cooking Julia Child’s cookbook in one year. Julia Child is played by Meryl Streep and as much as I adore her, this movie was too sweet and gooey for my liking – even though it did contain some powerful reach out for what you want to do messages. Funnily though, the movie also emphasised Julia’s love of butter.
Thank you for reading!