chemistry question #2160



Sean M. North, a 30 year old male from Oregon City asks on June 29, 2004,

Q:

In a frying pan, when olive oil is added to butter and heated, according to some cookbooks and chefs, the butter solids do not burn. Why is this? Why is it that olive oil appears to be the only oil to have this effect on butter solids?

viewed 13361 times

the answer

Sean North answered on August 11, 2005, A:

[Editor: we tried it in the kitchen and found that if the oil was hot enough the butter solids browned as usual. The original questioner who was learning to be a chef at the time eventually answered his own question as follows.]

After experimentation I discovered that indeed the olive oil didn't prevent the butter solids(fat) from burning, but it did prolong the time it took for the butter solids(fat)to burn. Here's how it works. Start with oil(it doesn't have to be olive oil as was believed)in a hot pan. Add butter. As the butter melts the water in it floats to the top of the oil. Then the butter solids(fat) float on top of the water. The water acts as an insulating barrier between the hot oil and the butter solids(fat). As long as the water is there the butter solids don't brown. Eventually, the water does evaporate through boiling and the butter solids(fat) are exposed to enough heat to brown.

Add to or comment on this answer using the form below.
(required)
(required if you would like a response)
Note: All submissions are moderated prior to posting.
If you found this answer useful, please consider making a small donation to science.ca.