Thursday, 22 February 2007

Vaquelin - how to meet the whole family's sweet needs using just one eggwhite


It's a known fact that it's possible to increase the volume of an eggwhite by beating it for...well, lots of times. According to Hervé This (a French scientist, the founder of molecular gastronomy) it can be increased even more by just adding liquid and some sugar to stabilise the foam and increase the viscosity of water.

I was inspired by a post from blog.khymos.org to make the following experiment.

1 eggwhite
1.5 dl liquid (I used dewberry juice)
2-3 tsp sugar



I considered a suggestion from a comment and first dissolved the sugar in the juice. Then I beated the eggwhites for some minutes with an electric mixer (instead of 5-10 minutes as I didn't use my manual whisk, the wires of which are rather thick and would've made the job too time-consuming). It's important to use a really clean and dry bowl. While still whisking, I started to add juice. Bit by bit. And the volume really did increase, resulting in a decent bowlful of foam.

But that's not it yet. To prepare a fine dessert of this foam, you should heat it up a bit in a microwave to make the proteins set. Some tablespoonfuls at a time is a good way to do it. Hervé This has named this dish Vaquelin after the French chemist Louis Nicholas Vaquelin. As the proteins set really quickly, it's important to heat the foam only during a very short time or it will collapse. That's why I tried it using the 500W setting for different times: 5, 7, 10 and 15 seconds.



It's visible that the structure of the foam doesn't change much after 5 seconds. Although, after 10 seconds it already begins to collapse from the bottom when a spoon is stabbed in. 15 seconds makes the foam collapse entirely.
It seemed to me that the volume kept increasing in the microwave for about 8 seconds, after that it lessened a bit. That's why I used 500w and 8 seconds of cooking time for the final results.

After adding some berries and cinnamon the dessert was ready. With a funny and light texture that melts in the mouth and surprisingly warm for the eaters when served immediately. Still, it's possible to serve it a bit later too, the vaquelin will gladly wait. The dessert is definitely innovative. A good perspective for university students with money problems? Or weight-watchers? It's also suggested to use orange or cranberry juice as the liquid or even red wine. Worth to try anyway!

8 comments:

Anonymous said...

Very nice pictures! I'm glad the experiment was a success!

Martin,
webmaster(at)khymos(dot)org

Anonymous said...

That top picture is impressive. I thought I had come close, but my technique is clearly not to snuff. I am determined to try again with the electric whisk.

Anonymous said...

I followed your recipe bit by bit but still failed. Why?

Evelin said...

I'd really love to tell you why but since you haven't specified what exactly happened to your experiment, I can't. So, any details to come?:)

Anonymous said...

Well, I might have overwhipped it or added the liquid at the wrong time. I'll try again and fill you in on it.

Anonymous said...

I also had trouble with this experiment. Here is what I did and what happened:

Whipped the egg white with an electric whisk until almost stiff peaks. then started slowly adding my liquid at a rate of about 1 tbsp per 10 seconds. (100mL of 100% orange juice with 2 tsp sugar dissolved in it) I couldn't even use all of my 100mL before my foam started seriously collapsing and there was some separation of liquid from the foam. I tried once again adding the liquid even more slowly and the same thing occured. What happened??

Evelin said...

I tried it again today. Succeeded!:) I let the eggwhite foam reach soft peak stage and then started adding the liquid, 2 tsp - 1 tbsp at a time.

And blackcurrant juice gave it a cute colour! Though right now I'm thinking about trying new flavour combinations. There's still so much about this idea to try;)

Hope it works for you!

Anonymous said...

How stable should the foam be ?