How to make a foam sauce

[Cookwithlove]

Hi chefs,

How to make a foam sauce from lobster bisque or a basic foam sauce? Appreciate for sharing and thanks alots.

[TheTInCook]

Gel a rich lobster stock, maybe add some cream, and shoot it through an iSi?

[pastrygirl]

Gel a rich lobster stock, maybe add some cream, and shoot it through an iSi?

With the isi, you need thickener of some sort - enough fat to approximate whipping cream, or a fair amount of gelatin. These will make foams on the mousse-ier end of the spectrum, more towards shaving cream. (I've only used the isi with cold foams, they do make a version of the charger that is safe to be held warm).

For looser, soap-bubble type foams, I believe those are made with lecithin and agitated with a mini milk frother (http://www.google.com/products/catalog?q=milk+frother&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&tbm=shop&cid=15285042771434471703&sa=X&ei=otsLTonSMKnmiALq2cm2Cg&ved=0CKMBEPMCMAM) or perhaps an immersion blender.

[TheTInCook]

Are gelatin foams and fat antagonistic?

[Cookwithlove]

Thanks for the contributions. good day and cheers!

[pastrygirl]

Are gelatin foams and fat antagonistic?

At the extreme they would be, but that's OK because you don't need both fat and gelatin to stabilize. Gelatin binds with the water in a liquid and not the fat. You can set whipping cream with gelatin to make panna cotta, but you probably don't want to go much higher fat than that. As a pastry chef I almost always have something in my isi canisters, right now I have a thick milk chocolate malted creme anglaise that comes out as a very light mousse. I've done sabayon that has only a modest amount of heavy cream, so the egg yolks are probably equally responsible for foam-ability in that one. Also vegan chocolate mousse, essentially chocolate and water stabilized by the cocoa butter content. I once did a rose gelatin mousse that was a little tricky to keep at the right temperature, no fat in that just gelatin. Too cold and it didn't want to come out (solidified), too warm and the gelatin melted and the foam was too soft/unstable. I have not tried agar for isi foams, but that may have potential. You can make agar fluid gels by setting a liquid with agar then pureeing it, the result is a nice nape' consistency (or as thick as you like) that does not re-solidify (unless you re-melt it), might be able to stand up to the charger.

[KennethT]

It depends on whether you want the foam to be warm or cold, but if you want a warm foam, I think agar is your best bet, as pastrygirl said. Make an agar fluid gel with (if I remember correctly) 1% agar, then bring up to temp (just don't go over 85C or the agar will melt) and add to ISI whipper - I think I used to charge twice, with the first time done with the handle depressed to get all the air out of the canister. You can keep it warm for a few hours with no problems.