Friday, January 22, 2010

Espresso Caviar: Experimenting with Hydrocolloids

Hydrocolloids are defined as ingredients that interact with and control water. For example, xanthan gum, which you've probably most seen at the bottom of ingredient labels of packaged foods. Most come from natural sources like seaweed (carrageenan, agar agar, alginate), seeds (locust bean gum, guar gum), tree sap (gum arabic), and fruit (pectin). Some, like methylcellulose, don't occur naturally. Chefs over the past years have become entranced with taking these substances and using them to manipulate ingredients. Some of the most famous for doing this well are Ferran Adria of El Bulli, Grant Achatz of Alinea, and Wylie Dufresne of WD-50.

An article out of Food Arts gives a compelling argument: "Hydrocolloids allow chefs to take any pure flavor and, by adding a small amount [typically less than 1 percent] of a tasteless hydrocolloid, achieve any texture or consistency desired. Take a sauce. Thickening it by reduction alters its taste; thickening it with cornstarch or flour masks flavor, alters appearance, and requires heat. By adding a very small amount of xanthan gum instead the sauce gains the desired body with no effects on flavor or look and without any heat, a much more precise way to thicken it." It makes sense in a way. On the other hand, is playing around with white powders cooking? Isn't there an art to reducing a sauce the perfect amount?

I'd seen Tony Bourdain eating at El Bulli for his show, I'd read about Grant Achatz in Michael Ruhlman's writings. But I just pushed it to the back of my mind, after all - the only way I could judge such things was to eat it myself. It wasn't until I saw a video of Sam Mason (former pastry chef of WD-50) making beet caviar and applying it to a pastry dish that I actually realized I might, too, be able to do that. Combined with the fact that I've been, well, bored for lack of a better word with the things I usually make. Not that I don't enjoy eating creme brulee or fruit tarts or cookies or cakes, but I already know how to make them well - this gave me a chance to try something new and exciting; a whole new world of possibilities, even if it does feel wrong on some level.

I used a recipe for "tea raviolis" and changed it to espresso. It involves an algin espresso base, dropped by a squirt bottle into a calcium bath. Once it's in for 30 seconds it beads, you strain it, rinse it and voila - espresso "caviar." The texture was nice but there was a strange thickness to it towards the end - I'm not sure if this was from the size of beads I made or from leaving it in the calcium bath for too long.

Either way, I'm glad it came out as it did, and for now my creative boredom is satisfied.