Vacuum cooking: the Gastrovac

When you write a blog called Vacuum, you get all kinds of traffic to your site that you don't expect or plan to see any sense in. Then, slowly but surely, you feel an unexplainable compulsion to be an "internet expert" (i.e. someone who quotes really well from real experts) in all things vacuum.

Thus, this note on vacuum cooking, and the remarkable device called the Gastrovac.

A photo of this apparatus on Flickr (I'll thumbnail it here when I get permission).

Time Magazine: "Adoring a vacuum", Sept 2006

The patented Gastrovac is the result of that kind of collaboration. To design it, Torres and Javier Andrés, of Valencia's well-regarded La Sucursal restaurant, joined forces with a team of scientists at Valencia's Polytechnic University. But there's a big difference to the Gastrovac's goal: while Adrià and Blumenthal routinely rely on kitchen alchemy to turn one food into another (this summer's menu at Adrià's El Bulli in Rosas, Spain, features gelatin and olive oil made into "false olives" and melon turned into caviar), the Gastrovac uses technology to make food taste more like itself.

International Cooking Concepts: Gastrovac, the vacuum revolution

The Gastrovac is a compact appliance for cooking and impregnating in a vacuum. It is patented in over 160 countries and developed with the Universidad Politécnica de Valencia and the cooks Javier Andrés (La Sucursal Restaurant, Valencia) and Sergio Torres (El Rodat Restaurant, Jávea). It functions as follows: by creating an artificial low pressure, oxygen-free atmosphere, the Gastrovac considerably reduces cooking and frying temperatures, maintaining the texture, colour and nutrients of the food. Moreover, the Gastrovac creates the “sponge effect”: when the atmospheric pressure is restored, the food absorbs the liquid around it, allowing infinite combinations of foods and flavours.

Details in the owner's manual (pdf)

IN ORDER TO CAUSE THE “SPONGE EFFECT” DURING THE VAUUM BREAKING PROCESS, IT IS ADVISABLE TO PRESS THE VACUUM BREAKING BUTTON SEVERAL TIMES (AS MANY AS POSSIBLE) UNTIL THE MEASURE GAUGE INDICATES ABOUT -0,5 BAR. ONCE THIS LEVEL IS REACHED, WE CAN THEN DISCONNECT THE VACUUM HOSE FROM THE OUTLET ON THE LID, OR PRESS THE VACUUM BREAKING BUTTON UNTIL THE MEASURE GAUGE INDICATES 0. THIS PROCESS WILL HELP THE PRODUCT TO ABSORB THE LIQUID WHERE IT IS DIPED

Technorati Tags: vacuum, gastrovac, food, sponge-effect, la-sucursal, valencia, google-mobile-docs

Comments

[Jason Black]

Arghhhh...just bought the gastrovac - it is almost impossible to use the bloody thing, instructions are vague, there is just the same o same ol gumpf out there from icc, not a single sausage of real tangible info - ok, so I want to fry in tempura batter. Do I dip the item into the batter, put into the cage and then heat up the oil? the batter would drip off! Do I heat up the oil, put the item in the batter into the tray, then vacuum, then dip into the oil and cook??? What do they mean, "cook without coming into contact with the oil" is it deep frying without oil contact....HELP ME BEFORE I LAUNCH THIS FROM THE 29th FLOOR OF MY HONG KONG APARTMENT PLEASE :-)

[What is a Gastrovac?]

This is a informative site, thanks for the info!

[Edward Vielmetti]

a nice post demystifying some of these approaches from chadzilla:

http://chadzilla.typepad.com/chadzilla/2007/10/vacuum-cooking.html

Compression must be done with the aid of the plastic bag. The amount of compression or force is adjusted by setting the millibars on your machine. Simply place produce inside the bag (we are doing this with watermelon and eggplant) and put it in the cryovac. The bag puffs up, then shrinks down into forceful compression. The hard plant cell walls are then crushed together as all air is removed from the interior of the food. What you are left with afterwards is noticeably smaller and different in appearance and color. With the watermelon or similar fruit or vegetable, you get a texture that slices super cleanly and tastes brighter and sweeter due to compression. The color becomes much more vibrant. With a softer flesh like that of the eggplant, you get a more meaty texture that can then hold up to more rigorous cooking methods (see the eggplant post). Sure it is arguable that this is still ROP product, but it does not have to be intended for storage or cooking. The product can be removed from the bag immediately afterwards and the result is still achieved. Let the oxygen flow!