Cooking sous vide - not your Mom's "boil 'n bag"

Cooking in a vacuum preserves flavor and prevents overcooking, if done professionally.  I wonder if home vacuum bag systems and an immersion heater could accomplish the same thing?

Shades of Green

Cooking green vegetables: why sous vide is better

By Aki Kamozawa and H. Alexander TalbotPosted 01.27.2009

"sealed in a bag using a vacuum pressure chamber, dropped into boiling water and cooked for four minutes"..."the stalks cooked sous vide had a much more intense celery flavor, especially when compared to the other ones. "

"Two of the main challenges when cooking green vegetables are retaining the verdant hues and emphasizing the fresh flavors on the palate. "

"change occurs because chlorophyll contains an atom of magnesium at its center. When the vegetables are heated for longer periods of time or exposed to acid, the magnesium is removed from the center of the molecule and replaced with an atom of hydrogen, which in turn changes the chlorophyll a and chlorophyll b into pheophytin a and pheophytin b. This transformation changes the pigment from a bright green to more of a grayish-green color."

http://www.popsci.com/diy/article/2009-01/shades-green

"Sous Vide - A Revolutionary New Cooking Technique

"Sous vide is the new culinary technique that has excited foodies worldwide. In the new cookbook Under Pressure: Cooking Sous Vide... explains why this innovative technique,which involves placing food in airless, submerged bags and cooking at precise, very low temperatures, yields such wonderful results.

"For the first time, one can achieve tender short ribs that virtually melt off the bone even when cooked medium rare. Fish and shellfish that stays succulent no matter how long it's cooked and fruit and vegetables that retain fresher color and flavor while transforming in texture. The secret to sous vide is to discover the exact amount of heat (and time) needed to achieve the best results. This is not your Mom's old boil-in-bags. After years of tireless trial and error, Keller and his assistants have achieved perfection in this collection of never-before-published recipes from his restaurants...

"...[the] book is definitely geared toward culinary professionals... It would be difficult for the home cook to use the sous vide method of cooking at home because the equipment neccessary to achieve proper results, temperature-maintaining immersion circulators and chamber vacuum packers, are expensive and if done incorrectly the food can be unsafe to eat. Perhaps in time, as the technique becomes more common place, the equipment and utensils needed will become more readily available.

http://hubpages.com/hub/UnderPressureCookingSousVide

It sounds like vacuum bags do certainly work to keep food fresh:

Two products promise fresh food - Consumer Reports Jun 08

The claims. Press a button on the Reynolds Handi-Vac Sealer for about 10 seconds and it sucks the air from an attached bag of food, "virtually eliminating freezer burn," those unsightly (but not unsafe) dry patches that can afflict frozen food. The device costs about $10, the quart- or gallon-size bags you use with it cost 24 cents or 37 cents each, and it takes six AA batteries.

Quick Seals are plastic zip-slider tops with adhesive strips. Attach them to food boxes or bags to "seal in freshness." Cost: 20 cents per seal, and they aren't reusable.

The checks. We put steaks in bags sealed by the Handi-Vac; in bags sealed by the Tilia Food Saver, a $100 vacuum sealer; and in Glad, Ziploc, and Hefty zipper freezer bags.

We left all bags in a freezer for more than a month, speeding freezer burn by turning the freezer off for 3 hours each day. We attached Quick Seals to original bags or boxes of crackers, chips, and other snacks, placed the same snacks in Glad and Ziploc bags, and used a clip to close several bags of chips.We left all bags and boxes for five weeks.

CR's take.Both sealers were the real deal. Steaks bagged by the Handi-Vac were free of freezer burn. The Tilia also worked. Steaks in Glad and Ziploc bags had lots of ice crystals; steaks in Hefty had some. Quick Seals kept snacks' flavor and texture as fresh as in a newly opened bag or box. Clips worked equally well (though just on bags) and are reusable. Glad and Ziploc bags didn't keep food as fresh-tasting.

http://www.consumerreports.org/cro/food/news/2008/06/two-products-promise-fresh-food/overview/vacuum-sealer-ov.htm?resultPageIndex=1&resultIndex=1&searchTerm=vacuum%20food%20seal