Sous-Vide: Lower, sometimes slower cooking

In the past we’ve talked about cooking low and slow; it’s the technique used by barbecue pitmasters to prepare traditional BBQ cuts. Meat is left at low temperatures (250-300°F) for long periods of time (up to 24 hours). Well, here’s another technique for preparing your favorite cuisine that involves going even lower, and much slower, than anything you’re used to. Welcome to Sous-vide 101!

Sous-vide (French for “under vacuum”) and pronounced “soo-veed” is the method of cooking food that has been vacuum sealed in air-tight plastic bags in a water bath for long (72 hours is not uncommon) periods of time. The baths are kept at accurately determined temperatures – much lower than normally used for cooking (typically 120-140°F).

However, just like cuts cooked in the traditional manner, cook times will vary based on portion size. And because water is a much better conductor of heat than air, a thin filet of salmon set to 120°F will be ready to eat in no time (10-20 minutes).

The sous-vide method was first described in the late 18th century by Sir Benjamin Thompson and has since been rediscovered by French and American food engineers in the late 1960’s. The intention of sous-vide is to cook food items to the same doneness throughout, and to maintain the savory and juicy characteristics that might otherwise be lost with other techniques.

The use of temperatures much lower than conventional cooking (or even BBQ) is an essential feature of sous-vide; it results is a much higher succulence. Hold on, here’s the science:

At lower temperatures, cell walls in the food do not burst. In the case of cooking meat, tough collagen in the connective tissue can be hydrolyzed into gelatin without heating the meat’s proteins high enough that they denature to a degree that the texture toughens and moisture is wrung out of the meat. Also, by placing food in a water bath whose temperature is set at the desired final cooking temperature, overcooking can be avoided, because the food – and this is a scientific fact – cannot get hotter than the bath it’s in.

Conventional high-heat cooking, such as oven roasting or grilling, food is exposed to heat levels that are much higher than the desired internal cooking temperature. In the case of grilling, temperatures can reach as high as 800°F. Using a fast an accurate thermometer, food must be removed from the high heat prior to its reaching the desired internal temperature.

With precise temperature control (a water bath set to the same temperature as your target cooking temperature), very accurate control of cooking can be achieved. Additionally, uniform temperature can be achieved throughout your dinner, even with irregularly shaped or very thick items – given enough time.

One drawback is that the natural browning that occurs at much higher temperatures isn’t possible with sous-vide cooking. In some cases, meats and other foods cooked with the sous-vide technique can be browned using a grilling or searing technique either before or after being place in the water bath. This browning is done at high heat and only for a short time to avoid over cooking the interior of the meat.

Celebrity chefs and gourmet restauranteurs take full advantage of the sous-vide method because of its ability to preserve food textures and flavors; and it has become a common feature on television cooking shows. The good news is that this complicated cooking technique doesn’t have to be reserved for high-end restaurants and top chefs. With a little bit of know-how, you can utilize the sous-vide method in your own home.

Keep an eye out for part two of Sous-Vide: Lower and slower cooking when we’ll talk about best practices for building your very own sous-vide water bath.