Sous-vide cooking, once the domain of exclusive chefs, is now possible for home cooks. The food is vacuum sealed and simmered in a temperature-controlled water bath, cooking slowly to exact temperatures. Sous-vide cooking produces perfectly cooked food every time. Meats are tender and cooked to the desired degree of doneness. Vegetables retain their vitamins and minerals; nothing is lost to the cooking water. Food is never overcooked since the temperature is controlled.
Sous-Vide Cookng Method
The term sous-vide means "cooked under vacuum." Food simmers slowly in a vacuum-sealed bag, never coming in contact with the water. Using a water bath with a thermostat, food can be put in the water bath and ignored until it is time to eat. Foods can be safely held at your desired temperature in the water bath for 24 to 48 hours. Home cooks can now buy water baths designed for sous-vide cooking, and instructions are available online for using a slow cooker and a current regulator or rheostat to make your own.
Advantages of Sous-Vide Cooking
Since the food is vacuum-sealed, seasonings are drawn into the food. The food cooks in its own juices, enhancing the natural flavors. The food can stay in the bath for a reasonable time without drying out or over cooking, unlike with other heat methods. To cook a medium-rare steak, the water temperature would be set to 135 degrees Fahrenheit, the desired internal temperature for a medium-rare steak. The steak, vacuum sealed in plastic, slowly heats up in the water until it reaches 135 F, the water temperature. It cannot overcook and will remain perfectly cooked at 135 F until it is removed from the water. Additionally, all of the steak juices remain in the bag; no flavor or moisture is lost during cooking
Limitations of Sous-Vide Cooking
One of the biggest limitations of sous-vide cooking is that it cannot brown the food, which is one way many chefs add flavor. If you like a nice char on your steak, you must brown it under a broiler, fry it or grill it quickly before serving. Another consideration is the time required to cook by the sous-vide method. A large roast or brisket can require 24 to 48 hours to cook. This shouldn't be a problem as long as you plan ahead. The cooking process requires no extra work or close attention once the food is in the water bath.
Food Safety Concerns
Cooking in plastic causes some concerns. The plastic bags have been extensively tested and are approved for food use. Another concern is whether the food is adequately cooked to kill bacteria. If the food cooks too slowly, the bacteria may have time to reproduce and spoil the food before the food is cooked. Boil larger pieces of meat briefly first to kill surface bacteria, then move them to the sous-vide bath. Smaller pieces of food -- arranged in a single layer, not a solid block -- that cook within four hours should be safe with no additional preparation. Sous-vide cooking is safe as long as the cooking temperatures and times recommended in the recipe are followed and temperatures are controlled so that the water bath temperature does not cool significantly when food is added. The heat source must be capable of keeping the temperature at the desired setting throughout the cooking process.