Sous vide is a French word which means “under vacuum” . This method was developed in mid 1960’s as an industrial method for preserving food. Sous vide cooking is a way of cooking in which the food to be cooked is first sealed in an airtight plastic bag. After this, the plastic bag containing the food is placed in a water bath and is steamed in a temperature controlled container for more than 95 hours of normal cooking times at temperatures lower than the normal cooking temperatures. The temperature under which the food is cooked is between 55 to 60 degree Celsius or 131 to 140 degree Fahrenheit. The temperature specifications are made as per the food being cooked so that it can be cooked evenly from inside and outside, avoiding overcooking and preventing the moisture in the food from being lost.
The food is packed inside plastic bags before cooking to keep the juices and aroma preserved. The food is kept in water bath with a fixed temperature i.e. the final cooking temperature set for cooking so that it is not over cooked. The temperature used for cooking is lower than temperature used for conventional cooking so that the cell walls of the food being cooked are preserved and the succulence in the food is preserved. The spices that are enclosed with the food inside the packet spreads the flavour more intensely. The removal of air(oxygen) also has a great importance as it prevents oxidation and allows the cooked food to be stored healthily and preserves it from being spoiled.
There is one limitation to Sous vide cooking. It is that the browning of the food(if required) can only be done at much higher temperatures only i.e. the temperatures above the boiling point of water.
The food cooked using Sous vide technique should be safely used. The food is advantageous to those suffering from low immunity where as it is not suitable to be consumed by a pregnant woman. The food should be cooked carefully as due to the absence of oxygen a bacteria named Clostridium botulinum can grow in the food and generate botulinum toxin in it. This toxin can be harmful if consumed. The food cooked Sous vide should be served within four hours of cooking.
This method is being used by chefs in many gourmet restaurants. Amtrak, the American passenger railroad service uses this technique to serve the food to its travellers. The method is being used today to produce food for people suffering from natural disasters.
Sous vide wizard is an online resource center that is working on teaching the ordinary people about how to cook healthy and tasty food easily using Sous vide technique. This website helps the people to learn about the history of this technique along with how to select a Sous vide cooker carefully and many recipes starting from the basics.
The following pictures shows Sous vide cookers with attached thermometers to set the temperature for the food along with how food is cooked using this technique.