Sous-Vide

Sous-vide, French for "under vacuum", is a method of cooking food sealed in airtight plastic bags in a water bath for a long time—72 hours is not unusual—at an accurately determined temperature much lower than normally used for cooking, typically around 140 °F. The intention is to maintain the integrity of ingredients.

The method, first described by Sir Benjamin Thompson (Count Rumford) in 1799, was re-discovered by American and French engineers in the mid-1960s as an industrial food preservation method. The method was adopted by Georges Pralus in 1974 for the Restaurant Troisgros (of Pierre and Michel Troigros) in Roanne, France. He discovered that when foie gras was cooked in this manner it kept its original appearance, did not lose excess amounts of fat and had better texture. Another pioneer in the science of sous-vide is Bruno Goussault, who further researched the effects of temperature on various foods and became well-known for training top chefs in the method. As Chief Scientist of Cuisine Solutions, Goussault thoroughly developed the parameters of cooking times and temperatures for different foods.

Until the advent in the twentieth century of accurate ways of measuring and controlling temperature, and knowledge of pathogens and pasteurisation, sous vide could not be a practical or safe technique.

The primary feature of sous-vide is the use of temperatures much lower than for conventional cooking. The exclusion of air is secondary: it allows cooked food to be stored, still sealed and refrigerated, for considerable times, useful for the catering industry but less so for domestic use; and it excludes oxygen from food that requires long cooking and is susceptible to oxidation, e.g., fat on meat which may become rancid with prolonged exposure to air.

Times vary considerably. A thin cut of fish may cook in a few minutes. Some otherwise tough cuts of meat, for example beef brisket and short ribs, benefit greatly from very long (48 to 72 hours) sous vide cooking at medium-rare temperatures of around 131 °F (55 °C), but the enzymes in chicken, and particularly fish, turn the food into mush after much shorter times.