As Vide shows, vacuum cooking sounds like a foreign technology, and we have every reason to prove it: in the 1970s, French chef George Ray Ras.

Pralus) introduced this technology into the kitchen. At first, being abroad was neither complicated nor mysterious. The simplest vacuum cooking method is to immerse the ingredients in a container with precise temperature control for water bath, and the temperature of water is the final target temperature of the ingredients to be cooked. Need an explanation? Well, it can also be called ultra-low temperature boiling. It is precisely because the temperature of the water bath cannot be higher than the final target temperature that the food cannot be overcooked. The essence of vacuum cooking is to lock the temperature variable in the formula of "time times temperature".

The temperature selected by water bath method can just trigger the chemical reaction of some compounds in food (i.e. protein denaturation and hydrolysis), while other compounds keep their original characteristics. This is one of the greatest kitchen revolutions, which has greatly changed the commercial cooking scene in the past few centuries, but it was not until recently that this technology appeared in the United States. If I can only recommend you a new cooking method in the whole book, it is undoubtedly vacuum cooking. The reason for this is that the meat cooked in this way has no gradient change, but the outside of the bathtub will be overcooked, which is amazing. The whole ingredient has a uniform temperature and maturity.

The name of this method is sous.

Vide (meaning in vacuum) stands for a step in the cooking process, that is, putting food in a vacuum plastic bag and sealing it. The purpose of using vacuum bags-that is, plastic bags, which should be sealed after all the air in them is exhausted-is to let the water in the bathtub transfer heat to the food, but at the same time, it does not let the water directly contact the food. In other words, this means that water will not react chemically with food, and the taste of food will become richer, because water cannot dissolve the compounds in food and take them away. The name vacuum cooking is very interesting; But I think it should be called "water bath cooking" because the actual heat source is usually the water in the basin. I think everyone has used a double steamer. However, just like something called "molecular food", once something becomes popular, it will stop. )

Vacuum cooking does not have to use sealed bags in water. Some foods don't need this bag when cooking. For example, the egg itself has been sealed (of course, we ignore the tiny pores on the eggshell here), and we can use this technology for some auxiliary treatment. Vegetables such as cabbage need to be preheated before cooking. In these cases, it is harmful to put food in a sealed bag.

Vacuum cooked steak has no "bull's-eye" shape-that is, it presents a uniform three-dimensional shape from the center to the edge; The edge of the second steak is cooked, but it is still raw in the middle.

You can also use other liquids instead of water: for example, oil or melted butter. In addition, because meat does not absorb oil or water, it can even be unsealed when using one of the liquid media. In this way, those components that are difficult to seal can be treated like this. For example, chef Thomas Keller (Thomas Keller)

Keller) created a recipe for cooking lobster tails, that is, taking a water bath with butter and water (so-called suspension sauce, which is to mix and stir melted butter and water as a water bath medium with a boiling point higher than pure butter).

Technically speaking, air with controllable temperature can also work, but its heat conversion efficiency is much lower than that of water bath method-about 1/23 of the latter. Under low temperature conditions, such as140 f/60 c "air bath", it takes a lot of time to cook chicken and other ingredients. At this time, the growth of bacteria has become a serious problem that we have to consider. Using liquids such as water can ensure that heat can penetrate into food through contact-of course, it means that the liquid contacts the plastic container and the container contacts the food-which is much faster. Water is cheap and easy to use, so vacuum cooking is basically for you. Of course, some chefs occasionally use other liquids.