Most people have only a vague idea about sous vide, as some kind of curiosity from the field of haute cuisine. And many have never heard of him. While sous-vide is available to everyone, dishes prepared using this technology retain a maximum of taste and nutrients. How sous vide works and what to look for when choosing a device – in this article.
How sous vide works
Sous-vide (from the French “sous-vide” – “under pressure”) is a technology for cooking products in vacuum packaging at a relatively low temperature (55–85 ºС). The technology was developed about 50 years ago by a French chef. Not surprisingly, at first, sous-vide dishes were available only to visitors to elite restaurants and cost a lot of money.
Fortunately, the technology is quite simple, you don’t even need any special devices to use it – you can try to cook a sous-vide dish in a slow cooker , or even in a simple multicooker if it has a heating mode or long-term maintenance of a small (55–75 ºС ) temperature.
The main difference between the technology is that the products are placed in a vacuum bag before cooking. It is best to do this with a vacuum cleaner , but, in extreme cases, you can simply wrap the food tightly with cling film.
The combination of packaging and low temperature allows you to save the structure of the product, all its juices, a maximum of useful and nutritious substances. In addition, a dish packed with a vacuum cleaner is easy to store and transport, it does not spoil for a long time even without a refrigerator. There are many recipes for sous vide on the Internet, try to cook a steak or chicken breast according to these recipes and the result will surely surprise you.
Why do we need sous-vide as a separate device? Then, for proper sous-vide cooking, it is important to accurately maintain the temperature of the water on all sides of the package. A slow cooker cannot provide this, even if it has a keep warm mode. The temperature of the water in the multicooker at different points in the bowl can be different, especially if the bag with the product is large and divides the bowl into several sections. In some of them, the water can warm up to a boil, in some it can remain cold. Sous vide also provides uniform heating of the entire volume of water.
In addition, maintaining the temperature to the nearest degree is rarely provided by other devices. And in recipes for sous-vide, “heat water to 62 ° C” or “cook 10 hours at a temperature of 56 ° C” is often found – and these recommendations should be followed. So if the advantages of sous-vide technology did not leave you indifferent, it is better to buy a special device.
Submersible or stationary
Sous-vides are divided into two types and their representatives are so different from each other that it is just right to take them for completely different devices. Submersible sous-vides, by the principle of operation, are closest to boilers – they are attached to the edge of the dish and heat the water with a heating element lowered into it.
True, there are still differences – submersible sous-vides are equipped with temperature sensors and processor-controlled heating of the heating element, which ensures accurate maintenance of the heating temperature. And so that the water warms up evenly throughout the vessel, submersible sous-vides mix it with a built-in circulation pump.
Such a device is very compact and definitely does not take up extra space even in the smallest kitchen. In addition, it has no restrictions on the volume of dishes – submersible sous-vide can be used with any container.
The main disadvantage of submersible sous-vides is that it is impossible to close the dishes tightly. Because of this, the water in the dishes evaporates and cools, and the consumption of electricity increases. There are two ways to solve the problem:
cook a dish in a plastic food container, making a slot in its lid for the appliance;
purchase special balls floating on the surface of the water and creating a thermal insulating layer.
Stationary sous vide contains a built-in water tank heated by heating elements. Many stationary sous vides are also equipped with a circulation pump.
Such devices provide more accurate temperature maintenance in the entire volume of water due to heating by heating elements from all sides and a tight-fitting lid.
However, stationary sous vide are cumbersome and limited in scope. In this case, the minimum allowable filling volume is 60% of the maximum. That is, in a stationary sous-vide with a capacity of 12 liters, you will always have to fill in at least 7 liters of water – even if you are cooking a couple of shrimp.
Characteristics of sous vide
Power affects the rate of heating water. An 800 W sous vide will heat 10 liters of water in about 30 minutes, and a 1500 W sous vide in 15. In addition, low-power submersible sous vides may not be able to cope with heating a large volume of water – it will cool faster than its sous vide warms. However, in the latter case, it is enough to simply insulate the container by wrapping it in a dense fabric.
For home use, 800-1000 watts is enough. If you plan to cook dishes in large volumes, choose a device with a power higher than 1000 watts.
The circulation of water contributes to a uniform distribution of temperature throughout the volume. Since the uniformity of heating is one of the main conditions for cooking sous-vide dishes, the presence of such an option in the device is highly desirable.
Some stationary sous vide do not have circulation, providing mixing of water due to convection, but this only works if the volume of liquid significantly exceeds the volume of the bag with the dish. If the bag occupies a large part of the bowl, in the absence of circulation, cold zones may form.
accuracy The minimum accuracy of sous-vides is 0.5 ºС, while in recipes the temperature is set with an accuracy of one degree. It would seem that this parameter can be ignored, but this is not entirely true.
An accuracy of 0.5 ºС means that when a certain temperature is set, its real value can be either more or less than the set one by half a degree, which in total gives one degree of error.
For home use, this is not critical, but professionals prefer to use devices with an accuracy of 0.1 ºС.
Most sous-vide dishes are cooked below 85°C. The maximum temperature of the devices is higher – it varies from 90 to 99 ºС. So the quality of cooking does not depend on this parameter. Another thing is that the appliance with a high maximum temperature can be used for cooking other dishes: stews and vegetables, soups, etc. recipes for slow cookers .
The volume of stationary sous-vides is quite large and is 8 liters for the smallest models. But this volume is not at all equal to the volume of the finished dish. When cooking, water must circulate freely around the product bag. It is desirable that the total volume of bags lowered into the water does not exceed 50% of the sous-vide volume.
So an 8-liter appliance has a usable volume of 4 liters, which is quite comparable to a small multicooker.
For a small family, 8 liters will be enough. If the family is large or professional use of the sous-vide is expected, it is better to choose a larger volume – 10-12 liters.
The minimum temperature for sous-vide cooking is 55 ºС, all appliances are able to maintain it. Another thing is that sous-vide with a minimum temperature below 55 ºС can be used for making yoghurts, proofing dough, etc. This increases the versatility of the device.
Sous vide options
For home use, a submersible sous-vide with a power of 500–1000 W will be convenient – it does not take up much space and can be used with dishes of any size.
For frequent cooking of dishes of a certain volume, a stationary sous-vide is well suited – due to the thermal insulation of the bowl, it heats up water faster and consumes less electricity.
To ensure uniform heating of the water, choose among models with circulation.