What is sous vide cooking?
The main advantage of sous vide cooking is much less reduction of the output product, which is only 10% – in traditional cooking the reduction is around 20%. Thanks to the protective vacuum bags, food is well protected from the air and other negative factors, they prevent aerobic bacteria development and thereby lengthen the food’s life. When it comes to the taste, it’s unique, delicate and the structure is kept undamaged. What’s more, this technique favors preserving the vitamins and microelements and it doesn’t require as much spices and herbs as with traditional cooking. This is due to the fact that the natural juices are retained in the food.
The meal is closed in hermetic vacuum containers and becomes pasteurized in HTST (High temperature, short time) system. A heat-resistant material like PET (terephthalate) is used for packaging. Unlike traditional cooking in boiling water, sous vide is cooking in hot water much below the temperature of 100 º Celsius. The exact temperature depends on the type of meat or vegetables.
The table shows most recommended sample temperatures for sous vide cooking for particular products:
|Lamb||65 – 68 ºC|
|Beef||58 – 60 º C|
|Pork||65 – 66 º C|
|Chicken||65 – 71 º C|
|Vegetables||80 – 85 º C|
|Fish||58 – 60 º C|
• 58 -62°C – in 56 degrees the albumins are still raw and in 58°C they become white (the final color is a result of that we see the red color of meat through white, albumin fog covering muscle fibers). This temperature is recommended for fish and meat that are going to be served as bloody.
• 66-68 °C: Ability of the muscle tissue to absorb water is significantly reduced with heating over 68 degrees. This temperature interval is recommended for chicken and well done meat.
• 83-85 °C – this temperature is the best for vegetables because they need the temperature over 80 degrees in order to be properly cooked, but under 85°C pectin begin to hydrolyze and this is the reason why the temperature should be kept under that. It’s also good for meat rapid pasteurization.
Some people stated that cooking in bags in such low temperatures is the best way to develop botulinum. Goussault disproved this myth proving that long cooking time with correct cooling kills bacteria and microorganisms in the same way the higher temperatures do. It also lengthens expiry date much better than traditional cooking. Goussault also believes that high temperatures lead to irreversible food damage. The cell walls disintegrate and it makes it impossible to absorb the liquid which is lost.
There is also characteristic smell that accompanies the traditional cooking and it is not pleasant for every person followed by high heat level and condensing water vapor. It doesn’t occur in sous vide cooking, packaged meals are cooked in much lower temperature and the aroma along with the juices are kept in plastic bag. Vacuum sealing favors better osmosis between components placed in the bag. Thanks to this, the techniques of smoking and marinating have been improved and chefs don’t need to use as much spices. Chamber vacuum sealer is one of the best tools for sous vide cooking.
Sous vide has been approved not only by professionals, which are most prestigious restaurants chefs, but also amateurs that are not very familiar with every day cooking. Some chefs even think that sous vide is going to change the character of every cooked dishes.
Where did the sous vide cooking come from?
This method of cooking became popular in 70s in France, where the chefs from a Roanne-Georgesa Pralus village discovered great influence of cooking vacuum packed goose livers on their taste and appearance. Sous vide in French means “without an air” and it consists of bringing the interior of products sealed in plastic bags to particular temperature by putting it in the hot water.
Sous vide has great influence especially on preparing meats. Why? In cooking meat the most important process is denaturation of proteins, which is shear of the meat’s fibers. To make it digested easier, and not to lose its taste, the fibers must be damaged in particular way (even through heating). The main purpose is to keep subtle balance between truncated proteins and soft, juicy muscle tissue.
In sous vide cooking thanks to the fact that the bag with the product is not boiled, you achieve enough temperature to get rid of the hard connective tissue and it keeps the meal in its best quality. During the traditional cooking food loses water and its facture is changed, which is different than sous vide – in this case vacuum packed products do not lose the best part of the food – taste, vitamins and color.
How does it look in practice – on our plates?
Products cooked using the sous vide technique have much more delicate taste and their natural structure is not damaged during the cooking. Much more vitamins and micro elements are kept since all the natural juices are kept in the dishes.
Although, it’s worth noticing that preparing food using sous vide requires quite large amount of time – some kinds of meats need even over a dozen hours and fish – couple of hours. A lot of depends on the product’s quality and in the meat case – on its type and the effect we want to achieve.