Sous Vide means 'in vacuum' in French. As the name suggests, it involves cooking foods at lower temperatures for longer time so as to retain the moist juices and yet cook the meat to perfection. Sous vide style of cooking allows you great levels of control over the temperature.
Typically, for the sous vide cooking technique, you need a temperature-controlled water bath and vacuum-sealed plastic bags. This cooking technique works very well with different types of meat and seafood. What started in the mid-1970s at a Michelin Three-Star restaurant to cook delicate foie gras to perfection, the sous vide cooking technique has now even gained some degree of popularity with home cooks.
Cooking of meat releases the characteristic flavor - whether you grill or fry or bake. Every method of cooking results in a browning reaction called as Maillard reaction. When the proteins in the meat combine in certain way with the simple sugars, the outer layer turns brown which vary based on the temperature, moisture present in the meat, technique of cooking and the time. We can always tell what is cooking by the aroma released by the meat or sea food. The Maillard reaction, or its absence, helps us to distinguish the flavor of boiled/steamed meat from grilled or fried meat. Direct dry heat can quickly induce the Maillard reaction which on the other hand will be impeded when the meat is immersed in water. That is why it is better to sear the steak before vacuum sealing them for cooking sous vide. But this technique may not be advisable for lambs for which it would be preferable to sear after cooking sous vide.
Named after the French physician and Chemist - Louis Camille Maillard, the brown reaction typically occurs in a narrow temperature range of 280 - 350 degree F. If the temperature is very high it results in pyrolysis - burning of the food. Pyrolysis often produces chemical changes in the surface of the meat which may turn carcinogenic. Now you know why Cooking is called as Science as well as an Art.
It is not just the proteins in the meat that imparts the unique flavor and aroma. The fat in the beef imparts the marbled appearance that gives the best flavor when cooked. In Fish, the fat is not compartmentalized like in beef but distributed across the whole of fish. This fat coupled with the light structure of protein in fish gives the unique strong flavor you would expect from fish.
Getting started on Sous Vide cooking technique
Get yourself a good temperature controlled water bath. Alternatively you can use an immersion circulator to heat and circulate water in a pot at desired temperature.
The plastic bag keeps your meat with its juices trapped within and allows for efficient transfer of heat from the water to the food within. While you can go in for good quality zip-lock bags, it would be ideal for bags to be vacuum sealed after the meat is placed inside.
In fact keeping food away from air has always been the traditional method to arrest its decay. Sealing the meat within the bag also keeps it from drying out. Instead you get tender meat pieces that are moist with their own juices. The humid environment within the bag ensures that the meat is well braised and juicy. Maintaining the temperature allows the meat to be evenly cooked. You can do away with the rare centers and dry edges! You can get evenly-cooked meat and fish. As for the nutritive value, the carotenoids and flavonoids are retained and the delicate fats remain un-oxidized.
Using plastic bags at high temperatures is a cause for concern. Be sure to use food grade plastic bags that are certified for cooking and safe to use. Eschew cheaper plastic bags and pouches that can leach BPA and toxic metals into the food.
When you cook meat in sous vide technique, the Maillard Reaction does not happen â€“ so you do not get the attractive browning on the outside of the meat. This can be fixed by a blast of high heat once its ready to be served.
Sous vide cooking tips
Most often sous vide cooking is done at low temperature for longer time. This may need some changes in the way the meats are marinated and the amount and type of seasonings used. Roasted or powdered garlic works better than raw garlic pods. You can use marinades on the meat during the sous vide cooking process. But you must be sure that the marinade is not very acidic or alcoholic.
Such marinades will not reduce during cooking as it is in a vacuum. Since the role of acidic marinades is to tenderize meat, they are not required in sous vide cooking. But flavorful marinades can be frozen and then rubbed on the meat before it is placed inside the vacuum bag. Herbs, spices, lemon wedges etc can be used in the plastic bags to infuse flavor. Dried herbs are better for sous vide cooking. Whole spices might be too overpowering. Do not salt the meat before the sous vide process as it might lead to a pickled flavor and texture.