By Prerna Bhatia
Liquid Nitrogen is fast becoming one of the trendiest ways of gourmet cooking, and here’s why
With a freezing temperature of -210 ͦC and a boiling temperature of almost -196 ͦC, you wouldn’t expect liquid nitrogen to be used outside the laboratory, or by amateurs. But it is increasingly being used in the food industry in the preparation of frozen desserts, and more and more restaurants are using it, not because of the speed with which it freezes food, but the way it freezes food.
So, chances are that, besides seeing Heston Blumenthal and the MasterChef contestants use it on TV, you will see the chef in your favourite restaurant use it in your dessert.
What is Liquid Nitrogen?
Says Molecular Gastronomy Network, “The air we breathe is composed of approximately 78% nitrogen in its gaseous state, against 21% oxygen and 1% various other gases. To produce liquid nitrogen, the air is first liquefied and the nitrogen is then separated by distillation. Since the boiling point of nitrogen is -195.8°C (-320.5°F), liquid nitrogen is extremely cold, it’s a liquid said to by ‘cryogenic.'”
What is its use in food?
Liquid nitrogen, being incredibly cold, is used to freeze foods, which it can do almost instantly. The speed of the chilling also improves the texture of the food, and makes it a dynamic ingredient. While food is frozen in a conventional freezer, it forms larger ice crystals, which affects the consistency of the food.
On the contrary, liquid nitrogen forms microscopic ice crystals, thus giving a smooth texture to the dish. As a result, it is being used in gourmet cooking and is soon expected to be used in home cooking, too.
Heston Blumenthal, known for his scientific approach to cooking, is one of the renowned chefs who have brought the concept of liquid nitrogen to mainstream cooking. His Michelin-starred restaurant, Dinner by Heston, serves instant liquid nitrogen ice cream in an ice cream trolley to its diners.
Apart from ice cream, liquid nitrogen is used to freeze ingredients like berries, marshmallows and honey, which makes it easy to grind them into a powder, and edible flowers, which are used for garnishing.
Liquid nitrogen is also used to freeze alcohol, which has a freezing point of -114 ͦ C, and thus cannot be frozen in conventional freezers. It is, thus, extensively used in frozen cocktails and slurpies.
How does it work?
Many people are concerned that liquid nitrogen changes the taste of the food; however, it may only be due to the change in temperature. It only changes the texture of the food but does not leave it flavoured or poisoned in any manner.
Liquid nitrogen evaporates after flash-freezing, so the food to be frozen has to be put into the nitrogen, and not the other way round, otherwise, it would freeze only the top layer of the food.
Liquid nitrogen may not be the safest thing to handle, but by taking certain precautions, you can use it very conveniently. There are safety canisters which make it easier to use liquid nitrogen, coupled with the temperature resistant gloves and safety eye-wear which is sometimes used. Also, a little liquid nitrogen does not harm your skin, because it turns into gaseous form and evaporates.
Food made with liquid nitrogen should be rested for the nitrogen to evaporate, and brought to a normal freezing temperature. It may be used at home, but only in the guidance of a trained chef.
That being said, you cannot deny the fact that liquid nitrogen is one of the coolest things, and will soon be a trend in Indian gourmet cooking.
Image Credits: Google Images