Does nitrogen coffee use N2O or N2? The role of coffee filled with nitrogen.-how much nitrogen coffee is there?

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Nitrogen (N2) accounts for 78.08% of the total atmosphere and is the main component of air.

Nitrogen is an inert gas, which is not easily affected by temperature and does not increase color and taste. In food processing, it is filled with packaging to isolate oxygen and prevent food oxidation. Many coffee capsules are packaged with nitrogen.

If someone asks about the harm of nitrogen, you can answer him like this: "if the proportion of inhaled nitrogen is too high, it will die of hypoxia!"

● at low temperature and high pressure, nitrogen will dissolve into the coffee, once returned to normal pressure, will release a large number of small bubbles, foam floating in the coffee like a cold fog, and eventually form an Espresso-like dense foam.

(dynamic diagram of bubble formation)

Compared with uninflated coffee, nitrogen can increase the mellow feel of coffee and make the taste more dense.

The production of ● nitrogen coffee is divided into two steps.

"Coffee preparation" and "nitrogen blending"

The coffee-making process is very mature, and the addition of nitrogen is not complicated, but some special equipment is needed.

● so, let's talk a little bit about how to make a cup of nitrogen coffee--

Everyone likes different flavors.

The author is a self-brewing beer lover, once with a coffee roaster friend Renault to cooperate with a coffee beer.

For the first time, I used a slightly sour shallow baked Yega Chuefei, which, in my opinion, could not be called beer at all, but Renault liked it after tasting it.

For the second time, medium-depth Mantenin was used, and the proportion was reduced, mainly with the flavor of malt and hops, but Renault felt that it did not reflect the sour taste at all.

Therefore, as far as a drink is concerned, it is a matter of opinion which flavor is better.

● flavor

The effect of nitrogen retention is more reflected in the taste, but will not change the flavor too much. However, if the mixed gas is used for gasification, it needs to be adjusted according to the specific gas characteristics.

● production method

Cold extraction is the main way to make nitrogen coffee. Coffee powder is extracted at low temperature for a long time to dissolve the oil and aromatic substances with flavor, which avoids the bad flavor produced by high temperature reaction. Ice droplets and ice brew are good choices.

In addition, there are baristas who use Espresso to make nitrogen coffee, espresso is thicker, nitrogen will make it have a milkshake effect, the experience is completely different, and it takes more time to make.

● gas

Nitrogen coffee generally uses "pure nitrogen" or "nitrogen-carbon dioxide mixture".

Both food-grade gases are available at the almighty TB.

However, manufacturers generally do not sell the mixture directly, so they can only buy one more can of carbon dioxide and mix the proportion on their own.

● pure nitrogen

Nitrogen is usually insoluble in water, unless you use a low-temperature and high-pressure container to deal with them, and as soon as they are out of trouble, they will become moisture insoluble.

But don't worry, pure nitrogen will not erupt like cola, and even if it shakes violently, it will only slowly form a pile of cloud-like bubbles that rise slowly and eventually form a thick white foam.

Pure nitrogen (99.999%) is colorless and tasteless, does not change the flavor of any coffee except taste, and is safe and non-toxic.

● oxygen-carbon dioxide mixture

The gas mixture was first used in nitrogen beer, where carbon dioxide is an essential ingredient that quickly takes away heat from the body and makes people feel cool. On the other hand, nitrogen increases the mellow thickness of beer, making beers like Milk Shitao have a smooth feel close to milk.

People who have made carbonated sodas should know that carbon dioxide brings some sour taste. This sour taste is not necessarily a bad thing. If you want to experience it, you can buy a bottle of Coke, pour it out in half, and then shake the cola in the bottle until it is out of breath. Under the comparison of the two cups, you can feel the difference between Coke and sugar water.

The gas ratio is recommended to be maintained at 7% nitrogen, 3% carbon dioxide, the more nitrogen, the finer the foam, the more carbon dioxide, the more carbonated, and the thicker the foam. If you use pure carbon dioxide, it will become carbonated coffee. Interested friends might as well try it.

In addition, carbon dioxide volatilization is more intense, it is best to use the "cup wall flow" method to avoid getting wet.

After ● knew the characteristics and differences of the raw materials,

Let's take a look at how nitrogen coffee is made.

First of all, we need a pressurized KEG bucket to prepare 2 liters of filtered water.

After the jar is sealed, it is cooled to 6 ℃ in the refrigerator, which is close to the freezing point and meets the requirements of low temperature extraction. The cooling time is a little longer, and it is best to prepare it one day in advance.

When the water temperature reaches, you can start making coffee filter bags. According to 12:1 ratio, two liters grind 166g coffee, and the particles can be a little thicker.

A non-woven filter bag is used here, which is sealed with a heat sealing machine. Tea filter bags can also be used, but as the tea filter paper is easily damaged, the pot of coffee grounds blocking the wine hole is useless, so it is necessary to cover two layers to make a double insurance.

-set of double-layer-

Put in the coffee bag, close the lid, start to recharge, recharge and release. The aim is to drain the oxygen, maintain the flavor of the coffee, and check the airtightness.

Put it back in the refrigerator and keep it for 48 hours.

After the extraction, take out the coffee bag.

After the third charge and release again, the gasification officially begins.

Gasification requires a certain pressure, which can only be observed with the help of a barometer.

There are three kinds of barometer units on the market: Mpa, Kpa and Bar.

1Mpa=1000Kpa=10Bar .

We need pressure stabilization in 0.2Mpa.

That is, 200Kpa or 2Bar

Continue to put into the refrigerator, under the action of low temperature and high pressure, the gas is constantly mixed into the coffee, need to replenish the air regularly, and keep the pressure at 0.2Mpa until the pressure no longer drops.

-sampling-

Coffee is stored in the freezer and the flavor period can be prolonged at low temperatures. Through the pipeline output to the Tap, if there is a pipe refrigerator, the effect will be more perfect.

Production

There is also a way to make it with ice, which is cooler, but can affect the concentration and foam of the coffee. If you cooperate with refrigerators and pipe refrigeration equipment, you can throw away the ice.

END