How many methods are there for the preservation of coffee beans | how long will the coffee beans remain unchanged?

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Preservation of coffee beans: focus on fresh coffee beans

Like most foods, the fresher you are, the more you can taste the most authentic delicacies. So are coffee beans. The more fresh they are, the better the flavor is. It is not easy to buy high-quality coffee beans, you must not want to drink coffee with a greatly reduced flavor because of poor storage. Coffee beans are very sensitive to the external environment, and the best taste period is not long. How to store coffee beans correctly is a very important issue for people who pursue high-quality coffee.

First of all, let's look at the characteristics of coffee beans. When freshly roasted coffee bean oil is roasted, the surface will be shiny (except for shallow roasted coffee beans and special beans that have been washed with water to remove caffeine), and some reactions continue to take place inside the beans and release carbon dioxide. Fresh coffee beans emit 5-12 liters of carbon dioxide per kilogram. This exhaust phenomenon is one of the keys to tell whether coffee is fresh or not.

Through this continuous changing process, coffee will begin to get better after 48 hours of roasting. It is recommended that the best taste period for coffee is 48 hours after roasting, preferably no more than two weeks.

The best device for preserving coffee: one-way breathable valve

At present, the device on the market that can achieve the best effect of keeping coffee beans fresh is the one-way breathable valve (one-way valve), which was invented by Fres-co Company in Pennsylvania in 1980.

Why? Here to review the simple high school physics, the light gas moves faster, so in the space where there is only one exit, the light gas tends to escape and the heavy gas tends to stay. This is what Graeme's Law (Graham's Law) tells us.

Imagine a bag packed with fresh coffee beans with some remaining space filled with air, which contains 21% oxygen and 78% nitrogen. Carbon dioxide is heavier than both gases, and when coffee beans produce carbon dioxide, they squeeze oxygen and nitrogen out. At this time, if there is an one-way breathable valve, the gas can only go out, not in, and there will be less and less oxygen in the bag over time, which is exactly what we want.

The less oxygen, the better the coffee.

Oxygen is the killer of coffee beans, which is one of the principles that must be considered when selecting and evaluating all kinds of coffee bean storage products. Some people choose to poke a small hole in the bag of coffee beans, which is better than completely sealed, but the amount and speed of oxygen escape is limited, and the hole is a two-way pipe, and the oxygen from the outside will run into the bag. Reducing the amount of air in the package is certainly an option, but only an one-way breather valve can reduce the oxygen content in the coffee bean bag.

In addition, it should be reminded that the packaging with an one-way breathable valve must be sealed to be effective, otherwise oxygen can still get into the bag. Before sealing, you can gently squeeze the air out as much as possible, reduce the gas space in the bag, and have less oxygen to touch the coffee beans.

What is the general principle of coffee bean preservation?

Buy good quality and fresh beans, seal them in dark containers with one-way breathable valves, and place them in a dry, cool, sun-free and steam-free place. The flavor of coffee beans gets better 48 hours after roasting, and the freshest beans are kept at room temperature for two weeks.

Why there are so many eyebrows in storing coffee beans sounds troublesome.

It's simple, because good quality coffee is worth your trouble. Coffee is a very daily drink, but there is also a wealth of knowledge to study, this is the interesting place of coffee, feel attentively, taste the most complete and pure flavor of coffee together.

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