How can I make good coffee if it's not fresh? What's the use of expired coffee beans?

Make a bag of coffee beans with the same brewing parameters, and suddenly one day, the coffee will not swell. You can basically judge that the bean is not fresh.

This "stale" does not mean that the coffee is undrinkable, it just means that the coffee bean is past its best flavor period. According to food safety regulations, roasted coffee beans have a shelf life of one year, in other words, coffee beans (whole beans) can be drunk within a year from the roasting date as long as they are properly stored.

When we often say that the coffee is not fresh, it does not mean that the coffee is out of date, but that the "good taste" escapes at the same speed as the coffee bean exhaust speed. When the coffee bean gas is exhausted, it is judged that the powder layer does not expand during steaming, which also means that the taste of the coffee is not as good as it used to be. The exhaust period of coffee beans does not have an accurate and fixed time limit. Some coffee beans are drained in 30 days, and some coffee beans can be steamed and expanded in 60 days. Therefore, Qianjie is cautious and generally advises guests to finish their drinks within 30 days. Although the theoretical shelf life of roasted coffee beans is one year, according to Qianjie's practice, if you open coffee bags frequently, the flavor of coffee beans will run faster, and the coffee that has been kept for a long time has lost its original aroma, leaving behind baked, stale, nutty and bitter. The coffee brewed in this situation is very bad. Therefore, if it is improperly preserved to make coffee beans stale and oily, it is better to abandon them and not to drink them. (here is another little knowledge: the storage performance of sealed cans is not as good as that of coffee bags with exhaust valve seals.) if the coffee does not expand during steaming and is within 60 days of the baking date, it can be saved by brewing. Steamed coffee powder does not expand, usually after steaming and injecting water, it will give off the smell of "almonds" and "peanut clothes". If you follow the normal brewing method, the final coffee flavor will highlight the bitter almonds and tea feeling.

If you are also in this situation, you might as well refer to the practice of Qianjie. Almost exhausted coffee beans mean that the lost flavor is irrevocable, so change the brewing parameters in order to show the remaining good taste of coffee beans as much as possible, but also to avoid bad taste. Coffee beans do not expand, there are two problems need to be solved, the first problem is that there is no gas emission of coffee, which means that water absorption is very fast. The second problem is that in the subsequent cooking process, the powder layer is not active and is deposited at the bottom, so it is very easy to block the water.

The purpose of steaming itself is to exhaust the gas, and for coffee, which is almost exhaust, if it is steamed for 30 seconds, it will taste bitter because of excessive steaming. But you can't get rid of the steaming process, because you still have to give some time to make the coffee powder completely wet. Therefore, the steaming time will be controlled at 15-18 seconds. The problem of easy blockage can be solved by coarse grinding and fine-tuning water injection. Coffee powder: 15g powder / water ratio: 1:15 grind degree: 20 sieve pass rate 75% water temperature: 92 degrees Celsius filter cup: V60 or flat bottom filter cup start the first stage of water injection steaming, steam 25 grams of water for 18 seconds, the water flow is as small and gentle as possible, because of non-expansion, the gap between particles is also large, easy to fall directly into the next pot. The second stage of water injection from the center around a small circle to push up the powder layer, so that the fine powder attached to the filter cup wall to prevent the fine powder from sinking to the bottom and blocking the outlet. It can be seen that a small foam has been washed out, this section of water injection to 150 grams.

When the water level drops to 1 stroke 2, inject the last section, use the middle current to circle quickly to create a whirlpool to "activate" the powder layer and force out the flavor substances. Stop injecting water until 225 grams, wait for the coffee liquid of the filter cup to flow into the next pot, remove the filter cup, and end the extraction. The total extraction time is about 1 minute 35 seconds to 1 minute 50 seconds. Although this method of brewing will not return the coffee to the rich and full flavor during the taste period, it will greatly avoid some defective flavor. If you still have a lot of coffee beans in time to drink, you might as well try this method.