What is the reason for the excessive sourness of hand-brewed coffee? How to sweeten coffee? How much water should I use to make light coffee?

"Sour" can be said to be the mainstream taste of coffee today. Since the popularity of high-quality coffee, the roasting of coffee has begun to turn from deep to shallow, and the taste has changed from unchanging bitterness to colorful acid. This attracted many friends who couldn't drink the "coffee flavor"(bitter) to start to come into contact with coffee and taste the sour aroma of lightly roasted coffee. But many friends found that the coffee they brewed at home never had the acid content they drank in the store. It was obviously the same coffee bean, but the coffee brewed in the store was sweet and sour, but the coffee brewed by myself was sour and uncomfortable. The sour was very sharp, like taking a raw bite of a lemon, sour and astringent. Obviously, a situation like this usually means that the coffee has not been sufficiently extracted, which is what we often call insufficient extraction. Front Street often mentions that flavor substances in coffee have different dissolution rates due to different molecular size and polarity. If we divide the coffee extraction process into three stages: front, middle and back, then the substances dissolved in the first stage are mainly acid, followed by sweet and bitter respectively.

There are checks and balances between flavors. The reason why the coffee that comes out is sour is because the sweetness and bitterness are not dissolved. For example, the reason why lemon is unacceptably sour is because it contains very little sugar content and the ratio between acidity and sweetness is seriously unbalanced. If we want to make a cup of sweet and sour coffee, we must dissolve appropriate amounts of flavors other than acid in the coffee. Just like all kinds of lemon desserts, sugar is added to balance the acidity of lemons. It is not difficult to do this, as long as you use the three important parameters of grinding, time, and water temperature.

1. Adjust the thickness of the grinding degree determines the water-contacting surface area of the coffee. When the grinding degree is finer, the larger the water-contacting surface area of the coffee, and the higher the rate at which the flavor substances dissolve. Vice versa. If we want coffee to get a sufficient extraction, then naturally we need a fine enough grind! That's true, but how detailed should it be? Like other parameters, how fine the grind of coffee is mainly depends on whether it can be matched with other parameters such as water temperature, time, and extraction method. For example, the grinding degree used by Qianjie when making lightly roasted coffee is fine sugar grinding, and the sieving rate of No. 20 sieve is 75% to 80%. This is because this grinding degree can match the water temperature of 92°C and the extraction time is 2 minutes. Match the time to make a good cup of coffee. If you can fix other brewing variables, you can try step by step to find out the grind level that suits you, because there is no fixed standard for grind level, and not everyone has a 20-gauge screen in their home. Grind it fine when the coffee tastes sour and sharp, and grind it coarse when the coffee tastes bitter. This is the simplest and most practical way.

At first, we can try to make it as fine as possible, because the density of lightly roasted coffee is high, and its flavor substances will be more difficult to dissolve. As long as the coffee powder pit that is washed out is not muddy, there will be basically no major extraction problems.

2. Extend the extraction time. As mentioned in the previous street, since we end the extraction before the sweetness and bitterness have been dissolved in large quantities, the taste of coffee will be sharp and sour. Therefore, extending the extraction time can effectively help us sweeten the coffee, because the extraction time is the time when water and coffee powder come into contact. When the extraction time is extended, sweet, bitter and other substances can naturally be dissolved in sufficient quantities.

There are many ways to extend the extraction time, such as the fine grinding mentioned in Qianjie above is one of them. In addition, the extraction time can be extended by replacing the filter cup or changing the brewing method. Generally, the flow rate of filter cups without ribs/short ribs and small outlet holes will be slower, because the gas released from the coffee beans during the brewing process does not have many channels to escape, and they will form a resistance to hinder the penetration of hot water, so the flow rate of filter cups without ribs/short ribs will usually be slower. By replacing it with this filter cup, we can effectively extend the extraction time of coffee.

Changing the brewing method is very simple. We only need to split the hot water into multiple injection stages to extend the extraction time. Affected by water pressure and waiting time, injecting hot water in a small amount and multiple times will always take a longer extraction time than injecting hot water in a large amount at once. This is also the reason why the three-stage extraction time is longer than that of the one-knife flow. Generally speaking, it is most prudent to control the brewing time in the range of 2 minutes to 2 minutes and 30 seconds. Of course, Qianjie does not mean that if you are outside this range, you cannot make good coffee. It mainly depends on the combination of other parameters and time. However, relatively speaking, controlling the brewing time within this range will not easily rush over-extracted coffee, nor will it make the coffee prone to insufficient extraction, and the fault tolerance rate is relatively high.

3. Increase the brewing water temperature The water temperature determines the rate of substance dissolution. The higher the water temperature, the faster the rate of substance dissolution, and vice versa. Through conversation, Qianjie found that the main reason why many friends failed to make light roast coffee was that they did not use the right water temperature. For example, some friends use hot water from office water dispensers for boiling. Except for some high-end models, the temperature of hot water from water dispensers is generally in the range of 85°C to 88°C. For deep-roasted coffee, this water temperature is still acceptable, but for lightly roasted coffee, it is a bit low. Unless the brewing time is greatly extended and the grinding is fine, it will be difficult to obtain coffee. Adequate extraction.

The water temperature for making lightly roasted coffee on Qianjie is generally recommended to range from 90°C to 94°C. The specific temperature depends on the cooperation of other parameters. For example, the temperature used on Qianjie is around 92°C. The coarser the grinding and shorter the extraction time, the higher the water temperature used, and vice versa. After saying so much, everyone must be a little dizzy. So next, Qianjie will share the specific parameters and practices used by Qianjie through practical operations, which should provide some reference value to all friends ~

Brewing demonstration This time, the coffee beans brewed in Qianjie are Qianjie Yejia Shefi Guodin in the Doudan, because they not only have excellent flavor performance, but also have high density because they are planted in high-altitude areas and are lightly baked. It is very suitable for serving as the protagonist of this demonstration. The extraction parameters are as follows: amount of powder used: 15g powder-to-water ratio: 1:15 Grinding degree: 10 scale of Ek43, 75% sieving rate of No. 20 sieve, grinding and boiling water temperature of fine sugar: 92°C Cooking method: Three-stage use of filter cup: V60 Then first, we use twice the amount of water to steam for 30 seconds, which is 30ml of hot water.

After the steaming is completed, inject a second section of 120ml of hot water with a moderate water flow (water injection rate of about 4 - 5ml/s) starting from the center and outwards. Because the density of this bean is high, in order to prevent hot water from flooding the powder bed to form bypass water, we use a slightly smaller water flow, which can effectively extend the extraction time. It doesn't matter if we can't control the water well. We can divide the steamed water into three sections on average, so that we can achieve the same purpose. The water injection takes about 30 seconds (120ml of water injection). After the injection is completed, we just need to wait for the liquid in the filter cup to penetrate into the coffee powder where the bottom can be seen, and then we can start injecting the third section of hot water.

Similarly, moderate water flow is still used for injection in the third section. A total of 75ml of hot water is injected in this section, which is injected in a small circle around the center of the powder bed. After the injection is completed, we just need to wait for the coffee liquid to be filtered, and we can remove the filter cup and end the extraction ~

The total time is 2 minutes and 17 seconds, which is a little longer than regular brewing, but it doesn't matter, the main product of lightly roasted coffee beans is a durable extract!

Through tasting, we first felt the fragrance of lemon and jasmine, which was gentle and elegant. This is followed by the lively acidity and honey-like sweetness of the red berries, sweet and sour. After swallowing, you can clearly feel the aroma of oolong tea, which is long and clear. In short, we can try to be as bold as possible when brewing lightly roasted coffee beans, and don't have to worry about whether the coffee will be too extreme because a certain parameter is too extreme. Bitterness appears. The vast majority of lightly roasted coffee is really very resistant to extraction. Even if it takes a long time and is ground finely, it is difficult to produce an unflattering negative taste ~

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