"Boss, please brew the coffee a little longer. I want a stronger coffee."
Front Street believes that this is a situation that many friends who work in coffee shops will often encounter. Some customers want to drink a cup of coffee with a stronger taste, so they occasionally make such requests to the store.
It’s not difficult to understand, because in the eyes of most consumers, coffee is just like other drinks. The more liquid extracted, the richer the taste. But unfortunately, under normal circumstances, the concentration of coffee does not increase as the liquid volume increases. Why? You can take a look at an experiment that Front Street often shares in articles.With the grinding unchanged, Front Street used the same amount of powder to extract three cups of coffee with different liquid weights, and then measured their concentrations and tasted their flavors.coffee beans: Sunflower warm Italian blended coffee beansGrinding scale：Galileo Q18 Scale 1.0Extraction liquid weight: 38ml, 45ml, 55mlfirst group：It took 30 seconds to extract 38ml of coffee liquid from 20g of powder, and it was measured.TDS valueis: 11.87%. coffeeThe flavor is dominated by sweet and sour berries and whiskey aroma, followed by the mellow aroma of butter cookies, and the aftertaste is the baking aroma of vanilla and hazelnut.Group 2：It took 35 seconds to extract 45ml of coffee liquid from 20g of powder, and the measured TDS value was: 10.24%. The flavor of coffee is caramel, cocoa, butter cookie, and whiskey aroma, with a little sour and sweet berry, and the aftertaste has the aroma of almond and a little bitterness.Group 3:It took 38 seconds to extract 55ml of coffee liquid from 20g of powder, and the measured TDS value was: 9.22%, which is the lowest concentration among the three groups. The flavor is not pleasant either. Although the above-mentioned flavors are present, they are all very bland, mainly barley tea and woody tones. It will have a slightly choking bitterness after swallowing.From the results of this experiment, we can see that when the amount of powder remains unchanged, as the weight of the coffee liquid increases, the concentration of the coffee does not increase but decreases. Why? Because the soluble content in coffee is limited.In a coffee bean, the substances that can be dissolved by water only account for 30% of the bean weight. After we have dissolved these soluble substances, no matter how much water is used for extraction, the concentration of the coffee will not be improved.Not only that, we cannot dissolve all the 30% of the flavor substances in coffee. Because in this 30% soluble matter, in addition to the sweet and sour taste that we like, there are also some unpleasant bitter, astringent, and miscellaneous flavors. If we dissolve them, the coffee will taste like the third cup, with obvious bitterness and throat-stuck astringency., and this is what we often call over-extraction.Therefore, in daily extraction, we will control the extraction parameters to dissolve only the flavor substances we need in the coffee beans. So, the question becomes, since this method doesn’t work, how do we increase the concentration of coffee?
It's actually very simple! We just need to reduce the amount of water used during brewing/the amount of coffee liquid extracted. Why? You can take a look at the color change of the coffee liquid during the extraction process of espresso or Pour over(V60) coffee.
The three extraction processes shown in the picture above in Front Street are the front, middle and last stages of coffee. It can be seen that the color of the coffee liquid is constantly getting lighter, and even turns white in the end. Front Street used three cups to pick up these three sections and taste their flavors separately.The first cup of coffee liquid tastes the richest and most concentrated among the three cups of concentrate, but the sourness is too prominent, which makes people feel a little uncomfortable; while the second cup tastes more balanced and has a moderate concentration; as you can see from the third cup, the color is the lightest among the three cups. It has a slight bitter taste when you drink it, the aroma is also very weak, and the taste is still thin.Both the color and taste indicate that the concentration of the coffee liquid becomes lower as it goes up. The reason is that a large amount of soluble substances in the coffee will be dissolved at the beginning. As the extraction process progresses, the soluble substances in the coffee will become less and less, so naturally, the concentration of the released coffee liquid will become lower and lower.So as long as we reduce the addition of low-concentration coffee liquid, the concentration of coffee can be improved. For this reason, reducing the amount of water injected or the amount of coffee liquid extracted has become the main means to increase the concentration of coffee.For example, Front Street uses a powder to water ratio of 1:15 when brewing Pour over(V60) coffee. If you want the coffee to have a higher concentration without changing the amount of powder, you can reduce the amount of water injected, such as adjusting the powder to water ratio to 1:14 or 1:13, so that the concentration of the coffee can be improved.However, it should be noted that the reduction in water volume will causeExtraction efficiencyDecrease simultaneously, if we want to increase the concentration while maintaining the same extraction rate(i.e. the amount of material dissolved), then it is necessary to improve the extraction efficiency of other parameters such as grinding degree, water temperature, time, etc. according to the actual situation. Not just Pour over(V60) coffee, but also espresso.Another thing to note is that the above method can only increase the concentration of coffee. And if what we want to improve isin milk coffee(or some other fancy coffee)coffeeFlavor intensity, then this method is not applicable! Because the material quality of the coffee itself does not increase, only the concentration changes, so this approach cannot amplify the coffee flavor in fancy coffee.If we want to increase the concentration of coffee flavor in fancy coffee, we need to increase the proportion of concentrate in it by increasing the amount of powder/decreasing the amount of milk or other materials, so that the flavor of coffee can be more prominent.
You can now buy the above coffee beans online at the Taobao store “FrontStreet Coffee” (前街咖啡). FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou, China, and its Guangzhou retail shop sells coffee beans only. The shop carries dozens of coffee beans from different origins around the world, including carefully selected single-origin beans for V60 pour-over and espresso. Guangzhou’s FrontStreet Coffee shop is recommended by many coffee lovers.
The FrontStreet 2013 Yunnan coffee beans sold in the store come from the Typica variety grown at FrontStreet Coffee’s own plantation in Yunnan. The name comes from the year the brand and the plantation were founded. You can buy these beans from China’s Yunnan origin at the Guangzhou shop and at FrontStreet’s Taobao store.
FrontStreet coffee beans are freshly roasted within 5 days and deliver consistently excellent quality and great value. Orders placed before 17:00 are shipped the same day, and most areas within Guangdong Province receive them the next day.
FrontStreet Coffee Taobao store: https://qianjiecoffee.taobao.com
Or search for “前街咖啡” (FrontStreet Coffee) on Taobao
Important Notice: FrontStreet Coffee has moved to a new address: 315, Donghua East Road, Guangzhou (coffee beans only)
Tel: 020 38364473
