Some time ago, when Front Street was tinkering with a Moka pot in the store, a friend saw that the Moka pot brewed by Front Street was very rich in coffee crema, so he asked Front Street about the secret of brewing rich crema, because the Moka pot he brewed at home had very thin crema.
The same situation often occurs among users of espresso machines. Friends often report that the espresso they extract has no oil.Such problems are easy to solve. Because pressurized extraction cannot extract oil, in most cases it is caused by two situations. The first is a problem with the coffee beans, and the second is that the extraction pressure is not high enough.Whether it is the grease in a moka pot or the grease in espresso, their essence is not real grease, but a "milky foam".Under high temperature and high pressure extraction, the lipids of the coffee itself will be emulsified and dispersed in the water, and then wrap the carbon dioxide released from the coffee powder to form tiny bubbles. The coffee creme we see is an appearance composed of countless such tiny bubbles.So it is actually foam, called "Crema". However, due to translation or understanding problems, it is customary in China to call it "grease".There are two main conditions that determine whether the oil is rich or not, namely the coffee beans themselves mentioned in Qianqian Street, and the pressure during extraction.Reason 1 for the oil being too thin: the coffee beans used do not have too much carbon dioxideCarbon dioxide is the main filling material of bubbles, and its amount will determine the richness of the oil. When other parameters remain unchanged, when the coffee beans we use contain more carbon dioxide, the extracted coffee will have thicker oils. On the contrary, if the coffee beans contain less carbon dioxide, the extracted coffee oils will be relatively thinner.There are two main factors that determine the carbon dioxide content in coffee beans. The first is the roasting degree of the coffee beans. When the coffee beans are roasted darker, the carbon dioxide content is more, and vice versa; the second is the freshness of the coffee beans, when the coffee beans are fresher, the more carbon dioxide is retained, and vice versa.Therefore, when the coffee beans we use are not fresh enough, or the roasting degree is not dark enough, the extracted coffee oil will not be very thick.If we want to extract rich coffee oil, then we can choose to use some fresher or darker roasted coffee beans! For example, the Front Street Italian Classic/Commercial/Front Street Black Cocoa Blend (100% Arabica) in the Front Street Bean List is roasted darker, which can extract rich oils, and is more suitable for use with a Moka pot/espresso machine. Because the roast is darker, there is not much acid, and the espresso produced will not have an abrupt taste after being made into milk coffee.But what we need to know is that the richness of oil is not linked to the taste and quality of coffee. Because the carbon dioxide content, as mentioned before, has little to do with the quality of the coffee. Therefore, Front Street does not recommend it to everyone in many cases.unconditionallyGo for the richness of the oil, because it will not have a very intuitive impact on the taste of the coffee.Reason 2 for the grease being too thin: not enough pressureAs mentioned before, this golden layer of oil is a unique product of pressurized extraction, because only by applying higher pressure during extraction can the oil be fully emulsified and form a stable foam. When the pressure during extraction is not high enough, we cannot fully emulsify the oil, and at the same time, not much carbon dioxide will be released in a short period of time, and we will not be able to produce rich and long-lasting oil. Therefore, sufficient pressure is very important.There are many factors that can affect the extraction pressure. Without changing the extraction parameters of the coffee machine, there are powder volume and grinding. Among them, the grinding degree of coffee powder is the most critical factor in determining the pressure value. Why? Because the amount of pressure exerted by the coffee machine/moka pot depends largely on the resistance of the powder.The greater the resistance of the powder, the greater the pressure required for the water flow to pass through. At this time, the coffee machine will apply higher pressure for extraction, and vice versa. The main factor that determines the resistance of the powder cake is the grinding degree of the coffee beans. The finer the coffee powder is ground, the greater the resistance of the final powder cake, and the greater the pressure exerted by the coffee machine during extraction.In other words, when the oil you extract is not rich enough, but the beans are very fresh and roasted very dark, we can observe the liquid extraction speed. If the liquid discharge speed is very fast, it means that the grinding is relatively coarse. If you want to get a rich amount of oil, you need to finer the grinding to increase the resistance of the powder.But there are two points that everyone should pay attention to. The first point is that the grease mentioned earlier is not linked to the taste/quality of coffee. More grease does not mean that the coffee will taste better. The second is that when the coffee powder is ground to a certain level, the thickness of the grease will be reduced. Because the extraction speed is too slow, the formation of grease will be slowed down, relatively speaking, there will be less.So, the above are the main reasons why the oil extracted from Moka pots and coffee machines is not rich enough in our daily life. If you also want to extract a cup of coffee with rich oils, then you might as well see what adjustments you need to make~
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
