A brief Analysis of the effect of Coffee Oil on the body and the reason for insufficient Oil extraction

Professional coffee knowledge exchange more coffee bean information please follow the coffee workshop (Wechat official account cafe_style)

Espresso is a small and delicate cup of coffee with rich golden coffee oil. It can be said that this layer of golden coffee oil is a major symbol of espresso, known in Italy as "Crema".

Espresso from Qianjie Coffee

What is coffee fat?

The oil of coffee is mainly composed of carbon dioxide and insoluble oil of coffee powder. It is well known that roasted coffee beans contain gases such as carbon dioxide. In modern Italian semi-automatic coffee machine extraction coffee, there will be a 9bar pressure to "squeeze" coffee pressed powder, coffee powder because of the pressure of carbon dioxide, water for carbon dioxide showed a state of supersaturation, so carbon dioxide can not be released, directly into the coffee liquid.

And in this process will emulsify the fat in the coffee, these fat will be wrapped in carbon dioxide, because it is lighter than water, all will gradually delaminate, golden oil will appear on the surface, very beautiful.

So what are the factors related to the richness of espresso oil?

1. Coffee beans

We know that espresso oil is made up of carbon dioxide and insoluble oil, which has something to do with the roasting degree of coffee and the kind of beans. The deeper the baking, the more abundant the oil and carbon dioxide. Coffee beans like Robusta will contain more oil, so the extracted espresso will be more rich in oil.

Qianjie coffee in which sunflowers with coffee beans and commercial coffee beans can provide rich coffee oil.

Sunflower warm sun with coffee beans

This is a flavor-oriented blend of coffee beans on the front street, consisting of 70% Honduran sherry coffee and 30% Essex plus sherry sun-tanned cherries. Honduras Shirley Coffee is rich in coffee fat, and this blend of coffee beans brings the flavor of sherry, vanilla, cream, chocolate and caramel.

Commercial blending of coffee beans

Brazil, Colombia and 10% Robusta are used. Classic taste, this blend brings rich grease and taste, with caramel sweetness, nuts and cocoa, dark chocolate flavor, sweet and sour balance, a little bitterness, a lingering finish. The coffee beans in the Colombian Huilan area have a pleasant sour taste, mellow smell, moderate acidity, rich sweetness and intriguing sweetness, while the coffee beans in the Brazilian Hillado region have a comfortable bitter taste and a very smooth entrance. Robusta is rich in oil. This commercial blended coffee is suitable for coffee shops and beverage shops of all sizes.

2. Extraction pressure

Generally speaking, the extraction pressure of the semi-automatic coffee machine is about 9bar, which is determined by the performance of the coffee machine. Now some coffee machines have the function of variable pressure extraction. The extraction efficiency is low at low pressure and high at high pressure. The higher the pressure, the easier it is to extract the oil from the coffee.

3. Flow rate / channel effect

The flow rate is the velocity of the coffee liquid, and the final goal of our extraction parameters is actually the result of a flow rate. Like normal espresso, you need to start dripping the first drop of coffee about the fifth second after pressing the extraction button, and the subsequent flow rate is relatively uniform. The speed of flow rate will directly reflect the question of whether the grinding degree and proportion are appropriate or not. If it takes more than 10 seconds (except pre-soaking) to produce the first drop of coffee, it is possible that the powder is too fine or the pressure is too dense. If the flow rate is too fast or jet phenomenon, it is too coarse powder, or the emergence of channel effect.

So what is the reason why there is no oil when extracting espresso?

Qianjie summed up some guest feedback and came up with several situations that are easy to occur:

1. Coffee powder is too coarse. Too coarse coffee powder leads to the flow of water too fast, coffee extraction is not complete, the oil is too thin, water and water state.

2. Lack of pressure. It takes the pressure of 9bar to extract rich oils. If you notice that your coffee is thin, you can check to see if it reaches the pressure of 9bar.

3. Coffee beans are not fresh. The oil of coffee is mainly composed of carbon dioxide and insoluble oil of coffee powder. And carbon dioxide will be released over time. If the coffee is not fresh, it contains less carbon dioxide, so it can't press the coffee oil.

4. Unreasonable extraction scheme. The Italian concentrated extraction scheme used in Qianjie is that the ratio of powder to liquid is 1:2 and the extraction time is between 25 and 28 seconds. It can be used for your reference.

For more boutique coffee beans, please add private Qianjie coffee on Wechat. WeChat account: kaixinguoguo0925