The influence of Italian coffee grinder on espresso

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Bean grinders are often directly ignored in coffee recruits! This is a really sad fact! Many novices buy coffee powder directly in the supermarket. But friends with a little common sense will know that the shelf life of coffee after roasting is very short. It is generally recommended that freshly baked beans should be drunk within 1 month! Because in a month's time, the elements in the beans that can bring you the ultimate flavor will be quickly lost. Coffee ground into powder oxidizes faster because of its larger contact area with air. Generally speaking, 15 minutes after grinding is enough to turn the original boutique coffee into waste.

Espresso requires the most fine grinding compared to other brewing methods (except Turkish coffee), which means that in order to get the same amount of coffee, espresso is much heavier than filtered coffee. When the boutique coffee shop offers more concentrated than filtered coffee, the load of the bean grinder will be very heavy, so there is a greater need for an Italian bean grinder for espresso. Coffee seedlings believe that if you want to make more than 60 cups of lattes in an hour, for example, if the amount of powder in a cup is 16 grams, an hour is 960 grams, and about one kilogram of coffee powder, the continuous operation stability of the knife plate is very important. )

Bean grinders are generally classified by coffee extraction, which are divided into two categories: single coffee grinder and Italian coffee grinder!

Italian bean grinder can be divided into two types: cone knife type bean grinder and flat knife type bean grinder. Both, like Ford versus Chevrolet, have their own supporters.

Whether you choose a cone knife or a flat knife bean grinder, in fact, all Italian bean grinders have two difficulties to overcome: temperature fluctuations and grinding residual powder. Friction produces heat, and when grinding and cooking espresso coffee beans, they keep rubbing because the coffee beans have to be ground very finely. Any barista knows that the temperature fluctuation caused by the Italian bean grinder will seriously damage the parameters of espresso coffee. During the peak period of operation in the morning, the brewing time will accelerate as the temperature of the bean grinder rises, so it can only stop running and let the machine cool.

One previous theory is that temperature fluctuations cause the cutterhead to expand and contract, but this theory has been overturned and cannot reach a temperature high enough to deform steel and titanium even at the hottest time of the bean mill. Recently, a theory has been put forward that there is a difference due to the change of coffee temperature. The lower the temperature, the easier the coffee beans are ground, and the finer the grinding. On the contrary, the higher the temperature of the coffee beans caused by the knife head, the lower the fineness. The lower the fineness, the faster the flow rate, which explains why continuous grinding can change the cooking time.

But no matter what category, my personal advice is to buy the best bean grinder that you can afford!