Can I use milk to make coffee by hand? Can milk be used to make coffee by hand? Is it good to make coffee with milk?

Recently, Qianjie discovered that many bloggers are sharing how to use milk instead of water to make coffee, saying that the coffee brewed in this way will taste good. As a result, friends often write privately to Qianjie backstage, asking what parameters should be used to make coffee with milk... To be reasonable, Qianjie had already shared it as early as last year, and this year it also shared the feasibility of using milk to make coffee. The conclusions of these shares are without exception: it is difficult to make "good coffee" with "milk". The reason is that milk is not suitable for making coffee. (Note: Just rushing)

Why is milk not suitable for making coffee? Why would Qianjie say it was not suitable? Because when we use milk to brew coffee, we face many restrictions, and the biggest problem is that milk cannot have enough extraction efficiency. It has no way to extract the flavor we need in coffee in a short period of time like water. The substance is flushed out completely.

Temperature limitations: First of all, temperature limitations! When Qianjie shares espresso, it often mentions that the temperature of hot milk should be around 65°C and not exceed 70°C. This limitation is not only because within this range, lactose in milk can be activated to make it more sweet, but also because once milk exceeds 70°C, some substances in its body will be destroyed due to excessive temperature, and the texture of milk will be reduced as a result (although the difference will not be too big, the taste will be thinner and the milk will not be so sweet).

If we want to get a cup of milk coffee with excellent taste and taste, then the temperature of the milk should not exceed 70°C. But as we all know, it is difficult for 70°C to dissolve the flavor substances in coffee in a short period of time, let alone milk. So the first difficulty in making coffee with milk is that if we want a perfect experience, we cannot use high-temperature milk to make coffee. However, if the temperature of the milk is not high enough, sufficient extraction efficiency cannot be obtained to completely dissolve the flavor substances in the coffee in a short period of time.

Limit on concentration: Even if we put aside the temperature limit and send the milk to 100°C to make coffee, we will not be able to make a pot of fragrant and delicious milk coffee. Why? Because its concentration is so high.

Qianjie often shares that concentration gradient is one of the core driving forces for extraction. The reason why hot water can quickly extract flavor substances in coffee is because the concentration of water is relatively low and has a large concentration between water and coffee powder. The concentration gap, so the flavor substances in coffee powder will quickly transfer to low-concentration water. As the concentration of water becomes higher and the concentration difference between the two becomes smaller and smaller, the rate of solute transfer will gradually decrease. The concentration of milk itself is very high, even much higher than espresso, so when we use milk to extract coffee, although the flavor substances in the coffee can also be dissolved, it is very, very slow!

Take Qianjie as an example. The picture below shows the coffee brewed on Qianjie with milk soaked coffee powder at 100°C. It took about 30 minutes to brew! Even if various methods such as stirring were added to increase the extraction rate, the final result was a pot of milk with a coffee flavor. Moreover, the coffee flavor was still a taste of insufficient extraction. It tasted astringent and was generally not good.

Well, we can know from this experiment that because of the extremely high concentration of milk, we cannot completely dissolve the flavor substances in coffee in a short period of time. What does it mean? You can use milk to make coffee, but the taste will not be too good. Unless you use immersion extraction, such as cold brewing coffee with milk, you can get a relatively complete milk extract coffee because of the long extraction time.

Restrictions on flow rate: Finally, restrictions on flow rate! The cup of coffee mentioned on the front street that was obtained by soaking coffee powder in milk for 30 minutes was not actually intended to be brewed at the beginning. It was hand-brewed coffee, that is, drip extraction. Then why did Qianjie later call it brewed coffee?

Very simple! Because the concentration of milk is so high, the time it takes to filter out from the filter paper is very long. Qianjie uses 225ml of hot milk to make 15g of coffee powder. At first, the milk dripping speed was relatively fast, but from two minutes on, the dripping speed became very slow. It is dripping at a rate of drop by drop. Then starting from 11 minutes, it takes a few seconds to drip a drop of milk coffee. Finally, after thirty minutes, Qianjie was impatient to waste any longer, so he used a carved needle to pierce the filter paper at the bottom, allowing the milk and coffee in the filter cup to quickly penetrate out. The price is that it is easy to drink a mouthful of residue during the tasting process. But even so, the taste of coffee is complicated and cannot be called delicious at all.

The extremely slow filtration speed changes the coffee from drip filter to soak, so this is not much different from making coffee directly with milk. If we want to increase the flow rate, we can only increase the gap by adjusting rough grinding, so that the milk can flow through the coffee powder faster, but this further reduces the extraction efficiency, and the coffee that comes out can still It can only be coffee-flavored milk. That's why Qianjie has always emphasized that milk is not suitable for making coffee. If we want to use milk to extract a pot of fragrant and delicious milk coffee, Qianjie still recommends making it by soaking. At least the soaking time is longer, and it can be stirred more vigorously to more fully dissolve the flavor substances in the coffee.

Finally, if you really can't help but try it, then it's best not to use a hand-flushing pot to hold the milk when trying, otherwise... Whoever tries will know ~~

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