Why is the tongue numb when drinking coffee? And a little knowledge of the taste of the tongue

Professional barista communication, please pay attention to coffee workshop (Weixin Official Accounts cafe_style )

Fans often come to ask a lot of coffee related knowledge. One of them is: Why do some coffee make your tongue numb?

Let's put aside the external factors such as tongue being scalded and just eating spicy hot, and we will pull the answer back to the essence of coffee. Note that before you see the answer, please remember that coffee taste itself is a subjective opinion, such as I think some red wine is sour, but the bartender thinks it is acceptable, but it is sweeter.

I just want to share coffee with you and hope you can enjoy coffee!

To begin with, we have to rethink the taste map of our tongue. There are many taste buds on our tongue, and those white protrusions on our tongue are the papillae, fungiform papillae. The taste buds are buried in these papillae. In 1957, Shintaro Kodama and Akira Kuninaka, students of Kikumae Ikeda, discovered two other umami inducing substances in bonito fillets and shiitake mushrooms: nucleotides IMP and GMP, which led to the invention of high umami essence. It was not until 1985 that the scientific community officially listed umami as the fifth taste.

I'm sure you've all seen this map of tongue taste distribution, but here's a little supplement for you to know, Harvard psychologist Edwing G. Boring mistranslated a paper by German scientist David P. Hänig published in 1901, and incorrectly depicted this map of tongue taste distribution, but this map was later included in textbooks, so many people now think that different parts of the tongue can taste different tastes. In fact, the truest statement is that every position of the tongue can taste these five tastes.

Okay, back to the subject of the article,

Why do some coffees tingle the tongue?

Here are some of the possible reasons:

1. Not picking out defective beans or small impurities from raw beans, thus affecting the taste

Before roasting coffee, we will select the green beans well and pick out the bad coffee beans. If we don't do this action, it will affect the taste.

2. Improper control of the damper during roasting allows the smoke of roasting to remain on the coffee

When roasting coffee, if the damper is not properly controlled, the roast smoke may stay on the coffee, thus affecting the taste of the coffee.

3. Effects of baking techniques

The astringency of coffee comes from tannic acid in coffee. If soluble tannic acid is not successfully converted into insoluble tannic acid during roasting, the bitter taste will definitely be extracted!

4. Effect of extraction on brewing process

Coffee beans contain only 30% of the total substance in water-soluble substances, the remaining 70% is composed of insoluble fiber and carbohydrates. About 20% of the water-soluble substances give coffee a good flavor, while 10% of the soluble substances give it a terrible taste. Over-extraction can lead to unacceptable bad flavors in coffee being extracted and turned into a tongue-tingling bitterness.