How do you drink black coffee? The Best Taste temperature of Coffee & can Coffee be reheated when it gets cold

It is not without reason that the phrase "drink coffee while it is hot" is often mentioned by everyone. In front of the street, I remember a brown friend described the cold coffee like this: "after taking a sip, my skull hurts, and the bitter / sour + wood taste lingers in my mouth, which makes me autistic for a long time." "

Why can hot coffee taste so bad when it is cooled?

Temperature changes taste performance and sensory experience.

In the front street, when testing a coffee bean to determine its flavor, it will be judged in three temperature stages: high temperature, medium temperature and low temperature, because the coffee liquid will have different flavor performance at different temperatures. There are two main aspects of this situation, one is that the taste substances of coffee change with the temperature, and the other is that the senses of the human body change with the temperature. Human senses can feel five kinds of taste substances, among which coffee most often shows three kinds of taste. The effects of these three flavor substances will be different with different temperature stages.

"bitter taste, bitter feeling"

In the world of taste buds, the sensitivity to taste and bitterness always rank first! So whenever the taste buds feel bitter, the taste buds will immediately convey such a message to the brain: "Let the nerves tighten up a little bit, ah, the pain is coming!" "

Bitterness becomes more pronounced as the temperature drops, because when the temperature is too high, the hot feeling of the liquid in contact with the mouth will overshadow the taste buds and reduce taste sensitivity. So when we taste the deeply roasted coffee beans, the high temperature can already feel the bitter taste, when the coffee is completely cold, it will be more difficult to taste.

Sweetness, sweetness

Sweetness is most obvious when the temperature of a food is close to the normal body temperature of the human body. For example, 🌰: add sugar to a cup of hot water and stir it well, then taste it at different temperatures. You will find that the sweetness is most obvious when the sugar water is at 30-50 ℃. Coffee liquid is the same, when the coffee liquid reaches this temperature value in the mouth, sweetness and sweetness are the most obvious.

"sour taste, sour feeling"

The sour taste does not show obvious difference with the change of temperature ~ it is also a cup of hot water put in lemon juice, no matter which temperature stage, the sour taste performance will not have obvious difference. Then why is the sour taste of the lightly roasted coffee unusually obvious after it is cooled? first, the bitter substance of the lightly roasted coffee itself will be less than that of the deep roasted coffee. As long as it is mainly sour and sweet flavor substances, when the temperature drops below 30 ℃, the sweet taste is no longer active, it will highlight the sour taste. Another one is about the oxidation of coffee oil.

Why does coffee have an unpleasant bitter / sour taste when it is cooled?

One is because the oil is oxidized. Although the filter paper blocks most of the grease in the brewing process of hand-brewed coffee, a small part of the oil will melt into the coffee liquid and drip through the filter paper. As the temperature of the coffee liquid drops, this layer of coffee oil will slowly re-condense and float on the surface of the coffee liquid to come into contact with the air. After direct contact with air (oxygen), this layer of oil will begin to deteriorate and produce a strong sense of acidity (more in light roasted coffee), and this perishable layer of oil is also a source of fuel consumption (more in deep-roasted coffee).

The second is because the pigment is oxidized and polymerized, which is simply a coffee stain. Coffee beans in the roasting process will produce brown pigment because of the caramelization reaction, some of the substances from caramelization will bring caramel, chocolate and other flavors to the coffee, and this part will oxidize and deteriorate over time, and the taste will gradually become bitter.

The best tasting temperature of coffee

Just mentioned above, with the difference of coffee temperature, the taste and flavor performance will be different at the best time. Freshly brewed coffee is usually more than 70 ℃, so it is difficult for us to take a sip at this time, so we can smell the fragrance first. Volatile flavor compounds are the most active at high temperature. When the coffee drops to 60 ℃, it is the best time for mellow taste.

When the coffee drops to 50 ℃, when the sweet and sour substances are active, the high-quality flavors such as flower and nut flavor will be the most prominent at this stage. When the coffee drops to 37 ℃, the sweetness will be the best. The sour taste is strongest when the coffee is brought down to room temperature. Different coffee beans will have different best tasting temperature with roasting. Generally, the best tasting temperature of sour and sweet coffee beans is about 30-50 ℃, and the best tasting temperature of high alcohol thickness is about 40-60 ℃.

Can you reheat the coffee when it gets cold?

Qianjie is not recommended to do so. As the temperature drops, the volatile flavor compounds will be exhausted, and reheating will not restore the original aroma of the coffee. And when the coffee becomes cold and has an unpleasant flavor, reheating will only aggravate the performance of these flavors.