お茶の旅
2020.07.03

Cold-Brewed Tea|A Pleasant Feeling of Coolness Spread into Your Heart

Cold-Brewed Tea|A Pleasant Feeling of Coolness Spread into Your Heart

This summer has been even warmer than before.

Cold-brewed tea could be a remedy for the scorching summer.


What is cold-brewed tea?

Cold-brewed tea is the tea that is brewed with only cold water or iced water and in longer steeping period of time.

If you brew the tea with hot water and leave in the refrigerator, it is not cold-brewed tea.


Is there a special tea for cold brewing?

No, different categories of tea require different length of time on cold brewing.

It is not like cold-brewed tea is tasteless; it is only because of the brewing time being too short.


What is the difference on tastes between cold-brewed and hot-brewed tea?

Hot-brewed tea has stronger taste with rising aroma. Most of the aroma molecular needs high temperature to be able to be noticed.

Cold-brewed tea has soft and sweet taste, with lighter aroma.


What kind of tea is suitable for cold brewing?

Fresh tea, high mountain tea, Oriental Beauty, and black tea.

Roasted tea can also be cold-brewed, but its brewing time needs to be doubled.


The method for cold-brewed tea

1. A bottle of cold water, with moderate amount of tea leaves. It will be fine if you put a little bit more.

2. Leave in the refrigerator for 4 hours.

3. Enjoy it!


What are the key points we need to pay attention to when making cold-brewed tea?

Cold-brewed tea is mostly likely being made in the summer time, and the amount you drink would be in proportional to the room temperature.

Therefore, you need to pay attention to the hygiene matters, namely “bacteria”.

1. When the cold-brewed tea has become cloudy and not transparent, please do not drink it anymore, because it means that there is already a large amount of bacteria growing in your tea.

2. When the cold-brewed tea has been removed from the fridge, please do not re-store in the fridge again.


How come the cold-brewed tea tastes smooth and sweet?  The hard science for cold-brewed tea

The composition for taste of tea mainly includes catechin (astringency and bitterness),

caffeine (bitterness) and amino acid (refreshing and sweet).

In theory, solubility is related to molecular mass. The larger the molecular mass is, the lower the solubility will be.

Catechin: molecular mass is 290.26g/mol; solubility is 0.1g/100ml/25.

Caffeine: molecular mass is 194.19g/mol; solubility is 2.2g/100ml/20.

Amino acid (L-theanine being the highest): molecular mass is 174.2g/mol; solubility is 25g/100ml/25.


From the above, we can notice that when brewing tea with cold water, the dissolved compounds are mostly sweet amino acid, and less bitter and astringent compounds.


This also explains why the taste of hot-brewed tea is stronger because its bitter and astringent compounds have been dissolved more.

Catechin: easy to be dissolved in hot water.

Caffeine: 67g/100ml/100

Amino acid: 67.2g/100ml/100


A salvation for bitter and astringent tea

When the teas are brewed with hot water and feeling too bitter or astringent, you could try the cold-brewed method.


#yoshantea #Cold-Brewed Tea