Japanese Sencha is my preferred choice of tea in the warmer months.
Yes - it is lovely to drink in the colder months too, but I feel the best of Sencha is extracted when brewed with cold water.
After consuming 1 or 2 cups of cold brewed Sencha tea, I really feel relaxed, refreshed and replenished ...and there's actually science that explains why.
Green tea has different tastes and physiological functions depending on the temperature of water when it is brewed.
If you brew Sencha for too long - like 3-4 minutes you'll notice a very astringent and bitter taste.
This is because boiling water does a better job at extracting compounds such as epigallocatechin gallate (EGCG) and caffeine.
In contrast, cold water brewed Sencha has far less bitterness and astringency than hot brewed Sencha, and this is because Theanine and epigallocatechin (EGC) are easily extracted in cold water and these are the compounds which are directly responsible for the sweeter and richer notes of Sencha tea.