This Exact Water Temperature To Use For Perfect Homemade Matcha Every Time - Tasting Table
Briefly

Matcha should not be treated like a tea bag; boiling water can scald the leaves and lead to a bitter taste. Instead, use simmering water.
The quality of matcha varies significantly; ceremonial-grade is preferable and should be priced around $15 per ounce or more, preferably made in Japan.
Proper storage of matcha is crucial as it can't be simply put in the fridge; specific steps should be followed to maintain its quality.
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