How to Keep Your Matcha at Its Best
Good matcha is more sensitive than most people realise. Light, heat, air and moisture all degrade it, and the compounds that make a first flush ceremonial grade matcha worth buying are exactly the ones that suffer first. Here is what each one does and the simple habits that keep every bowl as good as the first.
What matcha is sensitive to
Four things degrade matcha faster than anything else, and understanding what each one does makes the storage rules easy to follow rather than arbitrary.
Light breaks down chlorophyll, the compound responsible for the vivid green colour of high-quality ceremonial grade matcha. Expose an open tin to natural or artificial light regularly and the colour fades measurably within days. The flavour compounds follow. A matcha left on a windowsill or a brightly lit kitchen shelf will look and taste noticeably different within a week.
Heat accelerates oxidation across all of matcha's key compounds, EGCG, L-theanine and chlorophyll. A kitchen shelf near the kettle, the oven or a radiator is one of the worst places to keep matcha. The ambient warmth during daily cooking is enough to accelerate degradation noticeably over a matter of weeks.
Air is the most common problem and the easiest to underestimate. Every time you open the tin and leave it unsealed, or reseal it loosely, you introduce oxygen that begins breaking down the powder. Matcha is ground to a fine particle size, around 10 microns for Master's Reserve, which means it has an enormous surface area relative to its volume. That surface area oxidises fast when exposed to air.
Moisture causes clumping and, in more extreme cases, accelerates the breakdown of the powder's structure. A damp environment or introducing a wet spoon into the tin will compromise quality quickly.
The answer is the fridge
There is one right answer for storing matcha and it is the fridge. Not a cool cupboard, not a dry shelf, not the pantry. The fridge.
The fridge provides the three things matcha needs most. A stable, cool temperature that slows oxidation. Darkness when the door is closed. And a consistent environment that does not fluctuate with the ambient temperature of your kitchen during cooking.
The one condition is that the tin must be properly sealed before it goes in. The risk of refrigerating matcha is condensation. If you open a cold tin and leave it out in a warm kitchen while you make your matcha, moisture can form on the powder. The solution is simple. Open the tin, take what you need, seal it, and put it back immediately. Once that habit is established, it takes about five seconds.
Do not leave the tin on the counter between uses. Do not store it near the kettle. Seal it and refrigerate it, every time.
How long it keeps
An unopened tin of Master's Reserve stored correctly in the fridge will hold its quality for around a year from the production date. Once opened, use it within four to six weeks for the best colour and flavour.
Store it correctly and it will taste as good on the last bowl as it did on the first. That is the standard it was produced to.
Master's Reserve is available now, delivered across the United Kingdom.