Does air space in tea tins destroy tea?
Here’s something I’ve wondered for a while.
I am absolutely bonkers for washi tins. I would say I collect them but after amassing about 16 of them, I’ve told myself I’m at a good limit and should stop buying them.
Washi tins are metal tins wrapped in washi paper. They are very ornate, made specifically for storing tea, and come in many sizes: http://www.japanesehomestore.com/v/vspfiles/photos/Washi%20Tea%20Tin-3.jpg
Now my preference is to store tea directly in the tins. No-brainer right? They’re meant for storing tea. They have a plastic or metal internal lid that stays on underneath the outer lid to keep them airtight.
But I have always wondered… will tea become less fresh if there is a lot of air space in the tin? Like if it is half full or even only a quarter full? Is this producing opportunities for the tea to become “stale” as more fresh air and moisture have the opportunity to enter the tin each time it is opened? I live in Kansas, where humidity levels are very average and are good for humidity sensitive things like tea leaves and guitars. The local owner of Shang Tea company, who farms his own tea in China but runs his store here in Kansas, says the humidity here is not an issue as it is just the right levels.
Sometimes I keep teas inside their original foil pouch and put those into the tea tin for sort of a double protection, but I wonder if this is unnecessary. Aesthetically speaking, I prefer to just have the tea in the tin and to scoop it out each time I use it, not have to fumble with a bag that is tightly tucked inside the tin.
I feel like some of my teas have maybe lost a bit of their steam, so to speak, after months of storage in metal tins… a little less flavorful and fragrant than before, but maybe it’s just in my head. I noticed it especially with some Chinese green tea (I think). I’d like to know what others think about this as I’m not sure if I’m convinced it is really changing the tea, but it might be.
What are your thoughts on this? How do you store your tea, and do you know from experience or have a source that claims that metal tea tins can change tea flavor over time, or that air space in an airtight tin can be detrimental to the tea?
So far my “container teas” have been fine, but I don’t keep them open constantly and I use up the tea inside as quickly as I can. I much prefer to store my tea in the original packaging (which is usually a pouch) so I can gently squeeze out any extra air.
I’m not a big fan of tins. Oxygen and moisture are what causes the tea to age. If you just put the tea in the tin and don’t open it, the effects should be limited, but if you have 1 ounce of tea in a 1 pound tin and open it every day, you might as well store the tea in a bowl on the counter (IMHO).
Having said that, I like to use small one-ounce tins for my favorite teas, filling them regularly from the sealed bags, which I roll tightly to exclude as much air as possible when I open them (once a month or so).
I have tins, either from H&S or original tea. I do like to keep them in foil ziplock pouches. Takes less space. I group them by company and put them in clear boxes.
The only teas I have in tins are rooibos blends. One is still sealed in the original tin.
I tend to roll up the bag the tea came in and stuff it into a tin. One part, I can group similar teas into the same tin, another part easier tin cleaning.
I’ve been finding the tea does much better in a tin than the tea package not in a tin – especially small samples sizes. Little tea samples in those little ziplocks lose flavor quick!
I own a vacuum sealer (which I bought for freezing food storage and sous vide cooking) and I’ve been playing with vacuum packing samples of tea. Vacuum sealing the teas have turned out really well – even if I don’t vacuum the bag and just heat seal it the teas are like new when opened! I’m probably going to vacuum seal teas I have in larger sizes that I don’t get into often, and leave 1oz out.
I try to keep as little varieties in tins, like I’ll have four different kinds and try to use them up within a month or two.
Once I’ve opened the tea’s original foil bag, I keep it in the foil and put that in a tin (or a ziplock bag if all my tins are already occupied) – I fold the top over and hold it in place with sticky-tape. I always think that if I put the leaves straight into the tin, the tea would pick up a ‘tinny’ taste, but I’ve never tried it.
I think it depends upon the type of tea in the tin. In Japan, people are looking to keep sencha and gyokuro as close as possible to the original, fresh state. These teas begin to oxidize the moment their packages are opened. Companies like O-Cha use special bags to prevent or minimize oxidation, and the tea can be kept in the fridge too. Sencha/gyokuro need to be sealed off for sure.If other types of tea are losing fragrance, lack of humidity can be a factor because the tin is too sealed off. A clay “pouch button” used for fresh tobacco can be a solution. To test if lack of humidity is a factor, I wet and squeeze out a small bit of good quality paper towel, about 2 square inches, form it into a ball and put it in the tea for a few hours or a day and then smell the result. If my tea becomes more fragrant, then I know the dry air is the cause. This would be what I do for oolong and black tea.