Prufrocker: The Blog

The Future of Tea In Cafes

Depending on how you look at it this is a world’s first. I’m not talking about matcha but rather Stonerolled (TM) roasted green, oolong and black tea. But having mentioned matcha I must point out the Chinese emperor was putting yak’s milk in his matcha over 1000 years ago so this concept is not without... Read more »

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Depending on how you look at it this is a world’s first. I’m not talking about matcha but rather Stonerolled (TM) roasted green, oolong and black tea. But having mentioned matcha I must point out the Chinese emperor was putting yak’s milk in his matcha over 1000 years ago so this concept is not without precedent.

On the menu at Prufrock on your next visit you will see the sign, Stonerolled tea with milk, 4oz, 6oz, 8oz. Stonerolled is a registered trademark of London’s beloved Postcard Teas. For the last two years this wonderful tea company has been developing a range of tea suitable to be brewed just like matcha and blended with warm milk. Tim D’Offay from Postcard and I have spent a few sessions developing the recipes for Prufrock’s menu and we are delighted to invite you to a launch party for this new product on the 26th. Here’s some of the world’s firsts you will encounter that day.


All the teas we are using on Prufrock’s Stonerolled menu are roasted…In London! We will be offering roasted green (very usual), oolong, and roasted stone ground black tea (totally unheard of) and will be serving them mirroring our espresso with milk menu, 4,6,8 i.e. cortado, flat white, latte. This is also thoroughly unprecedented. Six years ago a lovely lady from West London fresh off the boat from a stint in California, came on a training at Prufrock. She brought with her some matcha powder and we made seaweed tasting lattes straight outta Wicked (the musical) all afternoon and it was very fun. Now I’ve noticed matcha has good traction on menus and a fairly expensive £3.50 powerful green umami-in-a-cup matcha latte is readily available. What’s different about this new product is how much more attenuated to the speciality coffee movement it is.


The range from Postcard includes three unroasted teas with more umami flavour but there was no doubt in my mind that the roasted flavour was what we wanted. (I’ll answer your questions on how Tim is roasting the tea in a little interview below.) The black tea literally tastes like a coffee. It’s compact, powerfully aromatic, a dream for efficient dosing and ground at such low rpm the shelf life of the ground product is comfortably 4 weeks with high aromatic intensity.


Let’s get the grinding discussion underway. You have seen traditional Turkish coffee mills? The burrs are made of stone which means no cutting surface, so beans are pulverised rather than cut which means particle sizes in the 15um region. But to make sure they go even finer, the rpm is crazy slow. Postcard’s custom made mill set them back £10k and runs at 33 rpm. This they claim (and I’m totally persuaded), preserves aromatics for much longer. Presumably due to the the very low level of heat built up with such slow grinding.


The quantities you are looking for to approximate the kind of flavour intensity you get in a flat white are somewhere between 1.2 and 1.8g of tea. You will be delighted to hear that a level metric half-teaspoon gives reliably 1.4g This is where we’re at. Tim recommends 85 deg C water temp and the brew ratio we will start with is 1.4g of tea to 20g of water. If you want a workflow efficient option here, a level imperial tablespoon holds 17g of water and a metric one does 15ml so that makes a surprising tidy prep method. It’s not been in Prufrock’s habit to follow the path of least resistance but the very nature of dosing something so tiny and finely ground lends it to volumetric dosing rather than a scale and I tested ten half teaspoons in a row and and every one was 1.4g. Clumping has not been an issue at all with any of the teas which I’m imagining is making the volumetric dosing so consistent. So I’m guessing the low RPM granite rollers are helping reduce this.


We are serving in Fernandez and Wells style Duralex glasses (the round bottomed ones) not just to spare the ceramic cups the indignity of having their glaze scratched off with a stainless steel whisk but also because the glass thing is Postcard Teas endorsed. They are very thingy about their cups but with this product they encourage glass. Dissipates heat faster? 


Let’s talk about roasting. A tea roastery in London is another world first. These teas are roasted at temps up to 180 deg C but here we encounter a cultural clash. There’s magic in tea. Daoism for starters which brings with it a belief in instinct brewing so they keep things like roast time a trade secret. Not something you third-wavers have encountered for a while but letting go of the good old days of secret blends with people thinking you’re an artist comes with a mild sense of loss. What’s interesting about the Stonerolled brand is I see it getting rolling (😀) more in the speciality cafe scene than the traditional teashop. 


We are kicking off ordering 150g of each tea at a time to preserve freshness and storing in vac canisters. But I have noticed no deterioration of aroma over two months.­ I made some samples for Andrew Tolley of legendary Taylor Street Baristas and he commented, ‘this is the future of tea in cafes.’ and I’m pretty sure he’s right. Here’s a list of pros. There’s no cons ;D.


  • It is utterly delicious. Nicer than matcha because it’s not all about umami, it’s about just the same kinds of flavours we appreciate in roasted coffee.
  • All the The Stonerolled tea is produced without pesticides. You will see below tea tends to be more resistant to pests making it a good deal easier to produce and hardier in its very nature as a leaf rather than a berry. But as the customer is ingesting the entire leaf, they need not feel any concerns about their health on a chemical level.
  • You can do amazing latte art in this product.
  • The entire leaf is consumed so there’s nothing to wash.
  • The quantities where shipping is concerned are literally 10 times lighter so it’s a less carbon intensive product to shift. You can’t achieve the same results by grinding yourself on a Turkish burr and then mortar and pestle. I’ve tried. I ended up massively more coarse still than postcard are able to go. Their grind is so fine, I tried to sieve it but it just literally gummed up my sieve like a paste.
  • A micro-con, barely worth mentioning is that the final sip has some larger particles but I’m good with this. Not in the league of a Turkish coffee by many fathoms. I make my Turkish coffee with about 12-70g so what I’m talking about is 10 times less of an issue than Turkish coffee. Just resist the final sip.


A comment from Prufrock GM (and two time UK Roasting Champ Matthew Robley-Siemonsma) says it all for me. ‘The reason it works is that it’s an incremental departure from the familiar. It’s new but it’s only one step away.’

It’s so easy for us to deliver that product in a speciality format. The dosing, the grinding, the preparation just fall into place along side our coffee menu and it is barista friendly. It has the flavours and the method of preparation we love. So awesome in fact the multi-location varieties trials from WCR could start including some camellia sinensis strains because it’s as good as coffee and this from a person who for a long time has said, I don’t have time in my life for more than one drink.


Last glowing point I would like to make is that Postcard are presenting these teas at the launch party for Stonerolled at Prufrock on the 26th where Tim with Postcard legends Jonathan Nunn and Alex Simpson (Alex is the roaster; London’s first Tea Roaster) will deliver a talk, Prufrock will brew up samples and we will have some refreshments with Postcards compliments with which to toast a turning point in European tea service. You’ll love it.

Here’s a little fact checking I did with Tim by email and his answers are so succinct I thought I’d just publish the whole thing word for word.

Prufrock: Is tea production easier and more resistant to fungus and pests than coffee. (coffee is very unresistant if you don’t know much about the leaf rust issue)

Postcard: Tea is possibly more resistant to pest and fungus than coffee. There are mites that attack tea plants and also scale but nothing as severe as coffee leaf rust. Remember tea took over from coffee in Sri Lanka after the coffee rust virus in the 19th century.

Prufrock: How is teas biodiversity? (98% of all coffee genetics still in Ethiopia so very inbred is coffee.)

Postcard: Tea is pretty biodiverse especially as until recently almost all tea was seed grown or grafted but for about 60 years most tea has been grown from clones / cuttings and this has lead to certain clonal cultivars becoming dominant. However there is biodiversity over many different Asian regions and countries.

Prufrock: Could a coffee farmer grow tea? (Coffee’s ideal temp range is 16-24 deg C at around 1300-2500m.)

Postcard: I have seen tea growing very close to coffee in south India on the same farm so it is possible. They also grow high grown coffee in Taiwan at similar sites to high grown tea but generally tea is grown at lower altitudes. 1300-2500m is very high grown tea. The temp range is fine and would enable all year round tea growing. I guess the main difficulty would be the equipment and knowledge needed to process tea as it leaves the farm as a finished product unless the tea farmer just grows the leaves and sells to a local factory.

Prufrock: What temps do you roast to? up to 180C max for London less for other roasting.
How long is a typical roast profile? Aaah trade secret but not long. When a Chinese tea maker roasts his oolong over charcoal he may roast for as long as 8 hours but at a low temperature of around 80C.

Prufrock: Is pre-ground tea like pre-ground coffee with volatiles escaping more easily or is it a bit different? seems different.

Postcard: It does seem different. Traditionally you grind or have your matcha used in Japanese tea ceremonies ground on the day or the day before you use it. Ideally you use all stoneground teas asap and certainly within a couple of months.

If these answers give rise to more questions please feel free to ask.

Speak soon and thanks again for all your help and support for stonerolled tea,



(Prufrock: What a guy!)