Matcha Particle Size

私は　抹茶と　饅頭が　好きです!  (“I like matcha and manju!”)

A vibrant green colour with a slight vegetal smell, this powder is not a sample we commonly receive in the UK application labs.  But then, I am not in the UK.

抹茶は　みどりのパウダー　です。私は　日本　に　すんでいます。
(“The green powder is matcha.  I am living in Japan.”)

My “day job” is working as an application specialist in the development team for the imaging products, based in the UK headquarters.  However, my current occupation is working as an applications scientist in the Malvern Japan labs.  I was given the exciting opportunity to move to Tokyo on secondment, in the first instance to provide cover in the application labs whilst Aiko-san went on maternity leave, but crucially also to gain an insight into one of our most interesting and diverse application markets.

As a development team, feedback from those “in the field” is a vital source of information on how we should develop our designs and ideas.  By being placed directly in that environment, I have the enviable chance to get first-hand experience of the wide range of applications that our instruments are used in, and the variety of samples customers want to measure.

Matcha is one such sample.  But despite the outwardly unusual appearance of this famous Japanese green tea, the underlying powder characteristics required are familiar.

From a process point of view, a high degree of circularity is required to ensure good powder flowability.  From a mouthfeel perspective, to achieve a smooth and rich taste a fine particle size is necessary.  But one final requirement is (perhaps) unique to matcha.  Unlike your morning brew of Yorkshire Tea (or indeed the vast majority of teas), matcha is not steeped in hot water.  Instead, it is whisked using a bamboo implement called a chasen, which adds smoothness to the drink.  The whisking leads to the formation of a foam and in order to achieve good foaming properties, the powder particles should have a small diameter (10-15 µm) and a high degree of circularity.

I have only drunk matcha once since being here in Japan (plenty of ordinary green tea, of course, but matcha is the premium stuff only drunk on special occasions).  After visiting a customer to discuss their application feasibility results, we stopped off at a nearby castle.  After exploring the castle (and collecting my castle stamp), we stopped by the tea room.  Not the usual National Trust fare (alas, no cake…), but something altogether more rewarding.  We sat in the open air tea room, overlooking…um, Japanese-style gardens…and our matcha was brought out in small, wide-rimmed bowls, accompanied with a manju sweet (a type of wagashi, or Japanese confectionary).  Small wagashi are traditionally eaten with matcha, and this was no exception.  Manju are a type of flour cake, usually filled with anko (red bean paste) and its sweet taste balanced the slightly bitter matcha well.

And so we come to the title of this blog, 「私は　抹茶と　饅頭　が　好きです」, or, “I like matcha and manju”. It was in this tea room that Oyoshi-san came up with the idea of using this line as an ice-breaker for customer meetings: so after I introduce myself, I follow up with saying the broad equivalent of “I like tea and biscuits”… Of course, only to be said when appropriate and when given the secret signal… (“80% of my customers will smile…20% will be…confused”) Performing monkey? Absolutely. And only too happy to oblige.

I can’t understate how welcoming the Malvern Japan team have been towards me.  I could write a whole separate blog or two on how they have taken me under their collective wing.  Helping me set up my flat, shopping for furniture, inviting me to dinner, playing futsal, inviting me into their homes, climbing mountains, sightseeing, cycling tours… They have given me so much of their time.  Nothing is ever too much.

私は　日本の　同僚の　おもてなしに　感謝してます。(“Thank you to my Japanese colleagues for your wonderful hospitality.”)

So, what’s up next?  Well, we have The Ceramic Society of Japan conference coming up in March where I will be presenting some work on how the Morphologi G3-ID can be used in characterizing artificial diamond for use in abrasives manufacture and some of my colleagues will be demonstrating how various elements of the spray drying process can be characterized using the Morphologi G3, Insitec and the Zetasizer – so watch this space!  But now, I think, time for a cup of tea…

私は　抹茶と　饅頭が　好きです、でも　紅茶と　チョコレート　Hobnobs が　大好きです。
(“I like matcha and manju, but I love tea and chocolate Hobnobs.”)

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