Following on from the TDS intro event earlier in the year the guild wanted to have a practical Research and Development event with a focus on different grinders and their effects on TDS and flavour/taste.

This was the first event since merging the guilds together, so we thought it was fitting that we created a learning platform for your QC team, so roasters and baristas could work and learn together!

There have been many developments in grinders in recent years, we assessed 3 common industry grinders discussing their design and practical application for espresso, and weighing this against their performance in flavour and extraction percentage. Note: different ages of grinders were used around the country so no definitive scientific information was gathered, also there are soo many variables in the final cup.

This was a tasting event to show how different grinders can effect flavour and how the extraction of the coffee can be effected by the grinder, hands on TDS testing was also be a focus giving you a chance to put some of the information from the last event into practise.

The events ran week of 11th July, in Auckland, Wellington & Christchurch using the same coffee.

EK43 V’s Kony V’s Mythos

The events were a great success around the country and ended up being quite technical, with many aspects of design and application being discussed.

Many of the attendees were surprised at the results of the extraction % with Kony coming out tops at all 3 centers! But this shows exactly why these tests are valuable, reality is very complicated, and assumptions are the mother of all, so getting to the bottom of what is actually happening on any given day is the goal, and why we ran this experiment. Also the Kony being the only conical burr set in this experiment may have had something to do with it. The range between top & bottom here was also very slim.

We assessed flavour from each grinder blind, and ended up with different flavour preferences in each center, Christchurch preferred EK, Wellington Kony, and an even split between the three in Auckland. Also note here, the water used in each centre may have dramatically affected the taste and also the extraction yield. Once you start to delve into & break down the aspects more and more questions can be asked and variables come into play, never mind the espresso machine & temperature!

We also refracted shots from each grinder with fairly consistent extraction % results nationwide.
Kony was the highest peeking over 21% in each center which was a surprise, Mythos averaged out at 19.5% extraction, and Ek43 with around 19-20% extraction. There are many reasons why this could be…. As noted above.

We dialed in each grinder to the same parameters rather than dialing to achieve the best TDS or flavour on each grinder, and this experiment would have different outcomes with a different coffee or dialed into different parameters etc.

While this event ran well and had fairly consistent results, further tests in a different situation may have different outcomes.

The purpose was to showcase a research and development project with a TDS/taste focus, rather than pitch a conclusive outcome on which grinder is best, as they each have respective qualities and practical applications for different situations and all have our own favourites ;-] René

Co-Chair Barista/Roaster Guild