VST CoffeeTools Settings Calculator

After my post V60: Drip or Immersion on VST Coffee Tools? questioning which settings to use on the VST App, I thought i’d take it one step further and develop a calculator that would allow users to work out the settings for their particular brew method.

You can find the calculator here. This calculator works for Pour Overs, Clever Drippers, Aeropress and Batch Brewers. It allows you to pop in the particulars of your brew and it will spit out an Adjusted LRR that will give you the most accurate EXT %. 

All you need to do is prepare a brew using your technique and measure the following:

Dose (g) – Mass of the dry grounds in grams.

Brew Water Weight (g) – The weight of the water you are starting with. This calculator is assuming its at 90+ degrees, similar to the app.

TDS of the last 10g (%) – as you get to the end of your brew, capture the last 10g or so to come through and take a measurement using the Refractometer. Also measure the weight of the pulled sample to add to Beverage Weight

Beverage Weight (g) – The weight of the final beverage. Combination of the cup and the sample pulled for the TDS of the Last 10g

From these numbers the calculator will work out the Actual Liquid Retained Ratio (LRR), and also the Adjusted LRR. This Adjusted LRR is then placed into the app. When you place this Adjusted LRR into the app it will give you an Extraction Yield % that is now accurately taking into account the extracted coffee that still remains in the coffee bed. Both MOIST and CO2 should be returned to Zero, in my view if you can’t measure it you may as well leave it at Zero.

Feel free to shoot across any questions.

 

 

V60: Drip or Immersion on VST Coffee Tools?

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Drip, dah! Obvious right? well maybe not.

If you are using a “traditional” technique that calls for staged pours, maybe 50g at a time, then Drip setting will give you the most accurate EXT %. However things are a little more complicated in my experience if you are using a technique advocated by Scott Rao and the likes of Matt Perger (watch video here). This technique in contras involves a small “pre wet” followed by the rest of the water dispensed in one complete pour.

Why the difference?

Well it all comes down to assumptions the app makes regarding the nature of the liquid retained by the coffee bed. With traditional drip coffee, fresh water is always passing through the bed and if one was to measure the liquid coming out of a V60 at the end of a brew, say the last 10g, it would have a very low TDS. It can be assumed then that the liquid retained by the bed is just water and can be discounted. Any calculations need only take into account the Dissolved Solids in the cup.

In a full immersion brew, lets take a plunger, after 5 minutes if one was to pour out the plunger and take a measurement, we’d have to consider not only the liquid in the cup but also the liquid retained by the bed. Why? Well, because the grounds were in contact with the brewed coffee so the liquid in the bed would be saturated with the same amount of dissolved solids (as a %) as the cup.

Lets break this down and take a look at the maths behind the VST App. Below is an example of a V60 using Drip and a Plunger using Immersion. The Liquid Retained Ratio (LRR) is left as the app default, C02 and MOIST are “0” to make the math simpler for this demonstration.

VST APPS for Android
Presets: LRR = Default, CO2=0, MOIST=0
V60
Dose (g) 12 From Scale
Beverage Weight (g) 200 From Scale
Cup
TDS % 1.25% Refractometer
TDS (g) 2.50 1.25% x 200g
EXT % 20.83% 2.5g/12g
Liquid Retained
Liquid Retained Ratio 2.10 Assumed by App
Liquid Retained (g) 25 2.1 x 12g
TDS% of LR 0.00% Assumed by App
TDS (g) of LR 0.0000 1.25% x 30g
EXT% 0.00% 0g/12g
Combined TDS (g) 2.50 2.5g + 0g
Total EXT% 20.83% 20.83%+0%
PLUNGER
Dose (g) 12 From Scale
Beverage Weight (g) 200 From Scale
Cup
TDS % 1.25% Refractometer
TDS (g) 2.50 1.25% x 200g
EXT % 20.83% 2.5g/12g
Liquid Retained
Liquid Retained Ratio 2.50 Assumed by App
Liquid Retained (g) 30 2.5 x 12g
TDS% of LR 1.25% Assumed by App
TDS (g) of LR 0.375 1.25% x 30g
EXT % 3.13% 0.375g/12g
Combined TDS (g) 2.875 2.5g + 0.375g
Total EXT % 23.96% 2.875g/12g
So back to the “Rao Method”*, in recent experiments it was found that the liquid that is coming out at the end of the V60 is of a concentration very near to the concentration of the cup. Here is an example of our readings below.

RAO METHOD
Dose (g) 12
Beverage Weight (g) 200
Cup
TDS % 1.25%
TDS (g) 2.50
EXT % 20.83%
Liquid Retained
Liquid Retained Ratio 2.50
Liquid Retained (g) 30
TDS% of LR 1.02%
TDS (g) of LR 0.306
EXT % 2.55%
Combined TDS (g) 2.806
Total EXT % 23.38%
This means we are much closer to immersion than drip ie 23.38 compared to 23.96.
So what now? Well we can hack the system slightly by adjusting the LRR. If we run a liquid retained ration of 2.04 it will give us the same reading we get manually so or our particular method it gives us an accurate indication of the Extraction Yield**.
Has anyone else had conflicting experience? Feel free to question my numbers, happy to be shown i’m wrong if that happens to be the case.
*My name not his

** How does this work? The TDS of the liquid retained in our V60 was 0.306g rather than 0.375g on the Immersion example. This is 81.6% (0.306/0.375g*100). So if we can take the default Liquid Retained Ratio of  2.5 for Immersion and scale it down to 81.6% of its value we get 2.04. So if we adjust the LRR to 2.04 instead of 2.5 on Immersion, this will do the job of tricking the app to say the bed now only retains 0.306g of coffee.

Scott Rao in Melbourne

Coffee Kaizen and Small Batch are  pleased to be able to offer the coffee professionals in Melbourne the opportunity to hear Scott Rao present masterclasses on Manual Brewing and Roasting.

Scott has a wealth of information to share from his almost two decades of experience as a barista, roaster and consultant. We really appreciate Scott’s approach to coffee; he has a very deep understanding based on sound investigation yet he is able to distil his findings into simple, useful suggestions that anyone can integrate into their production.

We hope you take the opportunity whilst he is here to come and learn from him, he will be presenting the following sessions:

Scott Rao on Manual Brewing – Masterclass Sunday, 23 March 2014 from 10:00 AM to 12:00 PM (More info)

Scott Rao on Roasting – Masterclass Sunday, 23 March 2014 from 1:30 PM to 4:30 PM (More info)

All the details are on our Eventbrite Page , please email us with any questions.

To stay informed about future coffee events in Melbourne please join our mailing list.

Scott Rao in Sydney

Coffee Kaizen and Mecca Espresso Ultimo are  pleased to be able to offer the coffee professionals in Sydney the opportunity to hear Scott Rao present on Espresso, Manual Brewing and Roasting.

Scott has a wealth of information to share from his almost two decades of experience as a barista, roaster and consultant. We really appreciate Scott’s approach to coffee; he has a very deep understanding based on sound investigation yet he is able to distil his findings into simple, useful suggestions that anyone can integrate into their production.

We hope you take the opportunity whilst he is here to come and learn from him, he will be presenting the following sessions:

Scott Rao on Espresso Thursday, 27 March 2014 from 6:00 PM to 8:00 PM (More info)

Scott Rao on Manual Brewing – Masterclass Sunday, 30 March 2014 from 10:00 AM to 12:00 PM (More info)

Scott Rao on Roasting – Masterclass Sunday, 30 March 2014 from 1:30 PM to 4:30 PM (More info)

All the details are on our Eventbrite Page , please email us with any questions.

The Science of Coffee Extraction for Ultimo Science Festival

We are honoured to once again be asked to offer a series of classes for the Ultimo Science Festival.

This year we will be presenting The Science of Coffee Extraction, a one hour exploration of the foundations of what is happening when we brew coffee. Through a series of tests and demonstrations, we will give you a better understanding of coffee brewing fundamentals and explore what influences the extraction and most importantly the taste of the beverage

Especially for those who love coffee, or otherwise for anyone who would like to further their sensory skills.

Science of Coffee Extraction will be presented by Sam Sgambellone and will run at 10am and 1pm on Saturday 21st of September. You can book your ticket using the form below or visit our Eventbrite Page for full details.

 

Science of Coffee Flavour for Ultimo Science Festival

We are honoured to once again be asked to offer a class for the Ultimo Science Festival.

This year we will be presenting The Science of Coffee Flavour, a one hour exploration of the foundations of what is happening when we asses the flavour of coffee. This hands on workshop will feature a series of tests and demonstrations which will give participants a better understanding how they perceive tastes, aromas and flavour.

Especially for those who love coffee, or otherwise for anyone who would like to further their sensory skills.

Science of Coffee Flavour will be presented by Sam Sgambellone and will run at 10am and 1pm on Saturday 14th of September. You can book your ticket using the form below or visit our Eventbrite Page for full details.

 

 

Perger and Kaminsky

We are pleased to be hosting new Australian Barista Champion Matt Perger and his main man Ben Kaminsky for a public talk and Masterclass.

Matt and Ben will be sharing their thoughts on the possibilities of espresso, and were they think it may be heading in the future.

To find out more, or to book your spot, visit our Eventbrite page:

http://espressotalk.eventbrite.com/

http://espressomasterclass.eventbrite.com/

January Class Schedule

 

Coffee Kaizen is offering a range of coffee classes in January that appeal to home barista all the way up to seasoned professionals. Kaizen prides itself on offering small group, industry relevant education sessions that provide the participants with real tools for improving their coffee making.

Getting the most out of your home Espresso Machine
19th of January, 9am. Mecca Roastworks, Alexandria.
This 3 hour class is designed to give the home barista a chance to get the most delicious results possible from their home machine. This class is run by Tuli Keidar, Mecca Roaster and Trainer.

Techniques of the Specialty Barista
2 Sessions 21st and 28th of January, 5pm. Mecca Espresso, Ultimo.
Techniques of the Specialty Barista was designed to provide a comprehensive and practical-based overview of the most up-to-date coffee-making skills required for today’s specialty baristas. Participants are taught the skills they will need to hit the ground running as they enter the specialty coffee world.

The course is suitable for experienced baristas as well as novices keen to learn professional techniques  used at the forefront of the specialty coffee industry. Max 4 participants to ensure quality of learning. This course is delivered by Tuli Keidar.

Science of Flavour and the Critical Evaluation of Coffee
29th of January, 6pm. Mecca Espresso, Ultimo.
Being able to asses coffee accuratly and confidently is now a pre-requisite for any specialty barista. Without formal training, the process of becoming a good “taster” can take many years. This course is designed to provide a clear foundation and help lay the first building block. This course is delivered by Sam Sgambellone.

Understanding the principles of Extraction using Refractometers
5th of February, 6pm. Mecca Espresso, Ultimo.
This education session will seek to provide a base level understanding of the principles of the extraction process and better equip you to make informed decisions when you are deciding how best to represent a particular coffee.

The session will be limited to a small group to maximise interaction. We will begin by exploring the theory behind extraction, then we will move to brewing coffee and taking measurements using the Refractometer.

 

You can see the full event listing here, any question please email us.

Nordic Approach Cupping – Sydney

Nordic Approach is a forward thinking green coffee importer targeting the emerging market of quality roasters with a goal to take coffee quality to a new level,  starting at the source,  and bring these coffees to roasters that appreciate it’s value and uniqueness.

They not only raise the quality of the coffee but to contribute to a more transparent and sustainable coffee trade by developing close relationships and build bridges between farmers, exporters and roasters.

We are working with Morten Wennersgaard and Tim Wendelboe to help introduce their current offer list to Sydney’s roasters, as we have limited samples available we will be doing this through a cupping event on Thursday the 18th of October.

The focus of the event will be on Central Kenya, Western Ethiopia, El Salvador and Hondouras. If you would like to get an idea of the coffees that are available you can check their offer list here.

If you are a green coffee buyer and would like to come along and asses these coffees, or if you have any questions please contact sam@coffeekaizen.com