[Mrboots2u]

Can you make your own distilled water with a pan on a stove and ice cubes or does it need to be prosessed in some other way?

A trip to B and Q is easier.

 

[Zephyp]

I'm from Norway, so I'm not so sure about that.

What am I looking for in a store? I see a lot of descriptions out there. Distilled, deionized, sterile, battery water etc.

 

[MWJB]

Distilled or deionised. Motor spares shop would have it.

Not perfumed stuff for laundry irons.

 

[Zephyp]

Do motor shops have it for filling batteries? I found "Battery Water" at Biltema, a big store that sells everything and car stuff.

The datasheet says demineralised with reverse osmosis. Maybe not the same as destilled or deionized?

Product description:Battery water is a demineralised quality water. All impurities and minerals are eliminated. Production method: Reverse Osmosis (RO)

Applications:

Batteries, steam-irons, humidors, water based cooling systems.

 

[MWJB]

That will be fine

 

[Zephyp]

Got my VST today! The motor shop only had demineralized water (desalted, ion switched or something), so I got that. The procedure was pretty straightforward and I got a reading of 1.38%. How long should I let the brew cool before measuring? I put it in a small cup while I zeroed the refractometer and it probably sat there a couple of minutes before I put it on the reader. I should think it cools down pretty fast when first drawn into the pipette, then poured into a small cup and then put into the refrac. I also put the demineralized water into a similar cup a minute before using it to zero.

Anyone with the VST Android app here that can explain how to use it? I've tried putting in values here and there, but when I change one value it changes other values, so I'm not quite sure how to input this. Or anyone with the VST app can input it to their app (or formula) and see that I get the same EY. I haven't changed anything in the app, like Co2 and moisture.

Here's the data from the brew:

Dose: 14.45g

Brew water: 240g

Beverage: 208.8g (I weighed the server before and after brewing)

TDS: 1.38%

Brew method: V60 01. Water off boil before wetting filter. Mark's 35g regime and 6 pours. 30g bloom with a stir.

Drawdown: 3:41

Coffee: Kenyan

Taste: Not quite where I want it to be, maybe too acidic (I say that about every brew that's not ideal). I'm terrible at telling sour and bitter apart. I did not get any tingling on the tongue as I sometimes do. Not sure if that is indication of one or the other.

 

[Mrboots2u]

Got my VST today! The motor shop only had demineralized water (desalted, ion switched or something), so I got that. The procedure was pretty straightforward and I got a reading of 1.38%. How long should I let the brew cool before measuring? I put it in a small cup while I zeroed the refractometer and it probably sat there a couple of minutes before I put it on the reader. I should think it cools down pretty fast when first drawn into the pipette, then poured into a small cup and then put into the refrac. I also put the demineralized water into a similar cup a minute before using it to zero.

Anyone with the VST Android app here that can explain how to use it? I've tried putting in values here and there, but when I change one value it changes other values, so I'm not quite sure how to input this. Or anyone with the VST app can input it to their app (or formula) and see that I get the same EY. I haven't changed anything in the app, like Co2 and moisture.

Here's the data from the brew:

Dose: 14.45g

Brew water: 240g

Beverage: 208.8g (I weighed the server before and after brewing)

TDS: 1.38%

Brew method: V60 01. Water off boil before wetting filter. Mark's 35g regime and 6 pours. 30g bloom with a stir.

Drawdown: 3:41

Coffee: Kenyan

Taste: Not quite where I want it to be, maybe too acidic (I say that about every brew that's not ideal). I'm terrible at telling sour and bitter apart. I did not get any tingling on the tongue as I sometimes do. Not sure if that is indication of one or the other.

20.81 % EY

Kenyan and acidic go hand in hand

How was it for strength ? You could go a little finer and try again.

 

[Mrboots2u]

Im on an old MacBook versions somewhere ther is probably a padlock icon that need to be unlocked for you to input .

 

[MWJB]

Put the DI water on the lens for 30s before zero'ing (press menu twice, "go" to set zero, then "go" to read the DI water - should give "0.00")

After transferring a sample to the cup to cool, leave 30s minimum.

After dropping cooled sample on the lens leave 30s minimum, then take few reads & average if they change.

I don't have any Apps but the Windows version works by setting the parameter you want to keep constant (for me that's dose to 3 digits) then you enter %TDS and use the slider/enter gm Bev & read off the %EY.

Try a little finer?

 

[Zephyp]

20.81 % EY

Kenyan and acidic go hand in hand

How was it for strength ? You could go a little finer and try again.

I definitely want the acidity, but it wasn't quite balanced. I think strength was fine, I've been using 1:16.6 for a long time.

Im on an old MacBook versions somewhere ther is probably a padlock icon that need to be unlocked for you to input .

Ah, yes, the padlock gave me more control. It does still change BW or BEV whenever I change the other. Should I just input BEV and leave BW be? Some water will of course evaporate during the brew, maybe that's where the difference is. If I try to input 240 BW, BEV automatically goes to 214 and when I input 209 BEV, BW automatically goes to 235.

When I put in 14.45, 208.8 and 1.38, I get 20.77 EY.

Put the DI water on the lens for 30s before zero'ing (press menu twice, "go" to set zero, then "go" to read the DI water - should give "0.00")

After transferring a sample to the cup to cool, leave 30s minimum.

After dropping cooled sample on the lens leave 30s minimum, then take few reads & average if they change.

I don't have any Apps but the Windows version works by setting the parameter you want to keep constant (for me that's dose to 3 digits) then you enter %TDS and use the slider/enter gm Bev & read off the %EY.

Try a little finer?

I didn't try to read the DI water, but I'll do that next time.

When you say take a few reads, you mean just leaving the sample on the prism and read it a few times in succession?

Yeah, I'll try a bit finer and see what happens.

 

[MWJB]

When I put in 14.45, 208.8 and 1.38, I get 20.77 EY.

When you say take a few reads, you mean just leaving the sample on the prism and read it a few times in succession?

Yeah, I'll try a bit finer and see what happens.

Sure, leave the same sample on the lens and press "go" 3 or 4 times.

20.77% & 20.81% are in effect the same reading. 0.04%EY isn't enough to indicate a difference.

 

[Zephyp]

1.41, 1.40, 1.40 and 1.40% on the next brew. The BEV however, I measured to 207 (down from 208.8), which lowered the calculated EY, ending up at 20.89%. Just slightly higher. Drawdown was just 7 seconds longer, so I didn't expect a huge change.

Well, I'm started and I'll record the brews in a log to see how it changes as I change the grind and pour regime. The DI test read 0.00. I've been using the same pipettes and clean them with DI water after use. It might still have some particles in there, but when you draw in and pour out the sample multiple times before taking the final sample, I have trouble imagining it making a big enough difference on the test. I don't mix the pipette for DI and brew though.

I see that Mark's getting good brews in a range from 18.5-22%, which is understandable since every bean is different. When I'm testing and tasting, what outer limits should I stay within? If I now wanted to increase the EY and see how it changed the brew, do I stop at 22% before I try going the other way, towards 20 and below? Of course, if the brew taste great at 22%, there's no need, but if I'm not happy, I assume I want to go the other way next time.

Anything else to keep in mind while experimenting on this?

 

[Mrboots2u]

1.41, 1.40, 1.40 and 1.40% on the next brew. The BEV however, I measured to 207 (down from 208.8), which lowered the calculated EY, ending up at 20.89%. Just slightly higher. Drawdown was just 7 seconds longer, so I didn't expect a huge change.

Well, I'm started and I'll record the brews in a log to see how it changes as I change the grind and pour regime. The DI test read 0.00. I've been using the same pipettes and clean them with DI water after use. It might still have some particles in there, but when you draw in and pour out the sample multiple times before taking the final sample, I have trouble imagining it making a big enough difference on the test. I don't mix the pipette for DI and brew though.

I see that Mark's getting good brews in a range from 18.5-22%, which is understandable since every bean is different. When I'm testing and tasting, what outer limits should I stay within? If I now wanted to increase the EY and see how it changed the brew, do I stop at 22% before I try going the other way, towards 20 and below? Of course, if the brew taste great at 22%, there's no need, but if I'm not happy, I assume I want to go the other way next time.

Firstly , how did those brews taste? to some degree the amount you can push EY will be down to the grinder and water as to if they are tasty and in the end only you an evaluate that. I enjoyed v60 brews 21% ey ish with the EK , bean dependent tbh.

In the end though its just a measure. My 21% brew with a hand grinder will be different to a 21% brew with a bulk grinder ( even if the pour and dose and bed weight and tds are the same ) . Try going finer again and taste .

 

[MWJB]

I see that Mark's getting good brews in a range from 18.5-22%, which is understandable since every bean is different. When I'm testing and tasting, what outer limits should I stay within? If I now wanted to increase the EY and see how it changed the brew, do I stop at 22% before I try going the other way, towards 20 and below? Of course, if the brew taste great at 22%, there's no need, but if I'm not happy, I assume I want to go the other way next time.

Anything else to keep in mind while experimenting on this?

20.77 to 20.89 is close enough to still regard as 'no change'.

For Kenyans I wouldn't aim to stay below a limiting number, they're usually very soluble and can be way over 20% at an under developed roast. I'd use Kenyans to establish the higher tolerance of your range, I find they taste good (to me) often 21%+, maybe even a tad over 22%.

I wouldn't try and establish a datum for Kenyans around what I would consider an average extraction for a range of coffees (for me, an average will be a little over 20% for at least 10 different coffees).

If you go

 

[Zephyp]

Firstly , how did those brews taste? to some degree the amount you can push EY will be down to the grinder and water as to if they are tasty and in the end only you an evaluate that. I enjoyed v60 brews 21% ey ish with the EK , bean dependent tbh.

In the end though its just a measure. My 21% brew with a hand grinder will be different to a 21% brew with a bulk grinder ( even if the pour and dose and bed weight and tds are the same ) . Try going finer again and taste .

The primary reason for getting the VST was because I find it really difficult to tell where to go based on taste. I know what good coffee taste like, but I'm not very good at putting the taste when I don't like it into words. The brews weren't terrible, but they weren't ideal. I want to say it was too acidic, but I've had brews where I thought it was too acidic and my girlfriend said it was too bitter. Who's "correct" I can't say, but generally she's got a better palate than me when it comes to coffee, wine and food. Maybe using the refractometer and tasting the difference of 18, 20 and 22% EY will improve my palate a bit.

I know it's just numbers, but I think it will make it easier to figure out where I'm at and where I want to go. I don't expect I could even use the EY from the roaster or coffee shop since they might have different wanter and a better grinder. My Comandante doesn't match the EK43.

I'll go even finer next time and see if I get readings closer to 22% and how that taste. I often see people talk about an 18-22% range, which I think is the SCAA recommended range too. Before tasting and testing, I can't know at which EY I will enjoy the coffee the most, so I'll just have to test, taste and record.

I normally just make one brew a day, but I see that I can easily end up making a lot more coffee with this gadget. At least initially when I'm figuring things out and dialling in brews.

 

[Zephyp]

20.77 to 20.89 is close enough to still regard as 'no change'.

For Kenyans I wouldn't aim to stay below a limiting number, they're usually very soluble and can be way over 20% at an under developed roast. I'd use Kenyans to establish the higher tolerance of your range, I find they taste good (to me) often 21%+, maybe even a tad over 22%.

I wouldn't try and establish a datum for Kenyans around what I would consider an average extraction for a range of coffees (for me, an average will be a little over 20% for at least 10 different coffees).

If you go

If you go from a Kenyan til a Braizilian, do you just use your brew experience to change your pour regime?

Ideally, I want to find a grind where I can just change the pour regime to manipulate EY across the range of coffee I buy. I'm usually drinking Africans, mostly because I often find the South-Americans to taste too much like "regular coffee" and not finding the notes on those. I hope I'll be better able to find them when working with the VST. I've had some amazing Brazilians, but usually when I buy something from there, I'm not too happy with it. Based on my experience, I've imagined it being because those notes don't stand out as much as Africans, and are tougher to find if the brew isn't balanced.

Just changing grind is fine for now. It's an easy way to change EY and taste. Once I've gotten some work in, I can try to settle on a grind and work on pour regime.

 

[MWJB]

If you go from a Kenyan til a Braizilian, do you just use your brew experience to change your pour regime?

Just changing grind is fine for now. It's an easy way to change EY and taste. Once I've gotten some work in, I can try to settle on a grind and work on pour regime.

I generally don't change anything once grinder & brewer are dialled in for similar roast levels (when I say similar, I mean filter roasts from speciality roasters, if I were to brew some supermarket beans I'd need to change).

I can if I want to, of course, and there can be more wrong with a roast than the EY you are getting, but having some coffees fall 18-20% and others fall 20-22% (>95% falling 18-22% overall) seems to work out pretty well for me. I expect them to be different & enjoy the difference, I don't try and brew them differently to make them all extract the same, that sounds like a chore & a hiding to nothing

At some point the experimenting has to give way to relaxing & enjoying the scenery.

 

[Zephyp]

I generally don't change anything once grinder & brewer are dialled in for similar roast levels (when I say similar, I mean filter roasts from speciality roasters, if I were to brew some supermarket beans I'd need to change).

I can if I want to, of course, and there can be more wrong with a roast than the EY you are getting, but having some coffees fall 18-20% and others fall 20-22% (>95% falling 18-22% overall) seems to work out pretty well for me. I expect them to be different & enjoy the difference, I don't try and brew them differently to make them all extract the same, that sounds like a chore & a hiding to nothing

At some point the experimenting has to give way to relaxing & enjoying the scenery.

The less I have to adjust, the better. It wouldn't be to make everything taste the same, but rather bring out the flavors of the individual beans. A balanced brew where the one from Honduras taste like chocolate and the African like citrus. I don't think I could ever make one taste like the other and still be good tasting.

 

[Zephyp]

Today I made a brew which gave readings of: 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.41, 1.41. Could the change from first to last reading be change in the temperature of the sample? I gave it at least 1 minute in a cup and another minute on the VST before running it, but coming straight from the server it was perhaps it was still too hot.

I tightened the grind on the Comandante with 3 clicks, drawdown was 3:50. Assuming I performed the test correctly, could a lack of measurable and tastewise difference be attributed to technique? I was expecting a bigger difference in taste and TDS with 3 clicks finer. I though the brew had some difference to yesterday, but not significantly.

My experimentation with brewing using an AP or something similar to distribute the water over the V60 and not disturb the bed as much was encouraged by a search for better consistency. I've seen it before too, that I can end up with pretty different drawdown times and taste in the cup using the same recipe. Maybe I'm not careful enough with my technique.

Of course, one sample is far from enough to make conclusions, but every brew is a bit of experience. I might intentionally want to brew to the limits of EY just to see how it taste and if my palate can make sense of it. I find it easier finding a middle spot if I know the outliers.

I will find some articles and read up on grind size, its relation to TDS and taste. I got some holes in my understanding of coffee brewing and it would be interesting to fill some of them. I've got some material on this forum, the Barista Hustle articles and some other stuff.

I've so far been doing the testing right after brewing and since it doesn't take more than a few minutes, I still got a hot brew to enjoy. If I at some point wanted to delay the testing several hours, would the sample still be useable? Maybe I'd need a small container I can put a lid on to prevent water from evaporating? If I made two brews one day and put the first sample in a container, let it sit in a cupboard 4-5 hours, made the second brew later, also putting it in a container, then testing both samples after I was done drinking the second brew, would those tests be reliable? Maybe shake the container a bit first to swirl around any particles that might have settled on the bottom.

 

[MWJB]

I've never seen that large a swing in readings, so yes, I suspect temp may have been too high on the 1st readings.

You gave us the TDS but not the EY?

I don't know how much change 3 clicks makes on a Commendante, how many to a full turn.

I still find results for V60 better with a kettle, good with a AP but more faff. For the Kalita Wave I think the AP screen works better with the shallower flat bed.

For the same coffee, same weights, same grind, I'd expect you to be able to keep 10 brews within a %, or a std dev in EY of less than 0.5%EY.

So, making maybe very small changes in grind & natural deviation in EY is giving too high a noise floor for you to see a significant difference?

Push the issue, try a quarter turn on the grinder?