# Dialing in: the impact of degassing(?)



## MikeHag (Mar 13, 2011)

Beans: hasbean kenya karatina roasted 15 Aug.

Recipe: 29g. 440g brew water. Clever dripper. 2m40s steep then drawdown. Total time approx 3m30s.

Brew 1. Grinder setting 2.1. Result: 1.58TDS. Delicious. Chewy.

Brew 2: Ground coarser, 2.2. Result: 1.50TDS. Delicious. Clean.

THEN A FEW DAYS WAIT BEFORE...

Brew 3: Ground significantly coarser, 2.4. Less agitation too. Result: 1.72TDS(!) Tasted too strong, leathery.

All other parameters the same.

Conclusion: Beans have degassed a lot since brews 1&2 hence water can diffuse solids from the grinds more effectively. So to me there is no such thing as a filter grind, a chemex grind, a cafetiere grind etc, even within the context of the same beans. Dialing in every day is just as important as with espresso.

Any thoughts?


----------



## jimbow (Oct 13, 2011)

Wow! I usually find the reverse to be true in that I usually need to increase the dose or grind finer as the beans age. This has been based upon experiences with espresso though...

I completely agree about grinds for brewing methods and in fact I often find the descriptors (fine drip, chemex, french press, etc.) very misleading as the actual grind required is dependent upon the beans, dose, water chemistry, technique and, as you have demonstrated here, the bean's age.


----------



## garydyke1 (Mar 9, 2011)

I'm struggling with that very coffee on v60. It's not a regular occurance I open the bag with 3 days of roasting. Hence my normal grinding start point range isn't giving satisfying results . The bloom isn't behaving the same way as 7 or 8 days past roast . Needing to grind a touch finer to get any sweetness or aroma


----------



## MikeHag (Mar 13, 2011)

I've certainly been guilty of trying to 'defeat' the gas by adjusting grind. It's a battle that I now think is very difficult to win. Over the past weeks I've really gone off using beans within the first two weeks post-roast based on the improved results I get from waiting longer.

Absolutely amazed with today's results tho. I mean, brew 2 was on day 18 (post roast) and brew 3 was day 21. I'd have expected very little change in that 3 day period, and the bag was resealed too. I'm even starting to doubt myself as I write this! I'll have another go tomorrow to double-check!!


----------



## MWJB (Feb 28, 2012)

"Dialing in every day is just as important as with espresso." Amen.

Though, with the Clever Dripper & I guess with French press, if your grinder lacks fine adjustment, you can vary steep time accordingly. I think that with pour overs (& bearing in mind the draw down aspect of the Clever Dripper dovetails with this to some degree) there are really quite a lot of parallels with espresso...just over longer brew time & more water per g of coffee...but the resistance that the grinds present to the water is just as critical.

I've even given up making a note of how many clicks on my Porlex (I used to keep a chart...I love charts)...there are only really 3 states of grind, too coarse, in the ball-park, too fine ;-) The beans decide.


----------



## garydyke1 (Mar 9, 2011)

MikeHag said:


> So to me there is no such thing as a filter grind, a chemex grind, a cafetiere grind etc, even within the context of the same beans.
> 
> Any thoughts?


I would say for a fixed workflow (brew time, water temperature, recipe etc) there is a 'grinding range' for each of those brew methods (and you might want to start bang in the middle of that method's range for the first attempt) . You wouldnt ever swing from coarse-filter to espresso settings to allow for de-gasing/stale process in Chemex, for example.


----------



## MWJB (Feb 28, 2012)

GaryDyke wrote: "I would say for a fixed workflow (brew time, water temperature, recipe etc) there is a 'grinding range' for each of those brew methods"

For sure, as you eliminate variables in recipe & technique, the ball-park band for a working grind narrows...but there still may be room for those grinds (as typically attributed to brew methods) to dovetail as beans age/change....and certainly with respect to differing techniques & brewers within a common broad design (e.g. if using a jug with a more aggressive pour for a filter brew, you might try grinding finer than if using a pouring kettle with a more gentle action?)...though, I'm getting a little off the specific topic here?

I took Mike's statement to read that the specific device doesn't necessarily dictate the grind, as much as the bean type/age etc? Which makes sense to me...I guess I tend to look at the brewers as just "tools", with some flexibility according to technique. Though, obviously we would mostly aim to make techniques as consistent as possible in our own environments. But, caught on the hop, it's perfectly possible to make decent brews in a French press with a filter grind, this morning I made a 600ml brew in a cheap plastic pour-over, added water with a jug...grind was typically in the espresso range & I'm struggling to find anything "wrong" with the coffee (a fairly uncommon situation for me). 

Getting back to very recently roasted beans, does anyone elso notice, what I would call, a "slick" mouthfeel...not quite slimy, but a coating mouthfeel that doesn't seem quite so obvious/prominent as beans age?


----------



## garydyke1 (Mar 9, 2011)

When you only have 250g to play with , I think its useful to have a V60/CCD/AeroP = ''Start here'' setting, if only for sanity. From there the adjustment can be made as approriate. For me this start point is the median of a sensible range, and one that can be communicated with other coffee lovers using the same grinder, to compare experiences and results.

I just think we all want validation we are brewing nice coffee to the best of our abilities.

''Heres some coffee which i'm telling you is brilliant , go play with it'' isnt a useful as ''Try this coffee as V60 , maybe setting 18 on the Maestro/ 6 clicks from lock-up on the Porlex to get a decent extraction ''.

Enough is enough, Glenn - I want to hire your Mojo!


----------



## MikeHag (Mar 13, 2011)

I agree with the notion of having a starting point (perhaps at the centre of a range, or in my case based on previous brew logs) for a brew device, if always using a similar dose weight. Was just making an observation that sometimes people express frustration and confusion when a particular brew tastes poor even though they used the same grind as usual for (eg) the chemex, so I wanted to add another possible reason. I think the grind deltas can swing surprisingly far across different beans and different ages of beans.


----------



## jimbow (Oct 13, 2011)

I think we can probably have a "start here" grind range for particular brew methods but I wonder whether that range would still be specific to a given person's technique. I wonder if we all used the same brewer, starting with the same quantity of grounds from the same grinder at the same setting, would we achieve the same result? I notice especially with Chemex, I need a different grind depending upon the pouring technique I use.

We then have the age of the beans and environmental factors such as humidity to take into account too.

It would be really great to be able to communicate grinds effectively but perhaps the resulting TDS is a more concrete, transferable measurement that people can use to work back to a grind setting that works for their brewer and technique.


----------



## MWJB (Feb 28, 2012)

Jimbow wrote: "I wonder if we all used the same brewer, starting with the same quantity of grounds from the same grinder at the same setting, would we achieve the same result? I notice especially with Chemex, I need a different grind depending upon the pouring technique I use." Good question, we can only really speculate as to the results...so speculate I will, because I can't really help my self....

My theory would be, if we used the same beans, same amount of days since roast, same dose & starting brew ratio, same starting temp & say we all got all the water in the cone at 2min, brew ends at 3:30, giving the same weight of beverage...we would probably end up with reasonably similar extractions (with respect to TDS/yield...perhaps not so much flavour profile) irrespective of grind & pouring technique (within reason, you might use a kettle or a jug)...or perhaps, of ball-park consistency, given the amount of variation that we might find within our own techniques. My guess would be that a specific technique is less critical than having a repeatable technique and sticking to it (specifically with respect to time & output weight) & adjusting grind to accomodate?

The trouble with TDS is that it, by itself, does not indicate a bad extraction, or malfunction. It just indicates strength...without balancing against final brew weight or Ext Yield it doesn't tell you much - as Vince Fidele said in the video Mike recently posted from the NBC, "strength is a personal thing, if you have strong coffee you just drink less of it" (I'm paraphrasing, but that was th gist). Mike's 1.72TDS must have correlated to an extraction yield on the edge of, or beyond the typical ideal range (>22%)?

A picture paints a thousand words, so a video must be better....? ;-)






Note Tom Owen's comments about the stonking 10% brew ratio used in one of the brews & the slow pulse pour on the Hario...


----------



## jimbow (Oct 13, 2011)

Ah, see your point. I did not really mean for TDS to be used in isolation but rather in conjunction with other recipe details like beverage mass, dry mass, etc. I was trying to illustrate the difficulty in communicating specific grinds and that different grinds may be required by different people and different environments.


----------



## MikeHag (Mar 13, 2011)

I think TDS can be a good way to reference extraction, not just strength. Granted it only measures strength, but these days we tend to use brew ratios that mean if your TDS is too high or too low then your ext% will be too. Yup, my ext% were >22% for the first two brews and off the scale for brew 3. (I didn't reference the ext% for that reason... you'd have already known it was very high. )


----------



## Outlaw333 (Dec 13, 2011)

Something I found very interesting the other day was when I set the Lido on a guess for a new bag of Jirmiwachu, 44g for a 750ml Chemex, I was chatting to my brother at the time and ended up leaving the bloom period for 2mins 15, I did everything else as per usual and the result was EPIC! So thinking happy days I have found the sweet spot grind wise, about an hour later I made an identical brew save the bloom which was 55sec, the result was horribly under extracted.

So the question raised for me is, what exactly about the extended bloom rendered the coffee so much more yielding? Was it the release of more gas, was it maybe the coffee being allowed to swell and leaving its goodies more readily available, or maybe something else??


----------



## MWJB (Feb 28, 2012)

My guess would be that the extended bloom, rather than just being a gassing off phase, actually became part of the brew proper...possibly due to the small amount of water was less efficient, when you added a larger amount of water (more heat & solvent), you had a head start in getting to the sweeter part of the extraction?

Now you're going to have to A/B test the "happy accident", coarser grind, against the formal technique at a finer grind and see which is preferable! ;-) Never underestimate the benefits of a happy accident...

What is your typical grind range on the Lido with Chemex & pouring kettle?


----------



## jimbow (Oct 13, 2011)

It could also be that more of the coffee is wetted before the brewing proper takes place leading to a more even extraction. You might be able to achieve similar by stirring the bloom to make sure all the grounds are wetted. Grounds that are not wetted during the bloom can become hydrophobic later during the brew leading to an uneven extraction.


----------



## MikeHag (Mar 13, 2011)

I think the longer pre-wet will probably dissolve more of the gas, enabling more effective diffusion.


----------

