# Brew recipe consistency



## MWJB (Feb 28, 2012)

In trying out a few methods I have been logging brews & for each method/brewer I have been doing 10 brews changing nothing but the coffee (generally sticking to my typical preferences of light & medium roasts, from a selection of roasters) - brew recipe, grind setting & brew ratio are kept constant for each of these 10 brews. Each brew is the first & only brew for that method, with that coffee, so there's no subconscious steering of the brew to make it fit expectations.

What I'm finding is that overall the standard deviation is ~1%EY, averaged over 7 sets of 10 brews so far. For the more consistent recipes (averaged Sdevs over 6 groups of 10) it's 0.85%EY. For 55 brews so far, spanning 4 drip brewers, only 2 brews have fallen outside 18-22%EY. It suggests 95/100 brews will fall in the desired range, without adjusting grind setting.

So what's the value of this? Well, it tells me how consistent I am with certain methods & highlights methods where I obviously need to take more care & thought. It also gives me a pretty good datum/start point for that method. Interestingly for me, it has shown that there is no reason why French press brews should be any more consistent than percolation brews, which struck me as little counter-intuitive.

I reckon you could do much the same with taste assessment only, if you were careful & consistent with the other parameters. E.g. if you had a significant number of brews falling around/below 'like a little/don't know if I like it or not', maybe it's time to think about changing your start point for grind, pour method, or brew time.

For example, I think I need to be grinding my French presses finer than I already have been, also steeping longer & I can see no benefit in rinsing & preheating white Filtropa 1x2 papers in Melitta style brewers (if of the appropriate size).


----------



## MWJB (Feb 28, 2012)

A practical rule of thumb, without going through the statistics, might be to aim for a span of 3%EY for 10 identical brews, different coffee for each. Your mean EY in the region of 1.5%EY lower than your upper limit, E.g. if 22% is your upper limit, ~20.5% would be a good mean EY to aim for.


----------



## Nod (Sep 7, 2013)

Sounds an useful process and interesting the consistency is good..

What we really need is a little video of you making each brew method and recipe and then we can all copy....!!


----------



## MWJB (Feb 28, 2012)

Nod said:


> Sounds an useful process and interesting the consistency is good..
> 
> What we really need is a little video of you making each brew method and recipe and then we can all copy....!!


Ha ha, yes a video of each, should keep me busy until I'm 65. The 70 minute Sowden steep should be a real blockbuster 

The problem with videos is, almost as soon as you have finished it, you realise a better way of doing things & the video is now obsolete. I don't think people absorb the relevant information from videos well either, almost all drip brew videos I have seen are incomplete, or fail to explain why things are being done a certain way. Many are just bizarre. It's not like there aren't enough brew videos out there & those that are out there have addressed people's problems.

Here's a French press video, it took me about 2 days to make & edit...and it's not quite how I do it anymore...






Updates are:

1) Don't wait 1 minute from boil, pour the boiling water into the press. Ideally, weigh out the brew water into the kettle prior to boiling & pour as quickly as you can - once you have determined the losses on boiling your brew water weight in the press will be +/- a couple of grams. This should reduce the need for any stirring & give you a decent starting temperature. Avoid the dribbly pour business.

b) Don't stick religiously to a time, wait until the coffee has dropped to 55-60c in the pot, then pour carefully into preheated cups.

A 1 mug/200ml beverage, Kalita 185/Melitta 102 drip brew video is in the pipeline.

Back to the gist of the thread, it should be applicable to just about any brew method/recipe, it's just a case of logging those first 10 brews, each with a new coffee, and assessing where you are in regards to a good start point/datum, especially with respect to grind. If you have a very wide variance, it's likely something you are doing that is inconsistent, as opposed to the brewer itself, or grind.


----------

