Hello all,

Curious to know if anyone has these troubles from time to time as I do. I'll do a profile on a coffee I really like, then when I go back to and repeat that profile it doesn't taste the same. I'm not talking about minor variations, but drastic ones. It doesn't happen a lot, but when it does it's insanely frustrating. Anyone else experience this?


*should be noted: that I'm pretty certain it's not pore probe placement. I've gone to great lengths to find a good spot.

** it also should be mentioned that the weight loss lines up too(meaning the good and bad roast both have the same perntage weight loss.)

How much time has elapsed between roasts when you have this experience? One possibility is that the green coffee has aged, losing some of its vitality, between the initial roast and the subsequent attempt at replicating it.

I've had it happen to me with a fruit bowl Ethiopian DP. The wow! on it was so unstable that a month after a couple of 95 point roasts all I got was dust. It was the first time I understood why some pros are leery of DPs.

Green beans are far more sensitive to storage conditions than I ever thought. For instance, Dark Matter, a roaster in Chicago, occasionally sells roasts of greens they store in Heaven Hill bourbon barrels for three to six months. The coffee's flavor is so dominated by new oak that it tastes more like a bourbon cocktail than coffee (it's also really good if you're into oaked spirits). If the greens can pick up a flavor this easily; storage becomes a major issue.

[creative nickname] wrote:How much time has elapsed between roasts when you have this experience? One possibility is that the green coffee has aged, losing some of its vitality, between the initial roast and the subsequent attempt at replicating it.

Really short intervals, like one day to the next.

another_jim wrote:I've had it happen to me with a fruit bowl Ethiopian DP. The wow! on it was so unstable that a month after a couple of 95 point roasts all I got was dust. It was the first time I understood why some pros are leery of DPs.

Green beans are far more sensitive to storage conditions than I ever thought. For instance, Dark Matter, a roaster in Chicago, occasionally sells roasts of greens they store in Heaven Hill bourbon barrels for three to six months. The coffee's flavor is so dominated by new oak that it tastes more like a bourbon cocktail than coffee (it's also really good if you're into oaked spirits). If the greens can pick up a flavor this easily; storage becomes a major issue.

The current coffee that is doing this to me is an extremely expensive natural Ethiopian. But I store my green vac sealed in a freezer now, so Im hoping that age inst the case.

This has happened to me before on other really nice coffees as well. There was a washed Ethiopian last year that was one of the best coffees id ever had. I would repeat the profile time and time again, but the coffee never tasted the same.

SM's DP Ethiopia Konga has been doing this to me for the past month.

Though I'm on a Behmor, so honestly repeatability is a bit of the issue (though less so now with the 1600+ panel). That said, this DP Ethiopia is far and away the most finicky coffee I've ever roasted of my hundred or so batches. It performs differently in the roaster from batch to batch, and drinks differently in the cup from day to day.

Jeff

dustin360 wrote:Hello all,

Curious to know if anyone has these troubles from time to time as I do. I'll do a profile on a coffee I really like, then when I go back to and repeat that profile it doesn't taste the same.

Are you absolutely sure it's the roast and not the brew? I.e, you sure your cupping/brewing variables are absolutely consistent? I can't recall the last time I saw any variation within a season (and being in LA there hasn't been much seasonal variation the last 2 years hahaha) for a given bean.

• What are the intervals for the inconsistent roasts? In other words, which profile(s) are we talking about?
  
  When you say profiles are consistent does that include airflow as well as the BT temp progression?
  
  There's always some roast to roast variance, how close do you stay to your target intervals?
  
  What are your warm-up and successive batch Charge temp rituals?
  
  Do your Turning Points come at consistent times and temps?
  
  Got plots?

Rich

the_trystero wrote:Are you absolutely sure it's the roast and not the brew? I.e, you sure your cupping/brewing variables are absolutely consistent? I can't recall the last time I saw any variation within a season (and being in LA there hasn't been much seasonal variation the last 2 years hahaha) for a given bean.

Good call Greg. But thats something i looked at all ready. I own a refractometer, and I take readings on all of my good cups then record that info with the roast info in artisan. I record brew temp/time/grind setting/brew method/tds/ and extraction.

boar_d_laze wrote:

• What are the intervals for the inconsistent roasts? In other words, which profile(s) are we talking about?
  
  When you say profiles are consistent does that include airflow as well as the BT temp progression?
  
  There's always some roast to roast variance, how close do you stay to your target intervals?
  
  What are your warm-up and successive batch Charge temp rituals?
  
  Do your Turning Points come at consistent times and temps?
  
  Got plots?

Rich

This coffee the airflow doesnt change, same setting for the whole roast. Ive tried repeating this roast as my first batch of the day, and the last(so some warm up, and totally warmed up).

The image on top is the good roast, the one behind isnt. The blue line is bean temp, the black line below bean is a second probe I installed. I only use the second probe to tell me if something is off with the first. Red is inside the drum. The other black line sits outside the drum, but I really dont use that for much.

Does this really never happen to others?




*also the crack times seem off, but this coffee doesnt really crack. So im just estimating when I think crack should be.