Results 1 to 15 of 15
Like Tree39Likes
  • 9 Post By flynnaus
  • 5 Post By coffeechris
  • 6 Post By DesigningByCoffee
  • 4 Post By DesigningByCoffee
  • 5 Post By Yelta
  • 6 Post By deegee
  • 4 Post By Dimal

Thread: The problem with blends

  1. #1
    Member
    Join Date
    Oct 2012
    Posts
    50

    The problem with blends

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    I have a real issue with blends and this may not be a popular view...

    if we pre-roast blend then the beans in the roast each react differently to the heat, resulting in some over/under extracted beans.

    Then when the blend is extracted the beans will extract at different rates giving an uneven espresso.

    Fundamentally I can’t see How these issues can be overcome. Sensory lab have developed a blend of beans that extract st the same rates but that’s really the only way.

  2. #2
    Senior Member woodhouse's Avatar
    Join Date
    Dec 2016
    Posts
    326
    I was under the impression that post-roast blending was already the way to go.

  3. #3
    Senior Member flynnaus's Avatar
    Join Date
    May 2008
    Location
    Sydney
    Posts
    4,117
    Quote Originally Posted by Budgiesmuggler View Post
    I have a real issue with blends and this may not be a popular view...

    if we pre-roast blend then the beans in the roast each react differently to the heat, resulting in some over/under extracted beans.

    Then when the blend is extracted the beans will extract at different rates giving an uneven espresso.

    Fundamentally I canít see How these issues can be overcome. Sensory lab have developed a blend of beans that extract st the same rates but thatís really the only way.
    I think you are over thinking it. The proof is in the cup and the main objective is for the coffee to taste good. Variations in extraction rates doesnt mean the coffee will not be good. If a blend tastes 'uneven' then the idea is to change the proportions but not all beans will blend well together.

  4. #4
    Senior Member coffeechris's Avatar
    Join Date
    Jul 2011
    Location
    Melbourne
    Posts
    743
    I do a little of both and yes having a understanding of what beans roast well together helps. As Fynn mentioned above, dont over think it, have you thought of it in a way that if you didn't roast a bean with other ones it may not get the result it did had you roasted it on its own..

    Horses for courses...

  5. #5
    Life-long Learner DesigningByCoffee's Avatar
    Join Date
    Aug 2008
    Location
    Millthorpe NSW
    Posts
    2,040
    I often do a "Baggin's Blend" roast (all the beans that reside in Bag Ends!) from all sorts of stuff, and they never turn out badly – just chuck em all in pre-roast and charge ahead using a basic profile. While you will certainly get bean origins roasted in a way that is darker or lighter than you may roast them as a single origin, this can add some extra zing or some earthy chocolate that may just make the result come alive. As mentioned above - let taste be your guide!

  6. #6
    Junior Member
    Join Date
    Aug 2018
    Location
    Israel
    Posts
    23
    Quote Originally Posted by Budgiesmuggler View Post
    Sensory lab have developed a blend of beans that extract st the same rates but that’s really the only way.
    I don't think you need a lab to get to similar roast level of multiple types of beans in a single roast. You just need to first roast them separately, then match the beans that ended with similar roast times into a single blend and leave out the ones the require significantly more or less time.

  7. #7
    Junior Member
    Join Date
    Feb 2013
    Location
    Hobart, TAS
    Posts
    9
    Quote Originally Posted by Budgiesmuggler View Post
    I have a real issue with blends and this may not be a popular view...

    if we pre-roast blend then the beans in the roast each react differently to the heat, resulting in some over/under extracted beans.

    Then when the blend is extracted the beans will extract at different rates giving an uneven espresso.

    Fundamentally I can’t see How these issues can be overcome. Sensory lab have developed a blend of beans that extract st the same rates but that’s really the only way.
    Huh - this is quite interesting.. Some of my professional work is into material science and chemical digestion. Even the differing oil contents of the different beans would play a role (if everything were roasted together and to the same degree)

  8. #8
    Junior Member
    Join Date
    Aug 2013
    Posts
    9
    I definitely think that post blending is the way to go as the variation is too great in roasts. Agree with the comment above that the proof is in the cup and varied roast won't necessarily lead to uneven extraction.

  9. #9
    Life-long Learner DesigningByCoffee's Avatar
    Join Date
    Aug 2008
    Location
    Millthorpe NSW
    Posts
    2,040
    Quote Originally Posted by zcoffee View Post
    Agree with the comment above that the proof is in the cup and varied roast won't necessarily lead to uneven extraction.
    … or that the resulting combination of lighter/heavier under/over roasted beans won't knock your socks off with how good it tastes!
    Again, the battle of science and senses. Some pre-blend roasts work for this reason - while others don't. Just like roasting SO's to taste
    Andy, Dimal, greenman and 1 others like this.

  10. #10
    Junior Member
    Join Date
    Sep 2015
    Posts
    5
    The post blending is the only way to go!

    Different types of beans have various sizes, density and content of oils and hence they reach the "first crack" at different times in the process.

    Unless you carefully select the beans for your blend which are similar in size, density, oil contents etc, you almost inevitably need to consider post blending. 👍

  11. #11
    Senior Member Yelta's Avatar
    Join Date
    Jun 2009
    Location
    Moonta SA.
    Posts
    6,949
    I've played with both pre and post roast blending, have had good results both ways, some better than others, as you would expect.

    Don't think there's a right or wrong way, it's very much a case of personal preference.

  12. #12
    Senior Member deegee's Avatar
    Join Date
    Sep 2012
    Location
    Brisbane Southside
    Posts
    349
    Not trying to be contentious here, but for the sake of anyone relatively new to roasting who might read this - I have to put my two cents worth in here.

    " The post blending is the only way to go! " - - - - NO, it's not.

    " Different types of beans have various sizes, density and content of oils and hence they reach the "first crack" at different times in the process." - - - True - but that doesn't always matter.

    " Unless you carefully select the beans for your blend which are similar in size, density, oil contents etc, you almost inevitably need to consider post blending." - - - - Not so, as DBC said above bag end blends quite often work quite well, sometimes very well indeed.

    So this morning just for shots & giggles, I threw together equal amounts of all six beans in my stash. They were an Indian, a Colombian, a PNG, a Guatemalan, a Monsooned, and an Ethiopian sun dried (tiny beans).

    After 15 minutes in the Frankenpopper, with a fairly standard profile, the results were slightly mottled but no more than some recent SO roasts I've done.
    FC was a little longer than a typical SO, but there was a definite gap before the first snaps of second crack which was when I stopped, and cooled.
    Sampled this afternoon, as a "shortish" black, it was surprisingly good for a batch only a few hours post-roast. Not to mention the lack of care in selecting the beans.

    For the record - I probably post blend more than pre-blend, but both methods work equally well for me.
    It depends more on how well the beans go together, than whether they were mixed pre or post .
    Of course the other major factor is that I have to roast them well, and not stuff it up !!.

  13. #13
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,993
    Quote Originally Posted by Yelta View Post
    Don't think there's a right or wrong way, it's very much a case of personal preference.
    And, one's particular setup...
    For example, the smallest batch size I can roast in our setup is 350-400g and when that is considered against a 3-4 bean blend with a total batch size, for us these days, of 750g you can appreciate that post-roast blending just won't work. We have an el-cheapo popper that is capable of roasting maximum batches of ~80g, which works out fine for small Robusta additions to a blend but useless for anything else...

    Mal.
    greenman, Yelta, DaveD and 1 others like this.

  14. #14
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,993
    Well said DeeGee...

    Mal.

  15. #15
    Senior Member Yelta's Avatar
    Join Date
    Jun 2009
    Location
    Moonta SA.
    Posts
    6,949
    I'd agree with DeeGee.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •