Announcement

Collapse
No announcement yet.

First roasts with data logger

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Re: First roasts with data logger

    Theres a lot of good advice here and I read these forums extensively before I roasted my first batch. As far as temperature goes, it is a variable because of the different DMMs, Bread Makers, probe depths and lengths. So a comparison is only of limited value.

    I started off with my temp probe deep in the mass but found that it didnt really reflect the actual 1C temp so I raised it up. Then I tried using a cover but I found that this only reduced the amount of heat needed to bring the mass up to temp and was something else I had to tinker with while roasting so I then went coverless again.

    With my first roast, I set the heat gun at 500C and finished with it at 320C. The first roast was just acceptable but a comedy of errors put it past rolling 2C (I put the corretto together while the missus was at lunch and tried to get away with a stealth roast before she got home. When the first crack of 2C arrived, I realised that I didnt have an oven mitt to pull the pan out with so I raced inside and tripped over the dog. By the time I got back to the garage, rolling 2C was ending and the beans were a tad dark).

    Now I start with the gun at around 300C, ramp it up to about 450C to give me a steady 10-11 degree increase and then drop it about 50 degrees to slow the ramp up to 2C. This gives me around 5 minutes between cracks and produces coffee to my preference.

    It seems that your coffee roasting journey evolves as time goes on and you will end up making small procedural changes along the way. The best advice is to make sure you can replicate the successful changes so that your roasting is consistant. When alls said and done, its what ends up in the cup that matters and one mans meat may be another mans poison.

    I have included the graph of my first roast (minus the accident with the dog) and latest roast just to give you an idea of how things have changed. The ramp that I use now is much more steady and it amazes me how much control you can get with a corretto set up.




    Comment


    • #32
      Re: First roasts with data logger

      I did a couple more roasts, the software makes it so easy to follow prior profiles.

      I cant find the file with the bean type, mass etc data that is input into the window.

      Here the latest roast I did (Tanzania Uru Estate):



      One more question: could you get a very light roast without hitting second crack? Once I hit second crack, the roasts tend to be dark-ish. Still taste great, just curious on the process for a lighter roast.

      Cheers

      Comment


      • #33
        Re: First roasts with data logger

        Gday "artman"...

        Probably not possible with most home-roaster designs but with the infinite control options available on decent commercial roasting machines, perhaps it can be done.

        Most CSers will pull and cool roast batches before 2nd-Crack starts, in order to achieve lighter roasts. Since you are using the CS Roast Monitor Software mate, you should be able to predict (by temperature) where in the profile the batch currently sits, between 1st and 2nd. Try some smallish batches dumped at different positions along the profile after 1st and then see how you like the results in the cup.

        Thats the beauty of the CS RM Software, puts you in a great position of control.... 8-)

        Mal.

        Comment


        • #34
          Re: First roasts with data logger

          Thanks Mal, all clear now. Good idea trying different end times, I have been taking some tasting notes of the roasts, but I think they are too broad, need to work on more detail if I will be comparing the same beans at different roast levels..

          Cheers

          Comment


          • #35
            Re: First roasts with data logger

            Its a lot to take in. It really does seem that a super detailed experimental log needs to be kept over a reasonable period to be able to make any sort of educated adjustments to be able to achieve a specific taste profile.

            DesigningByCoffee - I have been leaving my roasts on heat a little longer into second crack as you suggested and there are very noticeable chocolate flavours coming through which werent there before.

            Comment


            • #36
              Re: First roasts with data logger

              Originally posted by 6C65696B663C0A0 link=1318770716/34#34 date=1321875175
              Its a lot to take in. It really does seem that a super detailed experimental log needs to be kept over a reasonable period to be able to make any sort of educated adjustments to be able to achieve a specific taste profile. 
              Youre spot on Ross... 8-)

              The whole learning process can be made easier, by sticking with a single bean variety until such time as you know its idiosyncrasies inside and out. Once you have this level of knowledge and experience behind you, it isnt such a big deal transferring same to other bean varieties. Mind you, as with all fresh food, theres always those that prove to be the exception to the rule, but thats half the fun....

              Mal.

              Comment


              • #37
                Re: First roasts with data logger

                I just did my first roast with a data logger (why it took me so long, i dont know) in my Behmor and whilst the temperature reads were consistent, they were clearly far too low.

                I was using 250g on P2, Ilb, A (my usual profile) and hit first crack around 11.20, at which time the temperature was only 151c.
                I dumped it at 16 minutes, with a small 2C occurring a few seconds later.
                At dumping the temperature was 158c.

                Me and drills dont go work so im just using the bead thermocouple and so far ive not found a way to mount it so its just sort of hanging in there, which is probably why its not reading accurately.

                I thought of getting some high heat resistant tape to secure it to the side and then have it hooked around the left mount but so far i havent found a tape capable of holding up to such heat.

                Can anyone suggest a solution for a hopelessly inept handyman?

                EDIT: With the second roast i managed to somehow fit the bead TM a little more securely over the left mount and early on the temperature reads were seemingly far more accurate (about 130c after 5 minutes), however as the roast went on, the temperature seemed to revert back to the inaccurate readings of the first roast, basically peaking and stalling at 150c (at 1C), and even dropping further as 2C was about to hit.
                Very weird, but hopefully if i can find a solution to mounting the bead TC i might get more accurate and helpful results.

                Comment


                • #38
                  Re: First roasts with data logger

                  Sounds like you are not measuring the bean temp, and your temps are inconsistent. You need to have the temp sensing point in the bean mass and also it needs to be fixed in location, so your temps are repeatable from roast to roast.

                  Not sure how you could secure the probe in your roaster, maybe you can glue a small bracket and secure the probe to this? Would need to be sure the glue will not give off any toxins etc in the heat.

                  Cheers

                  Comment


                  • #39
                    Re: First roasts with data logger

                    Originally posted by 3625233A3639570 link=1318770716/37#37 date=1321924784
                    Sounds like you are not measuring the bean temp, and your temps are inconsistent.
                    I thought there wasnt actually a way of measuring true bean mass temp with the Behmor.

                    Ive seen both Andy and Mal reference being able to, and apparently successfully, simply sit the bead TC in the roaster which was my aim.
                    It obviously cannot be touching the drum, so i thought sitting right beside it, hooked over the left mount would be the most apt place for it.

                    Perhaps ive just totally misinterpreted something along the way.

                    Originally posted by 3625233A3639570 link=1318770716/37#37 date=1321924784
                    Not sure how you could secure the probe in your roaster, maybe you can glue a small bracket and secure the probe to this? Would need to be sure the glue will not give off any toxins etc in the heat.
                    Ah, interesting idea, although it still wouldnt allow me to truly measure bean mass temps.
                    I thought about using a high heat sealant to secure the bead TC to the roaster but even thats too advanced for my feeble handyman skills and i really dont want it to be totally permanent anyway.

                    Thanks for the suggestions.

                    Comment


                    • #40
                      Re: First roasts with data logger

                      Sorry, I am not sure of the design of your roaster, so cant help with intelligent ideas of mounting the probe. Have you tried a search? Maybe someone else has done this already?

                      Cheers

                      Comment


                      • #41
                        Re: First roasts with data logger

                        Originally posted by 293A3C252926480 link=1318770716/39#39 date=1321929483
                        Have you tried a search?
                        I certainly have, many times.

                        Originally posted by 293A3C252926480 link=1318770716/39#39 date=1321929483
                        Maybe someone else has done this already?
                        Ive heard of people somehow fixing the bead TC, hanging it over the left mount and getting accurate results but ive not actually seen an explanation of how theyve achieved it.


                        Comment


                        • #42
                          Re: First roasts with data logger

                          Originally posted by 030303490 link=1318770716/40#40 date=1321934670
                          Ive heard of people somehow fixing the bead TC, hanging it over the left mount and getting accurate results but ive not actually seen an explanation of how theyve achieved it.
                          Maybe find this post and try to PM the person, if they are still around they will probably get back to you.

                          Cheers

                          Comment


                          • #43
                            Re: First roasts with data logger

                            When I first used the Behmor I simply held the probe in place by using a large heavy gauge wire paper clip which held the thermocouple wire in place. The wire will move as it is not a rigid mount but it is OK as a starting point.The critical thing is to ensure the tip is nominally in the same place for every roast as any variation in position will change the relative temperatures being measured. Also make sure the probe tip is not touching any surface of the roaster and is simply measuring free air. I lined it up with the back edge of the drum. If you bend the wire gently where it goes through the door and seal you will find it lines up fairly well each time. Try to work on drilling the holes using the dimensions Andy has given and using the SS probe it is much easier. Neither method will give the exact bean temp but what you are aiming for is repeatable roasts, as long as probe is in the same place each time you are still repeating the same conditions. Good luck and I hope this is of assistance.





                            Comment


                            • #44
                              Re: First roasts with data logger

                              Originally posted by 6666662C0 link=1318770716/38#38 date=1321925573
                              Ive seen both Andy and  Mal reference being able to, and apparently successfully, simply sit the bead TC in the roaster which was my aim.
                              Andys diagram for the installation of the s/s probe is definitely the best solution.... Do you have any relos or friends who are adept with power tools, etc? Some freshly roasted coffee on offer can work wonders for enthusiasm.... :P

                              As an aside, have you checked the accuracy of the t/couple-meter combo? Quite easy to do - Boil some water in an open saucepan then immerse the probe below the surface while boiling. It should read 100deg.C or very close to it.... At least you will know, one way or the other, the status of your metering.

                              Mal.

                              Comment


                              • #45
                                Re: First roasts with data logger

                                Originally posted by 152A333A2C000D5F0 link=1318770716/42#42 date=1321942546
                                When I first used the Behmor I simply held the probe in place by using a large heavy gauge wire paper clip which held the thermocouple wire in place.
                                Thanks for the suggestion (and the incredibly helpful photos).
                                Seems an easy interim solution if i can find said paper clips.

                                Originally posted by 1B36323E335F0 link=1318770716/43#43 date=1321948733
                                Andys diagram for the installation of the s/s probe is definitely the best solution.... Do you have any relos or friends who are adept with power tools, etc? Some freshly roasted coffee on offer can work wonders for enthusiasm.... Wink Tongue
                                Probably not, sadly.
                                I might need some new friends.

                                Perhaps i need to get myself a drill and learn how to do such things.
                                Theres no wiring in the area Andy suggests for the drilling, is there? And the drilling itself is pretty basic and fool/Ristrom proof?
                                Originally posted by 1B36323E335F0 link=1318770716/43#43 date=1321948733
                                s an aside, have you checked the accuracy of the t/couple-meter combo? Quite easy to do - Boil some water in an open saucepan then immerse the probe below the surface while boiling. It should read 100deg.C or very close to it.... At least you will know, one way or the other, the status of your metering. Smiley
                                Thats a wonderful suggestion, Mal, thanks.
                                I did it this morning and found it pretty accurate, reaching 99 degrees at boiling point, so you probably cant expect much more than that.

                                Comment

                                Working...
                                X