The first thing that came to mind is roast. The problems started when you began home roasting with a Behmor. Now I'm not trying to knock the Behmor but there is commentary out there about how it can roast to a false color as compared to the inner bean, thus producing that sour effect. I've been home roasting for over 3yrs and get good results using a HotTop. I started with an iRoast and iRoast2 but didn't have much luck with either of those and quickly changed to the HotTop.
And so, if I was you I would go back to a state of last known good... Purchase a couple of reliable sources of quality freshly roasted beans and pull some shots with your Brewtus setup as per normal and see what you get. As for your water temp, when I last tested water drop temp into a vessel I noted a large drop in temp also. So, nothing may be going wrong and before walking too far down that path my recommendation is to get some good beans. FWIW. ---------------------------------------------------------------------------- -- Shaun Taylor http://shaundoreenevankeegan.blogspot.com/ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of cgfan Sent: 05 February 2009 02:07 To: Brewtus Subject: Re: Brew Temp problem on BII It seems that I may be having a similar issue with my Brewtus (I). My Brewtus has performed absolutely flawlessly for many years, giving me nothing but solid performance and incredible ristrettos shot after shot after shot. However I've also been battling an issue that just recently cropped up regarding sourness in the cup. Since the sourness seemed to have coincided with me starting to home roast again after a 2 months hiatus and still trying to get acquainted with a new Behmor roaster, I at first thought it was my roast. The roasts had somehow been tasting as if they were roasted lighter than the bean color would otherwise indicate. This was across several roast batches and beans, all properly aged post-roast. I then began to suspect temperature, so I started to raise the delta from it's normal setpoint of -8 all the way to a -11. It seemed to improve a bit, but not by much. It alarmed me that a 3 degree increase, which I already thought was a lot, hadn't yet solved the issue. Now I've always operated the Brewtus brew temps by taste. I never really thermally probed the Brewtus to determine where I should set the offset. I've always been able to hit a sweet spot in temps by at most a 2 degree tweak, but most often by only a 1 degree change up or down. However since changing it by 3 degrees did not dial it in, I decided for the first time to take some objective measurements, at least to the extent possible w/o a specialized setup. So I probed the brew water temps by running water through a naked grouphead (no portafilter to absorb any heat) straight into a (pre- heated) and thin borosilicate glass vessel. Probing the water in the vessel I realized that in spite of the -11 degrees of offset, it was still another 7 degrees C off at best the target temp of 96, or at worst up to 10 degrees C off. These findings were done on both a thermocouple and a very precise kitchen probe thermometer. I actually did try subsequently to raise the offset to -18, but did not get a proportionate increase. (Not that I suspect a -18 degree offset between brew boiler and grouphead, though I have no direct evidence of that either. If only I could make an independent measure of the brew boiler temps!) (I suspect that at some point the internal software in the temp controller must limit the actual boiler temperature setpoint to some numerical maximum regardless of the panel settings [boiler_temp_setpoint = panel_temp - offset_temp]. That is probably why I did not get a proportionate increase in temperature after reprogramming the offset.) So far I haven't opened up the skins, though I'm close to doing that. It's only recently that I've started to suspect the Brewtus and not my roasting, and now I'm sure that the problem lies somewhere inside the Brewt. So I suspect we may be seeing similar issues. Will post again if anything new comes up. In the meantime I'm open to any ideas or suggestions as to what may be going wrong. (In addition to the above possibilities, I wonder if another "failure mode" could be some kind of single-point blockage in the thermosiphon, thereby increasing the actual delta. I tend to rather think it's more an issue of the brew boiler not getting up to temp, but it's just a thought...) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Brewtus" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/brewtus?hl=en -~----------~----~----~----~------~----~------~--~---
