headmaster Posted September 3, 2015 Author Share Posted September 3, 2015 I hear you Phil! I suspected as much. By the way, I think you may be slightly out with the 102°c for the 1040, from my calcs it's closer to 100.2°c. Then if you add about 80m elevation above sea level, where I live, that takes off almost 0.3°, more than the sugar in the wort adds, so in theory, my boil should be at about 99.9, which is close to what my trusty Elitech STC1000 says during the boil, of 99.7 to 99.8.. I'm not a scientist however. You be the judge! Link to comment Share on other sites More sharing options...
Otto Von Blotto Posted September 3, 2015 Share Posted September 3, 2015 Mine boils about 99.8, sometimes it just hits 100.0C but never goes over it. That's measured with a Hanna digital probe thermometer. Regardless, I couldn't really care less as long as the thing boils. Link to comment Share on other sites More sharing options...
headmaster Posted September 3, 2015 Author Share Posted September 3, 2015 I guess it's a good check for your thermometer, to see if it's calibrated, at least for high temps, to know something about where it should be. Barometric pressure has an effect as well. Altitude correction for boiling temp calc: http://www.csgnetwork.com/h2oboilcalc.html Page that discusses boiling point of wort, includes example of 1040 wort: http://beerandwinejournal.com/boil-theory/ Example So let’s say we had 3.00 kg (6.6 lbs.) of pure maltose, and we dissolved it in 19.0 L (which weighs 19.0 kg) of pure water. We’d end up with a solution a little greater than 19 L (5.0 gallons), with a specific gravity around 1.060. What temperature would this wort-like solution boil at? ?T = 1*0.512 (°C kg mol-1)*[3.00 (kg)/0.342 (kg mol-1)]/19.0 kg = 0.236 °C ?T = 1*0.512 (°C kg mol-1)*0.462 (mol kg-1) = 0.236 °C So the temperature changed by +0.236 °C, giving us a boiling temperature of 100.24 °C (or about 212.5 °F). Not a huge change, but certainly within the precision of most thermometers to measure. Actual wort, of course, contains more than just maltose including some minerals with higher van’t Hoff factors. However, at a homebrew scale, these are added in gram quantities, so we would predict that their contribution to boiling point elevation would be much less than the sugars. In addition, atmospheric pressure also modifies the boiling point of a solution, as people who live at high elevations (and correspondingly lowered atmospheric pressures) can attest. Link to comment Share on other sites More sharing options...
antiphile Posted September 5, 2015 Share Posted September 5, 2015 By the way' date=' I think you may be slightly out with the 102°c for the 1040, from my calcs it's closer to 100.2°c.[/quote'] I haven't missed this one, BTW, Chippie. I just recalculated it, and I still get about 102C. This is also borne out by my temp readings (after thorough stirring and taking temp recordings from the onset of the hot break forming up to and including boiling point). Please forgive me and give me a bit of time to definitively respond as I've been driving for a bit over 36 hours out of the last 48 (left Brissie at 12:30 am on Thurs, then bypassed good ol' Newie ('cos of a bit of a family emergency with my sister) and had to pop down to Rye, and got home about 5 hours ago. I'm sure you'll appreciate I couldn't be stuffed ATM getting all the references together, and try to put together a somewhat logical explanation. Geez that bed of mine is looking bloody good right now. There's meant to be a street brewers get together this arvo at 3 pm, but I get the feeling if I go, the first 2 mouthfuls will have me snoring and really impressing the hosts! I'm getting way too old for this sort of stuff. Then if you add about 80m elevation above sea level' date=' where I live, that takes off almost 0.3°...[/quote'] I think I'll leave your elevation out of it, but thanks for the offer. Cheers mate. Link to comment Share on other sites More sharing options...
Xenon Posted September 5, 2015 Share Posted September 5, 2015 . Just as an aside' date=' my FV has a nice Krausen on it now, I was a little worried when I checked it this morning as it was as flat as a tack, usually I see a good krausen within 6-10 hours but it's fine now. I thought one of the points of rehydrating the yeast was to give it a quick start, but then US05 can be a bit of a slow starter so next time I'll use nottingham and see how that goes. One other thing though, the wort is quite dark, almost black, hopefully it loses a lot of that colour during ferment as it looks more like a stout at the moment...smells okay though [img']biggrin[/img] well just a quick update on this one ... the next day after I posted this, my fermenter was exhibiting the most amazing and active fermentation I have ever seen in any of my brews! The activity in the FV was an awesome sight to see - the chunks of (I assume) cold/hot break/yeast clumps were going around and up and down inside there like it was being stirred by something - none of my previous brews exhibited any action like this, just a biggish Karausen forming and subsiding over time. Not sure if it's just because of the all grain wort or maybe the rehydration of the yeast but boy was it great to see. The colour has also lightened up nicely now , and the smell is amazing. The really active stuff lasted for 2 or 3 days, and now it just has a beautiful big krausen on top with that lovely golden colour underneath. Following Kelseys posts on this recipe , I will probably up the temp on Monday night from 18 degrees to 20 or so , cold crash on day 12/13 and bottle a week later. SO looking forward to this one, probably moreso almost than my first ever brew, and that's saying something! But on another subject, next brew ... really want to put out an IPA next. Any of you crown urn guys got a recipe that worked well? I played with a few in beersmith, but it looks like most want a grain bill of 7-8 kG ... can the crown handle that much? I'd like an IBU in the 60 -70's or so if possible...also still have plenty of Magnum and Perle left - if you have a recipe that can use them it would be handy too... Link to comment Share on other sites More sharing options...
Otto Von Blotto Posted September 5, 2015 Share Posted September 5, 2015 Nice one mate! Good to hear. The urn will handle that size grain bill yeah, however I've never brewed an IPA so I can't help with a recipe. Link to comment Share on other sites More sharing options...
Dozer71 Posted September 6, 2015 Share Posted September 6, 2015 But on another subject' date=' next brew ... really want to put out an IPA next. Any of you crown urn guys got a recipe that worked well? I played with a few in beersmith, but it looks like most want a grain bill of 7-8 kG ... can the crown handle that much? I'd like an IBU in the 60 -70's or so if possible...also still have plenty of Magnum and Perle left - if you have a recipe that can use them it would be handy too...[/quote'] In beersmith on the mash page near the bottom it says mash volume needed. If its less than 40 you should be good. Or can use the "Scale Recipe" function to to make a slightly smaller batch and make it fit the urn better. Link to comment Share on other sites More sharing options...
ben 10 Posted September 6, 2015 Share Posted September 6, 2015 Nice one mate! Good to hear. The urn will handle that size grain bill yeah' date=' however I've never brewed an IPA so I can't help with a recipe. [/quote'] I may have. I regularly use over 7kg of malt. Let me know what you have and I'll tell you what I would brew. Link to comment Share on other sites More sharing options...
Xenon Posted September 6, 2015 Share Posted September 6, 2015 Nice one mate! Good to hear. The urn will handle that size grain bill yeah' date=' however I've never brewed an IPA so I can't help with a recipe. [/quote'] I may have. I regularly use over 7kg of malt. Let me know what you have and I'll tell you what I would brew. well I dont have really much on hand at the moment, just 80g of magnum and 80g of perle. Doesn't matter too much about a recipe that uses those as I can just go buy some more when I have my grain bill sorted , just would be nice to use them up while they're fresh. I figure the higher a SG brew I want, the smaller I have to scale back the batch size? Which isn't a problem as a lot of my extract batches were only 21 litres so maybe I just have to set that in beersmith and scale recipes accordingly...?(as Dozer said) Link to comment Share on other sites More sharing options...
ben 10 Posted September 6, 2015 Share Posted September 6, 2015 I figure the higher a SG brew I want' date=' the smaller I have to scale back the batch size?[/quote'] Not really. I get a drop in efficiency the higher I go but that is all good. I'd go 20g magnum @60 all the Perle @ flameout for a 20 minute steep, then whatever other hops you want also @ flameout to reach IBUs to match the OG. Example 7kg of base malt would get me about 1072 so I'd aim for 72 IBU, most of that from flameout additions. Go heavy with the dry hop too. Centennial, citra whatever you feel like. For IPAs I like going say 5kg Pale, 1 kg Munich II and 250 caraaroma and maybe some wheat. Link to comment Share on other sites More sharing options...
headmaster Posted September 7, 2015 Author Share Posted September 7, 2015 With a grain bill that large, i'd be looking to reduce the strike water amount by about 3-4 litres, and make it up by heating up the same amount and sparging the bag, using a pot on a burner, or a couple of electric kettles worth (don't use a plastic kettle...) but only heat to say 78c for the sparge water. Was half thinking of an IPA soon myself, was looking to research a Stones IPA or Dogfish Head 60 min or 90 min IPA recipe. Link to comment Share on other sites More sharing options...
headmaster Posted September 7, 2015 Author Share Posted September 7, 2015 By the way' date=' I think you may be slightly out with the 102°c for the 1040, from my calcs it's closer to 100.2°c.[/quote'] I haven't missed this one, BTW, Chippie. I just recalculated it, and I still get about 102C. Will have to re-visit this then! Would be good to make a 3 axis chart or have a spreadsheet calc that includes temp at boiling, SG and Barometric pressure. Handy to know what the boil temp should be really only for checking thermometer calibration I think. Link to comment Share on other sites More sharing options...
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