Hi guys, I've tried to brew German Dopel Bock under recipe bellow and got very low o.g. Instead of getting (estimated) 16°P I've got ridiculously low 11,5°P. Any suggestions/ideas what I'm doing wrong? Quantity: 50 l Malt: 2,00 kg Pilsener malt 4,00 kg CaraBlond - Castle Malting 4,00 kg Munich - Castle Malting 0,90 kg Acid malt 0,20 kg Black - Castle Malting Hops: 40 gr Styrian Aurora, 5 min. 29 gr Magnum, 40 min. 12 gr. Perle, 70 min. Yeast: 15 gr S04 (Fermentis) Water: 50 l main cast 5 l lauter Mash in 45 ° C. Protein mode 55 ° C - 20 min Maltose pause 63 ° C - 35 min Sacharification 72 ° C - 25min Mash out 78 ° C Boiling: 75min 1 hops 5-10 min after the start of boiling 2 hops 5 min before end of cooking
A couple of things stand out (I guess this is about a 35L batch?): I see acid malt of over 7% of grain bill. Do not know your water profile but this is a massive addition and suspect your ph is very low. This will effect efficiency, especially at extreme levels. Will let others more knowledgeable in this area chip in. Not familiar with CaraBlond, but from Castle's website it appears to be normal carmel-style malt . . . you are at 36% which is a huge amount. Castle recommends no more than 20% and for a Doppelbock this is normal closer to zero. Your mash temps are at the ends of the alpha/beta amylase range. Typically the range is 62 - 67C and 71 - 72C. You are in the range, but no room for error if you miss your temperatures. A couple of measuring questions: Did you adjust your OG based on temperature (hotter wort shows a lower OG) and is your thermometer/hydrometer calibrated?
As Portlargo has said 0.90 kg acid malt will put your mash pH very low, even if your brewing water Alkalinity was around 500 mash pH still would be under 5,2. This could be the main culprit of the low efficiency.Why did you add so huge qty.?
Hi all, Thanks for your replies & suggestions. I haven't been around so, only just now able to check this thread. So, here is the deal: In the meantime I've brewed another batch, this time NO ACID malt. Checked my pH after mashing and it was 5.3 (what is pretty fair). Instead of CaraBlond I've used Melano (also Castle) and replaced 0,9 kg of Acid malt with Pilsner malt. It is 50 liters batch brewed in Speidel Braumeister, and in total my 31st brew with Speidel and it was second attempt for high o.g. beer. All previous batches were also all grain. I've also increased S-04 from 15 to 20 grams. Also have grind malt to finer grade of 0,035 mm (compared to 0,050 mm in previous brew). Those changes provided me with 12,2 °P, but yet still too far from wanted at least 15°P!!!
I'm measuring my gravity at 20°C all the time as I know that's the temp at which those instruments are calibrated (digital pH meter and hydrometer). So, what are you suggestions regarding further improvement of my recipe and brewing temps/times? Thanks!!!
I'm using stainless steel coil, with running cold tap water through (temp. between 15 and 20 °C depending on a part of the year) inserted in to the brewing kettle for crushing. It takes roughly some 30 - 40 minutes for cooling wort from 100°C to a 25°C. After which I'm transferring it to a fermentor, with a lot of aeration in the process. As per grain brewing, I have only 32 brews so far, all of them all grain.
As per one of my replies above, I've left out Acid malt in next brew and replaced it with Pilsner malt and yet got only 12,2°P o.g. at the end...
Are you hitting your volume targets? If you are getting more than 50 l you're diluting the wort. It might not be the main issue, but you might be losing a .5-1 P this way.
I'm ending up with 45 liters. I'm thinking maybe it is too short mash time for all the sugars to be extracted from the grain... Just shooting in the dark right now...
I overlooked this in your original post. Plugging in your grain bill from your first post for a 50L batch gives an estimated OG of 1.046 (11.5P) in the Brewers Friend calculator (based on 72% efficiency). My guess is your calculator has some error issues.
If I remember right, the Speidel Braumeister utilizes what is essentially a no sparge/BIAB type of mash? There is some loss efficiency with these approaches, but it likely is nothing that an extra pound or two of base malt can't cure.
Could this have to do with not having a vigorous enough boil? Not boiling off enough? Knowing your system helps here....maybe boil longer or lower amt of sparge water?
