Zephyr259
Landlord.
TL;DR - I made a batch of Maibock and Best Bitter from a partigyle where I blended the worts pre-boil, conversion efficiency sucked probably because I didn't stir the mash but I got what seems to be two good beers anyway.
I finally got up the nerve to do a partigyle after years of considering trying it out. Decided this was a good brew to try it with as I was brewing a Maibock which wanted an OG of 1.070 ish which is were the grainfather starts to have efficiency problems in my experience. After a bunch of reading and maths I decided to blend the worts pre-boil rather than the more traditional post-boil, this was mainly so I could hop the beers differently as keeping the Maibock with noble hops would have forced me to do the same with the small beer and I already have a styrian goldings lager at the moment.
Grain bill was 2.5 kg each Pilsner and Vienna, 1 kg Dark Munich and 500g Caramalt, base malts were from Bestmalz and the crystal was Simpsons. I was aiming for equal run-offs so 22.7 L for the mash and 17.5 L for the batch sparge, mash was 65c then 75c mash out and the batch sparge was held at 75c and circulated for 15 mins once the grain had been thoroughly remixed. That was amusing as the grain had set in the malt pipe and so floated when it was lowered back into the fresh water, it slowly sank back down as the grains got wet and took a fair bit of stirring to break up the lumps. The first wort was held in my stainless FV while the 2nd runnings were being handled.
This is where the first issue came about, I've been using a mash and lauter simulator someone linked a while back and I usually get a conversion efficiency of 95-98%, this time the numbers imply I was down at 86% so instead of two worts of 17.5L at 1.074 and 1.024 I had the correct volumes but my gravities were 1.062 and 1.022. Think I should have stirred the mash at least once as I took 2 gravity samples from the wort on top of the mash and the wort coming out the recirc pipe and they were 1.068 and 1.073 respectively, so there was a large part of the mash which was much lower gravity than it should have been. Modelling the figures shows that my lauter was 90% efficient so pretty sure it was a conversion issue due to 6.5 kg of grain not being mixed well enough.
From here everything went fine. I altered my blend so that my Maibock was still about the gravity I wanted and the bitter shifted from a 5.4% ESB to a 4.5% Best Bitter which is actually what I'd have brewed if the maths had allowed it. 15L of pre-boil wort was blended 75% strong and 25% weak for the Maibock then boiled for an hour, all hops were Hallertauer Mittlefruh at 3% AA, I like Foxbat's hopping schedule so 6g at 15 min, 8.5g at 10 min and 12g at 5 min (0.5, 0.7, 1 g/L and I based it on my post boil volume this time rather than batch volume), 48.5 g was added at 60 min for a total of 31 IBU and a nice round 75g of hops used. This was then chilled to 10c and Wyeast 2308 Munich Lager was pitched, started bubbling slowly after about 18 hrs.
The remaining worts made 19.5 L for the bitter, it got the same late hop schedule but with a 50/50 split of 7.3% AA Challenger and 7.1% AA First Gold so 4g each at 15 min, 6g each at 10 min and 9g each at 5 mins, 11g each at 60 min gave 30 IBU and 25g of each hop used. This was chilled to 20c and Omega's Vermont strain was pitched. A few hour later I remembered that I was meant to add extra gypsum and table salt to this batch so I sanitised a cup, stirred up the additions in a bit of boiling water and chucked it into FV. The yeast was very happy and was starting by the evening and the airlock was very active the next day, oddly it seemed to be a bit quieter this morning so hopefully nothing's gone wrong.
It was a long brew day, mashed in at 7am and was clean and tidy by 3pm but that's only a couple of hours extra I think and I have 10L of 1.069 Maibock and 15L of 1.045 bitter to show for it so I'm happy. I'll definitely do another partigyle, might be the next brew as my wife has requested a cherry imperial stout so I either keep it simple and just accept the poor efficiency or I see what small beer I can also make. If I'm feeling totally crazy I may do the double mash that's in the Scotch Ale book where you do 2 mashes so you can get enough first running at a high enough gravity to make a huge beer and a small beer. I'd also like to blend post boil to see what that is like and if I can work out how to boil in both my GF and sparge heater at the same time that would speed things up a lot, problem is working out how to cool the stuff in the sparge heater as I only have the GF chiller and it needs a pump and how to handle hops which would probably block the heater's tap.
Hope this was interesting to some folks.
I finally got up the nerve to do a partigyle after years of considering trying it out. Decided this was a good brew to try it with as I was brewing a Maibock which wanted an OG of 1.070 ish which is were the grainfather starts to have efficiency problems in my experience. After a bunch of reading and maths I decided to blend the worts pre-boil rather than the more traditional post-boil, this was mainly so I could hop the beers differently as keeping the Maibock with noble hops would have forced me to do the same with the small beer and I already have a styrian goldings lager at the moment.
Grain bill was 2.5 kg each Pilsner and Vienna, 1 kg Dark Munich and 500g Caramalt, base malts were from Bestmalz and the crystal was Simpsons. I was aiming for equal run-offs so 22.7 L for the mash and 17.5 L for the batch sparge, mash was 65c then 75c mash out and the batch sparge was held at 75c and circulated for 15 mins once the grain had been thoroughly remixed. That was amusing as the grain had set in the malt pipe and so floated when it was lowered back into the fresh water, it slowly sank back down as the grains got wet and took a fair bit of stirring to break up the lumps. The first wort was held in my stainless FV while the 2nd runnings were being handled.
This is where the first issue came about, I've been using a mash and lauter simulator someone linked a while back and I usually get a conversion efficiency of 95-98%, this time the numbers imply I was down at 86% so instead of two worts of 17.5L at 1.074 and 1.024 I had the correct volumes but my gravities were 1.062 and 1.022. Think I should have stirred the mash at least once as I took 2 gravity samples from the wort on top of the mash and the wort coming out the recirc pipe and they were 1.068 and 1.073 respectively, so there was a large part of the mash which was much lower gravity than it should have been. Modelling the figures shows that my lauter was 90% efficient so pretty sure it was a conversion issue due to 6.5 kg of grain not being mixed well enough.
From here everything went fine. I altered my blend so that my Maibock was still about the gravity I wanted and the bitter shifted from a 5.4% ESB to a 4.5% Best Bitter which is actually what I'd have brewed if the maths had allowed it. 15L of pre-boil wort was blended 75% strong and 25% weak for the Maibock then boiled for an hour, all hops were Hallertauer Mittlefruh at 3% AA, I like Foxbat's hopping schedule so 6g at 15 min, 8.5g at 10 min and 12g at 5 min (0.5, 0.7, 1 g/L and I based it on my post boil volume this time rather than batch volume), 48.5 g was added at 60 min for a total of 31 IBU and a nice round 75g of hops used. This was then chilled to 10c and Wyeast 2308 Munich Lager was pitched, started bubbling slowly after about 18 hrs.
The remaining worts made 19.5 L for the bitter, it got the same late hop schedule but with a 50/50 split of 7.3% AA Challenger and 7.1% AA First Gold so 4g each at 15 min, 6g each at 10 min and 9g each at 5 mins, 11g each at 60 min gave 30 IBU and 25g of each hop used. This was chilled to 20c and Omega's Vermont strain was pitched. A few hour later I remembered that I was meant to add extra gypsum and table salt to this batch so I sanitised a cup, stirred up the additions in a bit of boiling water and chucked it into FV. The yeast was very happy and was starting by the evening and the airlock was very active the next day, oddly it seemed to be a bit quieter this morning so hopefully nothing's gone wrong.
It was a long brew day, mashed in at 7am and was clean and tidy by 3pm but that's only a couple of hours extra I think and I have 10L of 1.069 Maibock and 15L of 1.045 bitter to show for it so I'm happy. I'll definitely do another partigyle, might be the next brew as my wife has requested a cherry imperial stout so I either keep it simple and just accept the poor efficiency or I see what small beer I can also make. If I'm feeling totally crazy I may do the double mash that's in the Scotch Ale book where you do 2 mashes so you can get enough first running at a high enough gravity to make a huge beer and a small beer. I'd also like to blend post boil to see what that is like and if I can work out how to boil in both my GF and sparge heater at the same time that would speed things up a lot, problem is working out how to cool the stuff in the sparge heater as I only have the GF chiller and it needs a pump and how to handle hops which would probably block the heater's tap.
Hope this was interesting to some folks.