Skip to content

Flagstaff IPA No.2


The run of pilsners that I've brewed has come to a temporary end because I fancy doing some ales and as such I've bought in my favourite ale yeast strain.

I've brewed plenty of times with the Conan strain before from The Yeast Bay and Omega but never the Imperial offering. I've made up a 1.5 litre starter and will save back 500ml in the fridge for future brews as I plan to keep this packet on the go for a run of at least four ales before I switch back to pilsners again.

The starter was placed in the brew fridge and set to 20C. The next day I took a look to see how it was getting on.

There's a nice looking krausen this morning, the day after pitching the yeast, and it's giving off the best smell I've ever experienced from a starter. A really full, juicy, peachy aroma.

Brew day

It's brew bank holiday! Well, it's not like I'm going anywhere special so I might as well get cracking in the brewery. Today's brew is a small variation on my Flagstaff IPA that I enjoyed last year designed around the English hops that I've got in the freezer. Here's the modified recipe:

Recipe Specifications
Recipe: Flagstaff IPA No.2
Batch Size (fermenter): 24.00 L
Estimated OG: 1.043 SG
Estimated Color: 11.0 EBC
Estimated IBU: 31.5 IBUs
Brewhouse Efficiency: 75.00 %
Est Mash Efficiency: 75.6 %
Boil Time: 60 Minutes
Finished water profile: Ca:52, Mg:8, Na:9, SO4:72, Cl:57

Amt              Name                                               Type         %/IBU 
29.54 L          Tesco Ashbeck                                      Water        -     
1.70 g           Calcium Chloride (Mash)                            Water Agent  -     
1.70 g           Gypsum (Calcium Sulfate) (Mash)                    Water Agent  -     
1.50 g           Epsom Salt (MgSO4) (Mash)                          Water Agent  -     
3.71 kg          Maris Otter (Crisp) (7.9 EBC)                      Grain        85.0 %
0.44 kg          IREKS Munich Malt (20.0 EBC)                       Grain        10.0 %
0.22 kg          Barley, Flaked (Thomas Fawcett) (3.9 EBC)          Grain        5.0 % 
0.40 g           Calcium Chloride (Sparge)                          Water Agent  -     
0.40 g           Gypsum (Calcium Sulfate) (Sparge)                  Water Agent  -     
0.30 g           Epsom Salt (MgSO4) (Sparge)                        Water Agent  -     
14.00 g          Challenger [6.30 %] - Boil 60.0 min                Hop          10.3 IBUs
11.00 g          Challenger [6.30 %] - Boil 15.0 min                Hop          4.0 IBUs
11.00 g          East Kent Goldings (EKG) [4.10 %] - Boil 15.0 min  Hop          2.6 IBUs
16.00 g          East Kent Goldings (EKG) [4.10 %] - Boil 10.0 min  Hop          2.8 IBUs
16.00 g          Endeavour [8.50 %] - Boil 10.0 min                 Hop          5.8 IBUs
1.00 Items       Whirlfloc Tablet (Boil 7.0 mins)                   Fining       -     
23.00 g          Challenger [6.30 %] - Boil 5.0 min                 Hop          3.4 IBUs
23.00 g          East Kent Goldings (EKG) [5.00 %] - Boil 5.0 min   Hop          2.7 IBUs
1.0 pkg          Barbarian (Imperial Yeast #A04)                    Yeast        -     

Mash Schedule: Single Infusion, Medium Body, Batch Sparge
Total Grain Weight: 4.37 kg
Name              Description                             Step Temperat Step Time  
Mash In           Add 24.54 L of water at 70.5 C          67.0 C        60 min     

Sparge: Dunk sparge with 5 L of water at 75 C

The last 5 minute hop additions were meant to be Endeavour & EKG but upon opening the freezer I realised I didn't have enough Endeavour left so I used Challenger instead. On the plus side I found 50g of Fuggles that I'd forgotten about while rooting around in the freezer so that'll feature in a later recipe.

Brew day itself went fine. I mashed in at 67.5C and left it for an hour. Upon taking a gravity reading before the boil I noticed that I got a couple more points out of the Crisp Maris Otter than I've been getting from the Weyermann Bohemian Pils of late.

After boiling for an hour I chilled down to 24C before getting bored and then transferred the lot into the fermenter to collect a total of 24 litres.

The higher than expected mash efficiency carried through to the FG and I ended up with an OG 1.045. If this finishes at 1.007 then I can expect an ABV of 5.0% for this IPA.

The wort is now chilling down to 19C in the brew fridge before I pitch the Imperial A04 starter. 500ml of that 1.5 litres starter has already been transferred to a Kilner jar in the fridge for the next brew.


Today was kegging day after a total of 16 days in the fermenter. A little over the 14 days that I normally leave it due to other things to get done around the house first. The Imperial A04 Barbarian yeast absolutely ripped through this wort and was definitely almost done after four days and probably complete after a week but I like to leave it to sit and settle out to minimise trub in the corny.

FG was 1.009, up on my usual 1.005-1.007 range due to the mash temperature being 67.5C, about a degree or two warmer than I usually mash at. ABV is 4.8% and the sample tasted promising, very English in character.

The corny was fined with Kwik-Clear, purged with 5x15psi and is now sitting at about 10psi to carbonate and condition over the next couple of weeks.

Tasting notes

Well after all my whinging about the Imperian Barbarian A04 yeast that I used in my Flagstaff IPA No.2 being a slow flocculator I forgot to post a piccy of the beer itself, so here it is.

I still prefer my first version of this brew, the Endeavour hops really do it for me and I really must buy some more. Plus I don't think Maris Otter needs Munich malt and could easily stand alone here. Nevertheless this has turned out to be a really drinkable English IPA with the characteristic full mouthfeel that you get from the Vermont yeast.