Gyle Interrupted APA 18.03.15

This is an APA version of the Optic Extra Pale recipe, with loads of Chinook and Centennial late in the boil, and a decent dose of Amarillo in the fermentor. Optic base malt was not available, so I went with Maris Otter instead. Otherwise, the grain bill, mash profile, and other details are identical. I also used lactic acid to acidify the mash and sparge water, and added a very small dose of gypsum to the mash.


Everything went according to plan on brew day, until the city decided to do some water main repairs and shut down my water supply in the middle of the mashout. At this point, I wasn’t sure whether to dump everything and buy new grains, or hold the mash at 75C and wait for the water service to resume. I opted for the latter, and fortunately had to wait only a few hours. In theory, all relevant enzymes should be denatured at this temperature, but it will be interesting to see whether the finished product has any characteristics that could be attributed to the monster mashout.

When it comes to the brew day numbers, I had very high extraction efficiency by my standards, at 80%, which makes some sense, plenty of time for any sugars to dissolve. There were no problems with sparging, although I did need to vorlauf for quite a long time before I saw reasonably clear wort.


After the boil I actually had a little too much volume, so I ended up hitting the predicted OG right on the nose, despite the higher efficiency.

Recipe Specifics
Batch Size: 9L
Boil Time: 60 min
Estimated OG (brewtoad): 1.056
Measured OG: 1.056
Estimated FG: (brewtoad) 1.013
Calculated FG: 1.011
Estimated IBU (brewtoad): 44
Estimated SRM (brewtoad): 4
Estimated Extract Efficiency: 75%
Measured Extract Efficiency: 80%

Grain Bill
2100g Maris Otter (Thomas Fawcett)
200g Toasted Flaked Barley
100g CaraHell (Weyermann)

Mash Schedule
Saccharification rest for 60 min at 66.5C, 2.7L/kg, with 1/8 tsp gypsum and 1/8 tsp 88% lactic acid. Mashout for 15 min (2 hours) at 75C. Sparge to 11.5L and top up to 13L.

10g Chinook 13% AA @ 60 min
10g Chinook 13% AA @ 10 min
15g Centennial 9% AA @ 5 min
10g Chinook 13% AA @ 0 min
15g Centennial 13% AA @ 0 min
30g Amarillo Leaf 9% AA @ Dry Hop (Day 8 – Day 14).

WLP001 California Ale @ ~8.5 Million Cells/mL

Fermentation Notes:
18.03.15: Yeast pitched, temp at 17.5C.
19.03.15: Lovely small white krausen, temp at 18C.
23.03.15: Small krausen still going, temp at 18.5C.
25.03.15: Krausen subsiding, temp at 19C.
27.03.15: Dry hops in, temp at 19C.
31.03.15: Bottled 7.7L with 58g of table sugar (2.8 Volumes).


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