Kettle Sour Procedure:
1) Mash at normal temp (67 C), boil for 15 min to sanitise.
2) Cool to 40 C, test pH and adjust to pH 4.5 with lactic.
3) Pitch yoghurt and purge with CO2, ferment at 40 C with heat wrap till pH 3.5
Batch #4 - 3/12/20 (Eff.: 68 %, Att.: %, ABV: %)
Made for the guys at Evolve Espresso
- Mash vol.: 31.5 L, Pre (sour)-boil vol.: 29 L, Batch vol.: 23 L
Substitutes:
- Gladfield Red Back (500g) in for Carared (550g)
- Wai-iti (finally got it) in for Riwaka, straight swap
- Everything else the same as previous
Pre-soured with 13 ml of Lactic acid (88%) and left for 48 hrs.
10/12/20 - SG: 1011 (Tilt), upped temp to 22 C
11/12/20 - SG: 1010 (Tilt)
12/12/20 - SG: 1009 (Tilt), added vanilla extract (Queen brand), rose water and frozen raspberries (1.5kg) before cold crashing.
Batch #3 - 19/01/20 (Eff.: 61 %, Att.: 75 %, ABV: 4.9 %)
- Mash vol.: 31.5 L, Pre-boil vol.: 28 L, Batch vol.: 23 L
Substitutes: Dropped pilsner malt down to 5 kg from 5.5 to bring ABV down a bit and make it a bit more 'sessionable'.
- pH 5.87 (still dropping slowly), added 10 ml (88%) lactic acid to pH 5.04, added another 3 ml to pH 4.89, added another 2 ml. (15 ml in total), pitched 2 table spoons of yoghurt, purged with CO2 and set temp to 39 C.
21/01/20 - Boiled at 10:30 AM, 27 L volume. Cooled slowly to 20 C as the day was fucking stinking hot and the pool and ground water were warm, dry pitched x2 US-05 into non-aerated wort (I'll see if this affects the beer)
24/01/20 - SG: 1021
27/01/20 - SG: 1014
28/01/20 - FG: 1013, 1.5 kg of frozen raspberries added, cold crashed.
01/02/20 - Kegged and carbed, PSI for 2:45 min.
Added: 15 ml of Rose water and 30 ml of vanilla extract
05/02/20 - This one is a banger, could be the tastiest one yet.
Batch #2 - 13/10/19 (Eff. 65%, Vol. 22.5, Att. 80%)
- Added potassium metabisulfite to this batch pre-mash.
- pH 5.87 (OG: 1051) - 12 ml Lactic acid to bring pH to 4.9
- Same heating set up and water profile as Batch #1
15/10/19 - After 48 hrs pH 3.79, tastes same as first batch (strangely) with a little funky peach, ferm. temp. sat around 37 C for that time.
- Had to cut the boil down to about 35 min as I was rushed to finish, dry pitched x2 yeast to aerated wort.
25/10/19 - FG: 1011, added 1.5 kg frozen raspberries, tasting quite sour but nothing crazy.
1/11/19 - Cold crashed
3/11/19 - Kegged and carbed through purged line and keg. Seems to taste a little 'heavier' than the first but probably just confirmation bias on the higher ABV. Cafe boys tasted slight biscuit malt finish.
Procedure - https://www.homebrewersassociation.org/how-to-brew/funkwerks-5-tips-kettle-sours/
Batch #1 - 30/06/19 (Eff. 61%, Vol. 21 L, Att. ??%)
- OG: 1050 after 15 min sanitise boil, pH 5.42, added 5 ml Lactic acid 88% (drops to pH 5.00), added another 4 ml Lactic (drops to pH 4.80)
- Used heat wrap and temp controller set to max. (39 C) and left covered in lounge room.
1/7/19 - pH 3.75 at 5 PM (26 hrs) mildly sour with a fruity (maybe peach sweet tea) flavour, not bad at all, left it carry on for a few more hours.
2/7/19 - pH 3.57 at 8 AM, tasting still of peach tea and smells like wet malt and damp dog. Boil started at 8:15 AM, boil shortened to 50 min, chilled and aerated, x2 packs of yeast dry pitched and aerated again after 40 min.
10/7/19 - SG: 1019 (hyd.) 1034 (refract.), tastes pretty sour, added 1.5 kg of raspberries loose and it started bubbling again pretty hard overnight.
11/7/19 - Cold crashed to 1.5 C
13/7/19 - Added 30 ml Vanilla extract and 15 ml of Rose water, kegged and carbed at 30 psi for 2:30 min. Tastes of raspberry up front with subtle vanilla and a hint of rose water. Terrible idea to add the raspberries without a hop sock, they are wreaking havoc with the keg poppets and taps.
Substitutes
- Gladfield Pilsner instead of Pale Malt
- Gladfield Dark Crystal & Gladfield Shepards Delight (50/50 mix) instead of Simpsons DRC
- US 05 instead of Belle Saison (I hate saison yeast flavours)
Notes (see photo of recipe)
- Riwaka instead of Wai-iti hops.
- Live yogurt to add lacto. only, couldn't get only Lacto yogurt at Woolies, went with Vaalia (as per photos).
- Suggested water profile: CaCl (110ppm) & CaSO4 (55ppm)
- CO2 purge the fermenter and bubble CO2 through it as it sours to drive off 02.