Peach Jalapeño Kettle Sour

[ShowPonyBrewing]

If using fresh peaches that have been frozen for a kettle sour, do you need to heat pasteurize the fruit prior to using as well? Also how much jalapeño should we use for a small hit of it?

 

[RPh_Guy]

Freezing doesn't kill the wild microbes, so it's a good idea to pasteurize if you want to keep the beer "clean".

 

[ShowPonyBrewing]

Ok. I also used WLP677 Lacto for souring, anyone know about how long it should take to start dropping the ph?

 

[RPh_Guy]

That strain isn't good for kettle souring.
Keep it 100-110°F and you'll see pH drop over 5-7 days.

http://www.milkthefunk.com/wiki/Lactobacillus

 

[ShowPonyBrewing]

Seems like it’ll work in about 3 days per the chart.

 

[RPh_Guy]

Not all Lacto species/strains behave the same. You need to look at your particular species.
"Sour" beer is generally pH 3.7 or lower.

White Labs WLP677 L. delbrueckii (might be misidentified [26])
"Incubate at > 90°F and < 117°F for 5-7 days for greater lactic acid production. Cell count: 50-80 million cells/mL (1.75-2.8 billion cells in a 35 mL homebrew vial) [23]. Not a good strain for kettle souring, but can produce a "soft" acidity over a longer period of time [28]. White Labs claims that it is tolerant to up to 20 IBU, although growth starts to become inhibited at 15 IBU [29][30]. Generally heat tolerant, but sours faster between 100-110°F [29]"

http://www.milkthefunk.com/wiki/Lactobacillus#pH_change_at_108.C2.B0F
L. delbrueckii never took the wort into sour beer territory in various experiments (and white labs often has yeast contamination in their bacteria products).
I'd suggest using L. plantarum for kettle souring.