Clibit
Lots of good info about making sour fruit beers in this article with a recipe which uses Yakult as the lactobacillus source. 

https://byo.com/article/catharina-sour-brazilian-kettle-soured-fruit-beer/


Catharina Guajava

(5 gallons/19 L, all-grain)
OG = 1.047 FG = 1.008
IBU = 9 SRM = 3 ABV = 5.2%

Ingredients
6 lbs. (2.7 kg) Pilsner malt
3 lbs. 8 oz. (1.6 kg) wheat malt
3 AAU Magnum hops (30 min.) (0.25 oz./7 g at 12% alpha acids)
5.5 lbs. (2.5 kg) fresh guava, peeled, frozen, then thawed
(3) 80 g bottles “Yakult 40” brand probiotic drink (Lactobacillus casei Shirota)
SafAle US-05 or other clean, highly attenuative ale yeast
7⁄8 cup corn sugar (if priming)

Step by Step
Adjust brewing water with lactic acid, calcium sulfate, and calcium chloride to achieve a mash pH of 5.3 with 70ppm of calcium and a sulfate:chloride ratio of 1:1. I would use reverse osmosis (RO) water and adjust all brewing water to a pH of 5.5, then add ½ tsp of calcium sulfate and calcium chloride to the mash.

This recipe uses a step mash with rests at 122 °F (50 °C) for 5 minutes, 153 °F (67 °C) for 70 minutes, and 169 °F (76 °C) for 10 minutes. Sparge and collect 6.5 gallons (24.5 L) of wort.

Boil the wort for 10 minutes to sanitize without hops, then chill to 113 °F (45 °C). Acidify with lactic acid to a pH of 4.5. Pitch the Lactobacillus (probiotic drinks) directly into the boil kettle. Seal the boil kettle using plastic wrap. Purge with CO2 periodically. Keep the temperature at 113 °F (45 °C) using an electric heater or other method for 36 hours or until the pH reaches 3.5. Perform a second boil for 70 minutes, adding the hops with 30 minutes remaining. Chill the wort to 64 °F (18 °C), pitch the yeast, and ferment until SG 1.014. Add the guava and allow fermentation to finish.
Clarify if necessary. Rack the beer, prime and bottle condition, or keg and force carbonate.

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Robbie
wow thats a full blown sour mash, I love guava too.  Gordon Strong has amazing recipes.  He meditates in his mind what the beer would taste like and then tries to formulate recipes based on his imaginations, a truly phenomenal approach.
Beer is an expression of the human spirit. . . we use technical sciences as a tool to create it but its essence is and always will be a form of art - Handbook of brewing, chapter 2, page 55
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Clibit
MSK wrote:
wow thats a full blown sour mash, I love guava too.  Gordon Strong has amazing recipes.  He meditates in his mind what the beer would taste like and then tries to formulate recipes based on his imaginations, a truly phenomenal approach.


Hey, I do that too.   [rofl]
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Robbie
Clibit wrote:


Hey, I do that too.   [rofl]


wow thats amazing to my mind, you need to know what the individual ingredients will bring.  He likes to use a mixture of pale malts, for him Marris Otter is fairly 'nutty', but he likes the malt backbone it brings so he might mix it with other pale malts like Pilsner malt, then thinks about mouth feel and other stuff, then hops and its all swirling about in his mind before he has measured out a single grain.
Beer is an expression of the human spirit. . . we use technical sciences as a tool to create it but its essence is and always will be a form of art - Handbook of brewing, chapter 2, page 55
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Clibit
MSK wrote:


wow thats amazing to my mind, you need to know what the individual ingredients will bring.  He likes to use a mixture of pale malts, for him Marris Otter is fairly 'nutty', but he likes the malt backbone it brings so he might mix it with other pale malts like Pilsner malt, then thinks about mouth feel and other stuff, then hops and its all swirling about in his mind before he has measured out a single grain.


I think we who make our own recipes all do it to an extent, but I don't claim to be anything like as sophisticated or knowledgeable as him. 
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