Culturing Lacto for future use

[acarter5251]

I was thinking about brewing something with a little bit of souring during the mash, but not sure when I'll get around to it. Is it possible to culture some lacto by adding grains to a sugar solution, allowing the pH to drop so that only the lactobacillus remain, then refrigerating the culture until I am ready to pitch?

Thanks in advance!

 

[MileHighBrewer]

Lots of people make starters this way. Storing it would be fine.

 

[acarter5251]

Thanks! I figured it shouldn't be a problem if you can do it with yeast, but wanted to make sure before I go and do it.

Is it absolutely essential that you hold the temperature at around 100 degrees the whole time, or can it be done at closer to room temperature?

 

[kingwood-kid]

There is a huge variety of things on the grain; lacto, enteric and other bacteria, wild yeast, probably some mold, maybe even Ebola. Dropping the pH and having some alcohol in there will favor things that won't kill you but will make tasty beer. However, you'd need a pretty advanced lab to identify what was there in the beginning or what survived. I have made beer this way, and it was really sour and pretty tasty, if a bit unpredictable.

 

[acarter5251]

I'm fine with unpredictable as long as it sours in a good way and not in a puke/nasty way haha

 

[mnick12]

Apple juice, peptone, and water adjusted to sg of 1.025 and a pH 6 ( my store bought juice is at 3.1!) grows acidophilus very very well in my experience.

But like kingwood-kid said you really dont know whats on your grain. Instead consider using probiotic pills that contain various lactic acid bacteria, many people have had good sucess with this method and you know exactly what you are getting.

As far as tempurature and storing, most bacteria are not as hardy as yeast and do not like abrupt tempurature swings. That being said the fridge is probably OK, but you may reduce the viability of your culture. Also try to keep the culture as fresh as possible, bacteria can die off quite quickly.

 

[acarter5251]

I've had the culture going for about a day at around 100 degrees now. I cracked the jar open today to check how things were going and it had a little bit of a vomit smell. Is it too far gone, or will the green apple smell come along as the pH becomes lower?

 

[kingwood-kid]

A low pH and some alcohol should get rid of whatever is causing that vomit smell, probably enteric bacteria. Should. I'm not guaranteeing anything.

 

[jnacey]

I've had the culture going for about a day at around 100 degrees now. I cracked the jar open today to check how things were going and it had a little bit of a vomit smell. Is it too far gone, or will the green apple smell come along as the pH becomes lower?

You're likely smelling butyric acid. It smells like vomit because that's the compound that's actually creating the smell in vomit. It's a fairly common occurrence when culturing off of grain.

A cool thing is most strains of brett will metabolize butyric acid into ethyl butyrate, which smells/tastes like pineapples and mango. Once your culture grows, you could toss it into some wort and hold it around 95F for a few days to grow acidity, and then toss in a blend of sacc/brett to finish it off. Should be a nice, acidic, fruity beer.

 

[Dogue]

In my experience it helps to limit oxygen to the starter, when you're growing it keep it around 110F, and step it up several times to lower the pH and kill the other bacteria. When not planning to use it for a beer, I just keep it in a mason jar at room temperature and add a little wort to it every few months. When I want to use it for an upcoming brew, I'll add starter wort to it a week before and keep it around 110F, then pitch it into the fermenter, which I likewise try to keep around 110F for a few days. If I'm doing a Berliner Weisse, after the gravity and pH have dropped a bit, I'll remove the heat and pitch Brett (typically a Brett Drie variant). I've also done Flanders Reds where after a bit of of warm lacto time, I'll pitch sacc and brett. The Berliner Weisses I've made really fully develop their tartness in the bottle, and I've done them as quickly as three weeks in the fermenter before bottling. The Flanders Reds I will typically let go for several months in a plastic fermenting bucket, which helps give a mild acetic character typical of Flanders Reds.