Can I use scoby from 1 gal batch to make 2.5 gal batch?

[otherchuck]

Greetings,

I recently got a kombucha kit which came with a one gallon brewing jar. The two batches I have made so far came out perfect, so now I want to increase the size of the batch. I have a 2.5 gallon glass jar; can I just multiply the ingredients by 2.5 and use the same scoby that I am currently using to ferment a one gallon batch? Sure looks like a healthy, robust scoby to me, and so I presume it will just increase in size as needed for a 2.5 gal batch. Any other tricks I should bear in mind as I increase from 1 gal to 2.5 gal? For instance, does it take about as long to ferment, or should I increase the ferment time by some amount?

Otherchuck

 

[Sajbrewer]

I did the same last year. Did you get a "baby" SCOBY from either of your first 2 batches? Even if you didn't I think you'd be fine. The new SCOBY will grow to the size of the vessel, so you'll like end up with a good sized "baby" from the larger (2.5 gallon) vessel.

I wouldn't worry about proportionally adjusting the timing for the first fermentation. Just go by taste. I start tasting after 5 days or so by dipping a straw past the SCOBY on top. When it's got the right sweet / sour profile you like your good to go. My guess is it will likely take longer, but just keep an eye on the flavor.

 

[shelly_belly]

Use 10% kombucha as a starter for every batch. For 2.5 gallons use 32 ounces kombucha. I never reuse the scoby. Every batch grows a new one!

 

[otherchuck]

Wow, you mean use 32 ounces of my current batch to start the next one? In the instructions that came with my kit (from "The Kombucha Shop") they said that after removing the cultures from one batch and putting it in a glass container, to add one cup of kombucha if I was going to start a new batch right away, or 2 cups if I was gonna wait a few weeks. So I interpreted that as '1 cup starter + scoby' for one gallon, thus '2.5 cup starter + scoby' for a 2.5 gallon batch. Also, I mispoke in my original post: I have brewed one batch that I know came out perfect; I haven't tasted the second batch yte, but will bottle that one as soon once I feel confident about this transition to a 2.5 gal model. I am hoping that sec0ond batch is perfect is well, but...we'll see!

 

[Zimm9]

I didn't buy a scoby but used a store bought bottle of kombucha to get one. My goal was to make 2 batches for gifts, each 2 gallons. I split the store bottle into 2 (quart) jars equally and topped off with sweet black tea. Got a scoby formed in each quart jar and let them ferment awhile. I then made up 4 gallons of sweet tea (mix of black and green) and dumped an entire quart jar into each 2 gal jar. It only took a few days at 75* for a new scoby to start forming in those 2 gal jars. The quart jars took much longer because I had them at 65*.

So, long story short: you can put a small scoby into a large jar. And fermentation time has a lot to do with the temp where you're storing it.

 

[shelly_belly]

I actually use 6% but recommend 10% as that is what all the literature seems to suggest. As your culture adapts to your method you can get by with less starter. 2.5 cups should be fine for 2.5 gallons and would be the least amount I would use.

 

[Sajbrewer]

Just my experience, but I think 1cup starter per gallon works well. Like shelly_belly said, I wouldn't go any less, and I don't think a little more would hurt at all.

 

[DrMoebius]

I've made 2 gallon batches with a White Labs 4" diameter SCOBY that was paper thin. 5 days later, a fairy nice pellicle was covering the entire 9" surface. The company says that SCOBY will easily do an 11 inch 5 gallon kettle.