'Feeding' the GBP

Hi y'all,

I'm a novice ginger beer plant enthusiast, and started my second generation of experimental Ginger beer plants (GBP) and started having fun geeky chats about it with a friend who brews his own beer.

I get the impression his beer-brewing antics are much more refined and exacting than mine, but he asked me a funny question I realised I couldn't answer:

'Why do ginger beer plants need to be 'fed' daily, why not put seven days worth of ginger and sugar (basics) at the start and let it run its course?'

I have one batch busy putting that to the test, but I'm curious if anyone out there knows the technical/sciencey reason for this method of growing GBPs??

I've never used GBP and in fact had to look up what it even is, but I can guess at an answer. I think it might be because too much sugar doesn't allow for enough nutrients. It's like making mead. You don't want to just add yeast to 20# of honey and water without adding nutrients. Or instead, you can start slow and add honey in increments to allow the yeast to work through fewer fermentables so they stay nice and healthy. But that's just my guess.

Maybe it's like sourdough (which I do know about) where you can't just add pounds of flour to "feed" the sourdough starter because it would probably just die off or not be nearly as healthy is it would be by feeding it small amounts each day.

tommy_boy said:

Hi y'all,

I'm a novice ginger beer plant enthusiast, and started my second generation of experimental Ginger beer plants (GBP) and started having fun geeky chats about it with a friend who brews his own beer.

I get the impression his beer-brewing antics are much more refined and exacting than mine, but he asked me a funny question I realised I couldn't answer:

'Why do ginger beer plants need to be 'fed' daily, why not put seven days worth of ginger and sugar (basics) at the start and let it run its course?'

I have one batch busy putting that to the test, but I'm curious if anyone out there knows the technical/sciencey reason for this method of growing GBPs??

Click to expand...

myndflyte said:

I've never used GBP and in fact had to look up what it even is, but I can guess at an answer. I think it might be because too much sugar doesn't allow for enough nutrients. It's like making mead. You don't want to just add yeast to 20# of honey and water without adding nutrients. Or instead, you can start slow and add honey in increments to allow the yeast to work through fewer fermentables so they stay nice and healthy. But that's just my guess.

Maybe it's like sourdough (which I do know about) where you can't just add pounds of flour to "feed" the sourdough starter because it would probably just die off or not be nearly as healthy is it would be by feeding it small amounts each day.

Click to expand...

Like Myndflyte, I had to look this up and found the Wikipedia article very interesting. Apparently the yeast involved is Saccharomyces florentinus and is known to be pathogenic on strawberry. Well, recently I tried isolating wild yeast from strawberry and came up with a yeast that would ferment beer but would only reduce the gravity by ~2% (perhaps this is Sacc f). So here is my guess, perhaps the Sacc f will only ferment small amounts but if fed more after the initial ferment will continue fermentation and by repeating the feeding over time you have a reasonable amount of EtOH.

Please let us know if you come up with a more solid answer.

I've not yet found a definitive answer, but there recipes out there use everything from dried champagne yeast to fresh bakers yeast....

Still looking...

tommy_boy said:

I've not yet found a definitive answer, but there recipes out there use everything from dried champagne yeast to fresh bakers yeast....

Still looking...

Click to expand...

Thanks for the update. It is my understanding (from web research) there are alternative methods to produce ginger beer but the original method requires a symbiotic colony of a wild yeast and bacteria. Here is what Wikipedia has on the GBP:

Ginger beer plant (GBP) is not what is usually considered a plant but a composite organism consisting of a fungus, the yeast Saccharomyces florentinus (formerly S. pyriformis), and the bacterium Lactobacillus hilgardii (formerly Brevibacterium vermiforme),[5][6] which form a symbiotic colony of bacteria and yeast. It forms a gelatinous substance that allows it to be easily transferred from one fermenting substrate to the next, much like kefir grains, kombucha, and tibicos.[7]
The GBP was first described by Harry Marshall Ward in 1892, from samples he received in 1887.[6][8][9][10] Original ginger beer is made by leaving water, sugar, ginger, and GBP to ferment. GBP may be obtained from several commercial sources or from yeast banks.[11]