NFD ,
Your bit about ginger beer plants , in the 1950's & 1960's mum used to make her own ginger beer starters .
Using a sterile wide necked jar that had a good lid but not air tight such as a quart Kilner jar ( use Milton to sterilize ), 1/2 a pint of cooled boiled water that has two table spoons of sugar dissolved in it , cooled to just tepid temp , a small knob of bakers yeast to crimb sprinkle in the syrup and several spoons of ground ginger . Once stirred up it was covered with the lid loosely on and set in the airing cupboard . ferment on a deep tray . then on day two she'd give it a stir , same with day four, six & eight .
By then it would have started to ferment we could see the CO2 gas bubble coming off if we tapped the jar with a wooden spoon .
Mum would then feed the jar with a little stirred in sugar syrup and two teaspoons of ground ginger for a month by which time the jar would be well over 3/4 full of ginger beer plant it was then ready for harvesting & making ginger beer for us four kids during the summer holidays .
Occasionally she'd keep a third of the sediment back before she washed the rest of the sediment in warm cooled down boiled water so as to not kill off the yeast cells and use that as the starter for the next batch .