Hi Michael (& everyone else),
No, I definitely don't add any more sultanas, works absolutely fine with just sugar added for food. You will find that after a few weeks the sultanas cease to be recognisable anyway - the "plant" just looks like something you'd find at the bottom of a pond (but obviously smells much better!). What I did find last summer is that sometimes the bug would get too strong (i.e. would make the bottles fizz too quickly) and if this happened I just halved the bug, fed it for a couple of days, halved it again and then went on as before.
Thanks everyone for your replies. I haven't added any more sultanas, but most of them seem to have ended up in the half of the original plant that I recycled!
As Kate suggested, however, I have been keeping the plant in an air-tight (screw-top) jar. There's certainly a lot of 'movement' when I take the lid off to feed it.
My first batch should just about be ready to taste (I ended up putting it in plastic mineral water bottles to avoid bottle breakage). Will let you know how it turns out!
It's been a few months since I last wrote; thought I'd let you know how my ginger beer turned out.
First of all, when I bottled it, I put it in plastic mineral water bottles (2 litres). This way I avoided the problem of the bottles exploding (the plastic is quite elastic really, and although it does become much harder after a while, I didn't have any disasters due to bottle breakage or leakage). For the third batch, I used smaller bottles (1.5 litres), as when the beer was in the bigger bottles it tended to go flat before I could drink it all.
I ended up making 4 batches. By the time I'd bottled the last one, however, the plant seemed much, much weaker; I was actually going to throw out the last few bottles since the beer didn't seem to be working at all, but I kept it for several weeks, and after about a month it was drinkable.
I am still confused regarding the jar that should be used to keep the plant in. I originally followed Kate's suggestion and used (what I thought was) an airtight screw-top jar. One night, when I got up to get a glass of water from the kitchen, I could hear a hissing noise and thought I'd left the gas on (!!). It turned out to be the ginger beer plant; the lid of the jar wasn't as airtight as I'd supposed. After that I transferred the plant to a jar with a rubber seal under the lid, really airtight. Whenever I opened the jar to feed the plant, there was a lot of activity, but when the lid was on the plant seemed very sedate.
I've just started another plant for Christmas, and after four days it doesn't seem to be doing much (it's in the airtight jar). Therefore I'd like to know if I should leave the lid slightly open, or even take the lid off completely and cover the jar with calico as Chris does. Is air necessary for the fermentation process?
Calico, muslin or just a plain screw-top left on a bit looser is fine - not sure why I said it had to be airtight, as if your bug is weak then it could probably do with some natural yeasts from the air. Mine is going really well, but only on it's second batch for the summer, so early days yet.
great to hear your success! I'm envious - we're in the middle of moving so not the time to start brewing but you've inspired me to get a bug going asap...
My understanding is the bug needs to 'breathe' to ferment, hence the calico or as Kate says a loose-fitting lid. Then when you mix up & bottle it in something airtight, rather than being able to escape, the gas produced either stays in the brew or is forced into the brew, not sure which. Not a very scientific explanation, but that's how it seems it works to me. I've noticed when I've kept a bug sealed (when doing something like transporting it) it gets tired. Your bug will be a lot more lively once it's able to breathe I'm sure.
I've tried plastic bottles in the past & I reckon it takes a bit longer for them to be ready, due to the expansion factor before the bubbles are stuck in there. Again, not v. scientific! I prefer glass as I like to use organic ingredients and avoid plastic as much as possible, but have had some wicked explosions in the past. In the heat of summer bottled G.B. can get explosive pretty quickly. Next time I've decided to store my brew in lidded plastic bins to contain any potential explosions.
Keep us posted on how your Christmas batch goes!
Thanks for your reply.
I've put the bug into a different jar, and the lid is on loosely. It does seem very tired (it didn't get off to a good start!), but I'm hoping it will pick up; I started feeding it yesterday. There's also the fact that it is now winter here, and so the temperature, especially at night, is not really so conducive to a vigorous fermentation.
I don't really like using plastic bottles either, but because we live in a flat and have no garden I didn't want to risk having bottles exploding. Here in Italy, home-made (or even commercially produced) ginger beer is practically unknown and so I was hoping to have some ready for my wife's relations to taste at Christmas. We'll see what happens, and I'll let you know.