On the 'ish forum, we were discussing different kinds of yeast that can be used in brewing. Last year I used lager yeast (from a beer kit) throughout the year, keeping a bit from the bottom of the bucket after each brew and using it to start the next one. This year, not having a beer kit to hand, I looked at sachets of brewing yeast, decided that a pound for a little sachet of yeast was a bit excessive, and bought bread yeast instead, which is much cheaper. I think at least one person in that forum conversation was a bit horrified by my inappropriate yeast!
So far, I've had excellent heather ale and elderflower champagne from that yeast, but I none of the wine is ready yet, so I don't know how that will turn out. Since wine yeast is bred to tolerate higher alcohol concentrations, the bread yeast is likely to give up the ghost at about 12% abv, possibly before all the sugar's fermented. This is fine, as I'm not aiming for strong wine, but there is some concern that as it struggles in the toxic, alcoholic environment, it might produce off flavours.
In the interests of science, and taking advantage of the abundance of blackberries, I decided to make a second batch of blackberry wine, this time investing in a sachet of wine yeast. For my record, here are the details:-
- Two 2 gallon batches, each made with 8 lb blackberries and 2 kg sugar.
- The first batch uses bread yeast, previously used for mugwort ale and
washedin sugar and water in between. The second batch uses half a 5g sachet of Young's red wine yeast.
- For the first batch, berries were picked on Sun 17th and Mon 18th Aug (4 lb each day); fermentation of 1 gallon started on Sun.
- For the second batch, berries were all picked on Tue 19th Aug and fermentation started that day.
- The first batch went into demijohns on Sat 23rd Aug and the second batch on Mon 25th Aug (late in both cases)
By chance, I used two different types of airlock for the two batches, so I can use that to identify them. The ones on the left, with the old, one piece airlocks, are the first batch, with bread yeast. The ones on the right, with the new, two piece airlocks, have wine yeast. I'd only just filled the second batch, so you wouldn't expect it to be frothy yet, but in the buckets, it did seem that the bread yeast was a lot more lively. I suppose it's bred to produce bubbles, so maybe that's not terribly surprising.
These will stay in the (relatively) warm kitchen for a few days before I take them down to the cooler store room. I might even take the first batch down first, to keep everything as similar as possible. Then we'll just have to wait and see what happens. I will conduct blind taste tests, and I'll let you know the results in a few months.