Rinse and pick through blackcurrants, removing any that are moldy, etc. Remove stems and pits, chop them up.
Place in a large pot, along with the sugar. Using a potato masher or VERY clean hands, stir and mash blackcurrants.
Add water, stir well. Heat to ALMOST boiling, then simmer gently for 30 minutes. Stir in acid blend, enzyme, nutrient, and tannin.
Pour mixture into a freshly sanitized fermenting bucket. Cover with sanitized lid and air lock, allow to cool to room temperature (overnight).
The next morning, give the mixture a quick stir with a long, sanitized spoon, and – using sanitized equipment – take a gravity reading of the liquid (strain out any blackcurrants). Keep track of the number! (This is an optional step, but will allow you to calculate your final ABV %)
Sprinkle yeast into fermenter, cover with sanitized cover and air lock. Within 48 hours, you should notice fermentation activity – bubbles in the airlock, carbonation and /or swirling in the wine must. This means you’re good to go!
After a week or so, use your sanitized siphon setup to rack the must into a freshly sanitized carboy. Put the carboy somewhere cool (not cold!), and leave it alone for a month or so.
Using sanitized equipment, rack the wine off the sediment, into a clean, freshly sanitized carboy. Cap with sanitized airlock, leave it alone for another 2-3 months.
Rack one more time, leave it for another 3 months or so.
When your wine has been racked a few times and shows NO more fermenting activity for a month or so (no bubbles in the airlock, no more sediment being produced, you can move on to bottling. **
If stabilizing, follow the instructions on your selected type of wine stabilizer to stop fermentation. For potassium sorbate, this needs to be done 2-3 days before bottling.
Backsweeten your wine, if desired.
Using sanitized equipment, take a gravity reading, then rack the wine into clean, sanitized bottles. Cork.