The question was perhaps more related to what is the purpose of the tannin in relation to a batch of skeeter pee? Just for taste, or for the purpose of some chemical reaction?
In any case, I started my batch 12 hours ago and it's already fermenting. Not sure how long it's been fermenting because I was asleep. It doesn't seem to be as hard to get going as I had been led to believe.
To begin with, I had a 20 liter demijohn full of 8 day old cider that had been fermented with a new packet of Kitzinger's Reinhefe Champagner yeast and about 50g of DAP/nutrient mix. This batch was almost finished anyway, to the point that I would have racked and split it for clearing in order to free up my demijohn.
First, I siphoned off about 1 liter of the heavy yeasty cider into a small jug for later usage. Next, I racked the rest of the batch into 4 smaller glass jugs and airlocked them, leaving behind about 1.5 liters of slurry. This 1.5 liters of slurry will be split in two: half to the skeeter pee batch and half to a new batch of cider going into the same demijohn.
How I did it in a 5 gallon carboy (didn't have a bigger vessel free at the moment):
1. sugar inversion with lemon juice as per the recipe (thanks SWMBO)
2. two liters of lemon juice from little plastic bottles as per the recipe
3. topped with water to 28C liquid temp, leaving about 2.5 liters of free space
4. half of the yeast slurry from the above batch of cider (about 750ml)
5. added 750ml of the above yeasty cider that was set aside
6. about 50g of DAP/nutrient mix
Airlocked her and let her go. There's about 1 liter of headspace remaining, so the last 1 liter of lemon juice will fit in when the batch drops down to about 1.050.
So, I didn't exactly follow the recipe but anyway it's actively fermenting in less than 12 hours.
And I immediately started a new batch of cider in the demijohn on top of the 0.75 liters of slurry from the last batch, along with about 50g of DAP/nutrient mix. This morning, it is already in extremely active fermentation.
Waiting for the skeeter pee!