After following @gfron1's kind advice I now have a first batch of Blackcurrant pâte de fruit. They set very well and it was easy to cut the pieces with a large knife. I hit a problem with the final stage, I was certain that I had a jar of tartaric acid but when I went to get it I found that in fact it is cream of tartar. A little research told me that the cream of tartar isn't a substitute and since I don't have time to go out in search of the proper thing today I resorted to sugar with grated lemon zest. I will certainly order tartaric acid for the next batch.
The pâte tastes fine, I think another time I would want to reduce the sugar just a little, also the pectin if the latter can be reduced without losing setting capacity. Perhaps I scaled wrongly when adapting quantities given to account for the additional 40g purée.
As I said yesterday I should have followed the recipe to the letter and used a bread pan as a mould. I would then have produced cubes instead of slabs but I am quite happy with my first slabs!
Many thanks again to @gfron1 for the time taken to set out such an excellent guide for someone with limited home cooking skills, also to others who kindly gave advice about sourcing the right pectin.
I am well aware that I failed to produce equally sized pieces, more care needed next time!
