Whenever I fall into a conversation about pork pies (obsessed, me?) someone will eventually say "The jelly sounds scary" or "I don't understand gelatine". At which point I want to clutch them to my bosom in sympathy. My first few pork pie attempts, I just couldn't do the jelly. Sad things, they were - just a ball of seasoned pork roughly encased in pastry, the one coming apart from each other, underlining the basic uselessness of actually making a pork pie rather than buying one.
I couldn't do the jelly because I didn't understand what was going on. What do you mean boil up a pig's trotter? Calves' foot what? The alternative, to set some run-of-the-mill stock with gelatine seemed similarly alientating. How much? Which gelatine? Powdered, leaf? Argh! Can I pour the leftovers down the sink or will it clog up the plumbing for all of north London? The whole thing sent me screaming to re-read The Pedant in the Kitchen for absolution.
But, I've sorted a few things out for myself in my head about jellies and gelatine. So, for anyone who remains confused about the matter, here's my beginner's guide to gelatine use. This will be, to a lot of people, bleeding obvious and I don't, would never, claim to be an expert - this is just something I wish I'd read a few months ago.
Boiling bones to get jelly.
The reason that you boil up pig's trotters or veal bones is that they naturally contain gelatine. Pig trotter or veal stock, when cold, is jelly-like; when it is hot, it is liquid. It's amazing - you have to see it to believe it, but that's what happens. So when you're making a pork pie, the gold standard is to make a stock out of either a trotter or veal bones (but not chicken, because it doesn't contain enough gelatine), with vegetables and all sorts of delicious stuff in it. Once it's made you warm it up so that it's runny enough to get through the hole in the top of your pie and then when it's cool, it sets round the pork. Bingo.
Using gelatine to set stock
The trouble with gelatine is that the packets are so not user-friendly. They say things like "This packet will set 1.5 litres of liquid" - but I don't want 1.5 litres! - or "To set hot liquid, stir slowly into the mixture when it is cold, then heat gently, let cool, leave to stand and remove" or "One leaf of gelatine is equivalent to two teaspoons of powdered gelatine" - which will set HOW MUCH LIQUID? For someone who is useless at those "If it takes one man six hours to dig a hole" blah blah questions, this all drove me quite potty. But then I found a powdered gelatine by Dr Oetker, the instructions for which were, thank God, written for dimwits like me. One 30g sachet of powdered gelatine sets one pint of liquid. Finally. Thank god. I make pretty small pies, so I use only half a pint of stock, which is half a 30g sachet, which is 15g.
Like all things good and holy, Dr Oetker's beef gelatine is available at Waitrose.