I did a slow roast pork today putting pork knuckles on the bone cooking for 8 hours in a dash of apple juice.   After cooking, I left it to cool for an hour with the lid on.   When I lifted the lid, I noticed a 'lightness' to the smell of the pork, almost the lightness you might get when smelling a bouquet of flowers. (Sorry to those who feel this description is overdone - I'm trying to capture an idea in words).   It almost reminded me of the caramelisation of onion when cooked on a frying pan.   Help me out here - what is the term I'm looking for? Is it caramelisation?  My question is: What is the name for the 'sweetness' of cooling roast pork? 
IMHO, there is no single answer to this question. It largely depends on the way you are "chilling". It ranges from:   Leave the pot on the counter until cooled to room temp, then stick it into the fridge until cold. Could be anywhere in the range of 2-6 hours, I guess.   with a bunch of variations up to:   Transfer custard from hot pot into a flat, pre-chilled metal bowl or baking tray, plunge bottom into a salted ice bath (or pile of snow if it's freezing outside) and stir constantly with a rubber spatula. Should be cold within minutes.   So what would I do? I'd make the custard a day in advance, let it cool somewhat, then freeze the cubes over night. Never bother about the given 4 hours first freeze, because I assume this is a minimum time to get the cubes frozen fully. Finish the ice cream  4-5 hours before planned serving time the next day, because it might get too hard if frozen too long, but this depends on the recipe and I can't say for sure what the texture would be in this case. 