I originally used their spec, but have since learned milk punch is pretty forgiving. It works really well for complex flavors that have a lot of tannins or volatile constituents (tea, wine, citrus, etc). I’ve found good black tea and a deep, sweet port tends to be a winning combination.

Done correctly, the resulting punch is shelf stable. That said, it has a neat trick: since no filtration is perfect, you end up with trace amounts of milk fats in the solution that continue to react with any left over volatiles. This leads to a smoother, rounder flavor over time. The last batch I made with a bergamot tea and port ended up tasting like a fruity, complex boba tea after a couple months of rest.