I want to preserve my windowsill herbs before the plants die back, and my idea is to make herbal syrups for lemonades or cocktails. (Possibly even meat sauces.) The method I'll use is a cold, dry maceration - bruising herbs in sugar and leaving them in the fridge for a day or two for the sugar to absorb the flavour, and only using enough heat to dissolve the sugar later.
While this makes for superior flavour, the lack of boiling makes this prone to spoiling - my previous batches had weird gunk floating in them eventually.
I've read in other questions that freezing herbs alone can diminish their flavours. Can I, say freeze 1:1 or 2:1 syrup without this happening as well? Or maybe just freeze the sugar-herb mush once it's done macerating? (I'm hoping the flavours being bound in the sugar might help.)