I think a lot of folks use a sugar solution and a Calpol dosing syringe, never tried it but sounds like a good method. If you've access to a 3d printer it's easy enough to print scoops of different sizes, a printed funnel made for the shape of the bottle neck comes in very useful here too. (ABS is suitable for food grade but I soak them in steriliser for a while because stuff can get stuck in the gaps left by 3d printing).