I haven't tried Blueberry infusions yet, but have done a bit of reading into it and talking with local sugar makers.
It seems like some people just add blueberry extract, which would mean your syrup density would need to be adjusted? I imagine you can over flavor that pretty easily as the extract is pretty potent stuff.
Others seem to just drop a couple fresh blueberries into a bottle and hot pack it. I am not sure how much blueberry flavor is released from a whole blueberries or how they keep over time. I am also not sure how that fits into the bottling guidelines and labeling requirements as it is no longer pure syrup, especially visually.
And other people crush up some fresh blueberries and hot pack a large batch of syrup and let it age for a few weeks to a month. Then strain out, filter it and hot pack into smaller containers as usual. This method sounds like the most authentic
way to infuse and make sure you still have a clean looking syrup. It also seems easier to adjust things to find the flavor you are looking for. Sourcing local blueberries seems easier than finding blueberry extract as well.
I have just done the last method separately with cinnamon and vanilla beans and it turned out great! Running it all through my filter press and it came out crystal clear. I have had about 10 people taste test the samples and so far everyone likes it.
6th season solo sugar maker in a young sugar bush of mostly red maples
320 taps
2x6 self built arch, Flat pans w/ dividers
New 12x16 sugar house
CDL hobby 250 RO