Mold in syurp

[bigjohnsons]

I have been doing this for 4 years and have never had this problem.
This year I have 8 bottles with a slight film/mold on the syrup. I don't know if it is because the caps did not seal properly or was it just a bad batch etc? I made about 40 bottles in total this year and the rest were fine.

Question: Can I reboil filter and bottle or should I just throw it away. I do not sell it but I do give it to my kids and family.

It is a lot of time to make it and I would hate to throw away almost a gallon of syrup.

Thanks

[psparr]

Probably bad caps. Seems to be the norm this year.
You can skim it, reheat and bottle. Won't harm a thing.

[Run Forest Run!]

I'm doing the exact same thing right now - reheating a gallon after taking off a little mold. Doesn't happen all the time, but not a disaster if it does.

[bigjohnsons]

Thanks,

I use a coffee urn to bottle. Can I just pour it in, let the urn heat it to 180, skim and bottle or should I do any thing else?

[Run Forest Run!]

Skim off the mold first, then heat to bottling temperature. You're good to go after that. Make sure the bottles you are reusing are sterilized before you add the hot syrup, and use new lids (obviously). Good luck!

[psparr]

Preheat the urn first with a little water. The brew cycle temp is way too high and will cause niter to form. Should probably reheat on the stove at a low temp stirring constantly to avoid hot spots. Then pour in your preheated urn to bottle.

[lpakiz]

I was filling some glass gallons a couple days ago and I noticed something I have not seen mentioned concerning unexplained mold in your syrup.
While filling the jugs, I noticed condensation from the hot syrup collecting on the sides of the jug. As the syrup rose, it cleaned off that water and, I assume, the water rose gently with the level in the bottle. After the bottle is full, there is a good amount of seriously under-dense syrup collected at the top of the bottle. Laying the bottle on its side does tend to blend this syrup, but I noticed later, after I righted the bottles, that there was another bunch if condensation on the neck of the jug, where the syrup level had fallen after cooling. It's this under-dense syrup that might lead to mold. After the jugs cooled to a temp that didn't cause further condensation, I shook them up again, to ensure that all syrup was at proper density.
I suspect the issue gets more pronounced the cooler the bottle and bottling area is.
You folks that preheat your glass, please disregard.

[Clinkis]

May want to double check your density. If your syrup is a little light it is more prone to mold.

[maple flats]

This soon after the season I'd suspect low density syrup too. It's too soon and been too cold for mold in proper density syrup. If that's going to happen it generally takes a few months and warmer temperatures before you begin to see mold.

[Big_Eddy]

I agree with Maple Flats. Mould growing on syrup that has been in storage for several months is likely due to condensation under the cap, bottling too cold, or a bad seal on the bottle.

Mould growing on syrup within a few weeks is most likely due to under density syrup.

Skimming the mould off and reboiling the syrup is common practice, but more recent studies recommend disposal due to possible allergic reactions to certain mould spores.
https://onmaplesyrup.wordpress.com/2016/03/03/ontario-maple-syrup-production-report/