can temp changes affect bottled syrup?

[canaanmaple]

Odd ball question here, but I like to always keep a stash of syrup bottles in the car for easy sales when out an about because the opportunity can present itself at any time. Now that it's summer, the temp in the car goes up and down quite a bit, and I am wondering if that can actually affect the quality of the syrup going from warm to cool over and over?

[ennismaple]

Yes it will. Fluctuations from hot to cold cause evaporation and condensation in the air space in the neck of the bottle resulting in a thin layer of diluted syrup on the top of the liquid. This will mould depending on how long it's in your car. The one thing that works too your advantage is being in the car will shake the bottles around and counteract that dilution of the syrup.

[canaanmaple]

not sure that makes sense to me? How can it evaporate if its sealed, and how could mold form if it's been bottled properly? I can see condensation happening though I guess.

[ennismaple]

In the same way that water evaporates off a lake or wet grass as the day warms up you'll get some evaporation from the top of the syrup in the headspace of a sealed bottle if stored in a warm car. When that bottle cools off some of the water vapour in the headspace condenses and creates a thin layer of sugary water on the top of the syrup - which is what moulds.

I do the same as you and always have bottles of syrup in the truck in the spring. Once it starts getting hotter in late spring I stop keeping it in the truck but will throw some bottles in for a day when I know I'm going to be around a group of people who may want syrup.