Dark syrup

[H'Artwind]

Does anyone know the myriad of reasons (and why) for getting dark ("robust" haha) syrup? A couple of buckets had been cloudy but that was before the 32+ temps so I knew it hadn't spoiled. I understand that temps above 45 will produce a darker syrup as well as later-in-the-season sap. Anyone know the 'mechanism' behind the darkness? Are there more minerals in it? Has the sugar 'broken down'? Thanks for any and all info!

[MichtonTree]

From what I have read, rising temperatures warm trees as the season progresses, and nutrients that promote bud and leaf growth increase and darken the syrup.

[Ausable]

When I would batch boil - my syrup was a lot lighter that it is now. I have a homemade - steel - continuous flow rig and I leave the pans sweet and pick-up where I left off on my previous boil and my syrup is much darker than it was in the batch pan. Gosh - I think a whole lot of things enter into it - As Michton already said, Sitting in steel pans, Number of times brought to a boil - for just a few. I'm sure others will chime in and give several other causes for darker maple syrup.