Color of syrup and judging where in season ?

[TerryEspo]

I am wondering if there is any science behind the color of syrup and it signaling where we are in our season.

Seems that first sap runs give us light fancy syrup, Amber comes next and dark comes late season.

I ask because I am still making light-amber, no dark amber, nothing even near dark yet. Does that mean that I am maybe halfway through my season?

Does syrup color tell us anything?

[saphound]

I don't know the science behind it, but my last batch was the darkest syrup I've ever made and I think it's about over in my area..not getting much sap at all now. I would go by your own observations since 2011. Has your syrup darkened at the end in years past? If it has, I'd say you have a ways to go. Seems like it was a late start up there this year, but everyone now is saying there's a sap tsunami. Keep an eye on the buds...but sounds like you have a ways to go tho. ;)

[Russell Lampron]

Generally the syrup gets darker as the season progresses. That isn't always the case though. I have had seasons where I started out making dark syrup and ended the season making light syrup. The only way to know that the season is done is when you stop getting sap weather or when the trees bud.

[DrTimPerkins]

I am wondering if there is any science behind the color of syrup and it signaling where we are in our season.

Yes, there is an amazing amount of science related to sap to syrup chemistry and flavor/color development. From such a seemingly simple solution (predominantly water and sugar), there ends up being over 100 distinct flavor molecules in maple syrup, and most of those form from either Maillard reactions or caramelization processes, both of which are very complex.

The simplified version is that the color of the syrup is largely dictated by the quantity and activity of micro-organisms in the sap converting some (a surprising small %) of the sucrose into invert sugars (fructose and glucose). Invert sugars tend to caramelize (form color and flavor) at much higher rates than sucrose, and are also more active in Maillard reactions in combination with amino and organic acids in the sap. So it is largely temperature and cleanliness of the sap collection/filtering system, along with the length of time the sap is stored prior to processing that dictates the color/flavor profile. Sap collected when it is warmer, or if stored for a period of time, will have more microbes, higher invert levels, and end up being darker with a stronger flavor. So when starting the season, with it being cold and everything being very clean, you get a very light syrup. As the season goes on and it warms up, you transition to an amber and then a dark. At the end when it is very warm and the microbes are well established, you make a very dark or commercial syrup. Of course the weather doesn't always follow that cold-warm-hot pattern, so we can see some movement towards lighter then darker then ligher syrup during the course of the season, but the general pattern is typically from light to dark to very dark.

At the end of the season there can occasionally be other things going on that cause unusual things to happen. If the sap gets really fermented, the pH can be very low such that during boiling it never goes above pH 7, thus never enters the "alkaline degradation" phase, which is a time when color/flavor is turbo-charged. Since it never reaches that point, you can sometimes end up with a really light syrup (with a fairly crappy fermented flavor) at the end of the season.

As far as syrup color being an indicator of time of season.....VERY roughly perhaps.