Fresh sap- Different colours, tastes great ?? [Archive]

TerryEspo

03-07-2013, 08:28 PM

Second guessing myslef now after just reading another post about old sap, discolored and stuff.

I have been getting slow sap drips for the last two days. Some of my sap is clear as spring water, but other buckets have a yellow tinge, like a bit of Mountain Dew was added.

Excited to taste sap, I have been drinking it right from the pails, all of it tasted fine, sweetish, no matter what color.

Why is not all sap the same color? This is not old sap and frozen at night.

Can anyone explain this to me?

Thanks.

Terry

timmeh87

03-08-2013, 12:45 PM

I was collecting sap in white buckets today and thinking about this question... I think it is both colors depending on how you look at it (literally how you view the sap with your eyes)

Part 1 of my theory is that the sap has a faint yellow hue, like syrup. This could mean that molecules in the syrup reflect only yellow light, or it could mean that absorb mostly blue light or both. Lets assume that they only reflect yellow light. If white light were to pass through a very faintly colored solution, it may have the effect of filtering the yellow out of the white light, causing the ray of white light to turn blue as it passes through. Usually deeply colored liquids will color light the same color as the liquid, so I cant exactly account for why the complementary color does not always come out.. My theory says that they are colored with substances that only absorb light, so the complementary color is absorbed.

Part 2 says that sap is slightly fluorescent, so that it glows blue when the sun hits it. This is a known effect

(link does not work?? google "Assessment of maple syrup physico-chemistry and typicity by means of fluorescence spectroscopy ")

" and the second one at 460nm, excited at 360 (syrup) or 370nm (sap)"

So that is a blue peak caused by Ultraviolet A (near UV) light

This article suggests that the fluorescence changes as the season progresses.