Airborne contaminants during boiling and syrup quality

[CarrieAndCraig]

This year we moved up to a 2x5 boiler and the boys set it on skids atop plywood instead of the recommended concrete. We started our first boil with it yesterday. Within the first 30 minutes the hot metal started to burn the plywood, which really stinks as the glues off-gased. Their solution, although well intended, was to put cement board between the plywood and base of the evaporator. That too started to react to the extreme heat, causing the styrofoam beads (polystyrene) and chemical binders in the cement board to melt and off-gas quite intensely. The off-gassing and melting continued for the 5 hour duration of the boil. My opinion is to err on the side of caution and dump the batch. The offensive material has been replaced with concrete. My question to the forum is this. To what degree do airborne contaminants, such as diesel fumes and burning polystyrene and other hazardous substances in the boiling environment affect the taste and, possibly health quality of the finished product?

[maple flats]

I can't answer that, but my gut feeling is that it needs to be dumped, then clean the pans completely and start fresh with no offensive issues. Just chock it up to an education that only cost some syrup and some elbow grease to remedy.

[CarrieAndCraig]

Agreed, I would have dumped it. My friends, however, feel I'm over reacting, so it's been bottled and taken to share with their family for easter. I can't do anything about that, other than hope there's no issues. If this was a business, I wouldn't take any chances with contamination in the sugar shack. However, since this is a hobby operation on my friend's property, I have no authority over what goes on. I've always had excellent maple syrup in the past. But this year when my friends have joined in the production, I don't have the control I'm used to. I'd rather not waste my time producing syrup that I'm not comfortable serving to my family, so I need some hard facts to argue my case, if there is one, about keeping the environment clean, if not sterile. Does anyone know, to what extent can the boiling sap absorb airborne contaminants? Can it become contaminated to the point where it could be hazardous to your health, depending on the nature of the pollutant?

[ecolbeck]

There are way too many variables to consider in this situation to be able to give you a definitive answer. Type of pollutant, solubility in water, airborne concentration in proximity to evaporator, exposure time, to name just a few. Syrup can certainly become “contaminated” with smoke and ash from the fire. I can attest to that from my early days. From what you describe I certainly would have dumped the batch,or at least stopped the boil and solved the problem.

Speaking of solving the problem, I wonder how the evaporator is producing so much uncontrolled waste heat that it is able to burn plywood and melt cement board. Are the grates open to the ground? Is it bricked and insulated?

[CarrieAndCraig]

Thank you ecolbeck. I agree, too many variables to know for my specific situation. I'm looking into having a sample of that batch tested, mainly out of curiosity. I'll put it this way, the off-gassing was so irritating to me that I couldn't be near the evaporator. My heart would race and my arms got weak and shaky when I was inhaling it. Did not smell nice like a sugar shack should.

20043Unlike my 2x3 evaporator, there is no sand or other type of insulation in this one. It is just lined with fire brick on the sides. Concrete patio slabs have since been installed between the evaporator and the plywood and seems to be okay now. After the season the plan is to remove the skids. Should there be sand along the bottom?