Funny sap question

[konwinski]

Hey there everybody. I have a question. I had a bit of sap seem to go bad this week because I didn't have time to boil during the week. I went around and collected sap today and I think it may be suspect as well. When the sap is getting up to boiling it seems to get a milky film over it. It doesn't boil away either. I am concerned that I may be wasting my time cooking it. Any insight will be greatly appreciated.

Thanks,
Ken

[Sugarmaker]

Ken,
How does it smell and taste? If the trees you tap are hard maple then the sap just jot too warm. Think of sap like milk. We dont let our milk set out of the fridge for days, same with sap. Try to gather and boil or store in a cool place until you can boil. If the sap is cloudy and or has some color to it then it may still be ok and make dark syrup. If you dont like it dump it and clean things up and start with some fresher sap from this next run. If it was me I would continue to boil it and see what the taste is as it gets close to syrup. How much of this are you boiling down?
Regards,
Chris

[happy thoughts]

That sounds like normal scum that forms on heating. Skim it off and discard it.

[konwinski]

I dumped the bad stuff and I am going to boil the new and see how it goes, I have about 25 gallons, just a backyard guy.

[DoubleBrookMaple]

Hi Ken,

My experience for what it is worth.
I am no expert, but last year was my first year and I did research on sap storage and remember reading that sap will keep for about a week if stored below near or below 40. Bacteria count will go up, and should not be a great problem, but the proof is in the syrup. I tapped my first tree last year on March 24th and did my first boil on April 2nd. (Funny.. the same as this year!) The boil was 9 days after first collection, but it was stored in barrels packed in snow, so very cold. The syrup was good, Grade B, nearly dark amber.
I cannot comment on the "milky film", with certainty. I think hi bacteria can sometimes cause Grade B if I remember correctly, but not sure. I think you should just boil it off, and see what you get. The boiling will kill all bacteria, so I would not fret.

Now that I read your post again, I see that the "milky film" was during boiling. I get some of that on fresh sap. not a lot, but I was skimming some off this year. Mine was more of a white foam, with some brown in it. Maybe someone with more experience will comment.

[Sugarmaker]

Ken,
Yes that is a option. But it may have made syrup that was OK only darker. Standing over your pan and tasting and smelling are about the best indicators of the potential syrup quality. If the grade is dark but good flavor its still good on your pancakes! And if dark and/or not good flavor you can send it to your local bulk syrup buyer and it still may be worth $22 per gallon.
Regards,
Chris

[konwinski]

It should be fine. I just get concerned with "spoiled things" But for the time that it is boiling it should/will kill anything in it.