Good sap and bad sap

[mainebackswoodssyrup]

Got a call from a friend yesterday asking if I could explain why he had some good, clear sap on his 3/16" lines and very cloudy sap on his 5/16" gravity lines. 3/16" lines and taps are new this year. 5/16" lines are 3-4 years old but drops and taps are 2 years old or less. Sugar on the 3/16" tested 2.2%, not sure about 5/16". All trees are very good producing sugar maples, not 1 red mixed in anywhere. 320 taps or so all in the same area, same sun, etc.

Anyway, I had no clue but am curious if others might be able to explain.

[maple flats]

One reason could be the way sap flows in each, on 3/16 the sap flows without ever having the gasses pas over and leave sap setting in a low spot, on 5/16 you must have a slope down hill on every spot in the line, low spots collect sap that can then get warmed too much by the sun and begin to spoil.
Then in the end, both will still make good syrup, but the clear one will tend to make a lighter syrup than the cloudy one and the cloudy one will often be a lower sugar % than what it was when it came from the tree. The age of the tubing can also be a factor, especially if it was not cleaned after the past seasons.

[NhShaun]

There are a lot of variables there. Could be something to do with the older tubing on the 5/16 with old drops and taps. Some bacteria was surely sent into the collection tank on from the older lines, then hangs out there all season(assuming you don't clean your collection tank at that line every week) plus the warmer temps might accelerate the whole scenario. Just my thoughts.

[Sugarmaker]

My guess would be more chance for air and bacteria growth in the 5/16. But the cloudy sap may make good syrup. just darker.
Regards,
Chris

[DrTimPerkins]

3/16" lines and taps are new this year. 5/16" lines are 3-4 years old but drops and taps are 2 years old or less.

There is your answer. Microbial contamination increases in tubing as it ages, which results in more sap degradation and lower sap yields. It is all related.

http://www.uvm.edu/~pmrc/aging.pdf
http://www.uvm.edu/~pmrc/tubing_age.pdf

[Sugarmaker]

Dr. Tim,
So my 5/16 tubing is 8 plus years old. The drops and taps have been changed several times. Is it time to replace the whole system? These are short run tubing systems, 5/16 is the main line 12 to 24 taps per line. I have been rinsing the systems with water each year and have done pretty well on normal sap volumes. This year not so good, but not many folks are up to a normal crop. I am cheap and don't really want to spend the money and or time to rebuild the entire system. But maybe its time???:)
Sorry to hijack the thread.
Regards,
Chris

[mainebackswoodssyrup]

No problem Chris, good place to ask. Makes sense it is probably stuff in the tubing. I just didn’t think 4 year old tubing would be that much different than new. Guess so.

[DrTimPerkins]

We have some 5/16" lateral line tubing (various manufacturers) in our woods that is now 14 yrs old. Almost all our syrup this year is Golden-Delicate. The tubing is still good as long as it isn't getting brittle (some varieties of tubing) and the fittings aren't pulling off. As long as you are practicing good spout/drop sanitation, there is little reason to change tubing (in terms of sap yield) until it has reached the end of its rated lifetime. Often you can exceed that without problems. Sap quality is related to many things, but if you're not cleaning your tubing with some type of sanitizer each year (and depending on the sanitizer, rinsing or letting first sap run on the ground -- water is not a sanitizer), you probably aren't going to see any improvement there except for one year after retubing.

[Sugarmaker]

Dr. Tim
I was probably sleeping during this discussion? What is your recommended sanitizer? And methods of cleaning?
Regards,
Chris