Does vacuum reduce the sugar content?

[PerryW]

Someone told me they thought that using a vacuum system would give you much more sap, but that the sugar percentage would be lower.

Is there any truth to that rumor?

I've been toying with the idea of vacuum for a few years now and I'm trying to weigh all my options.

[ennismaple]

I don't believe it reduces the sugar content. I'm sure there's been research done on this topic. Investing in a vacuum system is by far the best money you can spend on a maple syrup operation. Go ahead and git 'er done!

[DS Maple]

It is true that vacuum reduces sugar content. More sap moves out of the tree faster, and therefore does not have the normal amount of time to absorb/collect sugar. Buckets will generally be the sweetest because there is no vacuum at all, gravity lines will be second because there is a natural vacuum created, and sugar on artificial vac systems will be the lowest. Research has also proved though that increase in sap volume outweighs the decrease in sugar content, so vac systems are worth investing in. For example, by increasing the pressure differential between the tree and the lines by way of artificial vacuum, sap may run on days when it oridinarily would not under normal atmospheric conditions. In this case the sap may not be as sweet, but you are getting sap that you wouldn't ever see without the system.

[markcasper]

It usually runs .2-.3 lower in my observations. Such a miniscule amount you'd still be wrong in not investing in vacuum. The volume is in more cases at least double over natural vacuum.

[Gary R]

Here, check out this research.

http://www.uvm.edu/~pmrc/vacsap.pdf

[Russell Lampron]

Vacuum is one of the least expensive ways to get more sap. As long as you don't go crazy a vacuum system will pay for itself in the first season. The sap does tend to have a slightly lower sugar content but that's where the RO machine comes into the picture. Weak sap gets sweet pretty fast with one of those.

[PerryW]

I guess I have a few reservations about adding vacuum to my 650 tap sugarbush

1) I have 3/4" black plastic mainlines on 9 gauge wire with no more than 200 or so taps on each one, but the mainline is 20 years old. It would probably need replacing to get good vacuum (I'm assuming?)

2) Most of my lateral lines are the old non-rigid tubing, much of it I bought used and is 20+ years old. I have many lines with 20-25 taps; so I assume it must repiped. It is real steep, if that makes any difference. I guessing I would need to buy quit a few rolls of new tubing and new drops.

3) No electric power and the bush is 6 miles from the sugarhouse; so having to drive over each day and fill w/ gas and start the motor. Also I'm hesitant to have to have a noisy motor running that annoys the neighbors.

4) Seems like an off-the-shelf complete vacuum system would end up costing $4,000 or more! That would buy a lot of tubing & new taps, which would increase my production without buying a vacuum system. I suppose I could shop around and put together a system from odds & ends; but I'm more of a woodworker than a gearhead.

I dunno, my 100-120 gallons from my existing setup is a good amount to sell retail in my situation. My boils are rarely more than 4-5 hours and I have very few expenses. Using the same equipment for 20 years; my annual expenses are very low. Just gas, jugs, and a few repairs.

[Russell Lampron]

Perry,

If there are power lines going by your sugar bush you could build a pump house and have an electric service put in. Royalmaple did that and runs an electric vacuum pump and releaser.

Just as a comparison I have just over 600 taps this season. 83 of those are buckets which all but 6 are on sugar maples. I have about 550 on vacuum of which more than 400 are on red maples. I have made close to 120 gallons of syrup so far this season. That number would be higher too but I accidentally pumped 600 gallons of 2.2% sap onto the ground. My buckets gave up after last Thursdays run. I have collected more than 1100 gallons of sap from my vacuum taps since then and had close to 200 gallons of sap in the woods tank last night. The vacuum pump is still on.

As far as the lines and tubing are concerned it is time to replace it all anyway. If you retube it you will get more sap even if you stay gravity but will get much more on vacuum. If I were thinking of adding vacuum in a situation like yours I would retube the woods with vacuum in mind and run it gravity for a year if I couldn't afford to retube and get vacuum at the same time. The bulk syrup prices even though they have dropped for now are still pretty good and making more than what will satisfy your retail needs will pay for the new equipment pretty quick.

[PATheron]

Perry- You could always try a dairy pump and glass bowl releaser. Wouldnt cost much really and try your hand at it. I bet the way it is now it would work pretty good. Pretty cheap investment for the possable increase in sap. Theron

[PerryW]

Thanks for the help guys. There is power over there; I'll have to look into the costs of getting service.

What I really should do is build a sugarhouse over there; but it's convenient having the sugarhouse here at home too.

[Homestead Maple]

Perry,
Check with WhiteMt. Maple. He had an electric service installed at his sugar bush prior to this season so that he could run vacuum. His electric company is NH Electric CO-OP, which I'm guessing is who you have.

[white mt]

perryw the cost for electric at my bush was not high. the co.op gives you a $1800 of credit if you spend under that its free. yes free .You pay 250.00 to start new service and that 250.00 you get as a credit on your new bill.Build A small pump house and have the power hooked to that.If you are close to power lines you dont need to set a new pole.

[Jeff E]

Just wanting to highlight Gary R's post on the Proctor Research that says no significant/measurable sugar decline in sap due to vacuum.

[sapman]

If you can get power where you need it inexpensively, I'd go for it in an instant. Power company here wanted $3600 for the first pole, plus $1000 for each additional, and I really would have needed two or three to get close to where I wanted it. Hence, I'm doing gas, which is a pain to keep up and loud. Fortunately, the nearest neighbors are 1/4 mile away, so not very loud for them. But I'm getting sap while my buckets have quit, and my buddy's gravity system isn't doing anything.

Tim