Ultraviolet Light

[the old guy]

How Many Of You Guys Run Your Sap Through An Ultraviolet Light? I Try To Keep Sap Temp At Around 40-45, But If I Hold It More Than 48 Hrs, Syrup Darkens. Is Uv Light The Answer?

The Old Guy

[Homestead Maple]

I had one that I used for a number of years before I bought an RO and the light always helped me keep the grade for 24 hrs anyway. I would have meetings some nights and couldn't boil in what I collected that day, so I would have to wait until the following night. The light really helped when the temps the next day after gathering some would say be in the high 40's or more. I think they're a good investment for people that have to keep sap for a few days. There's plenty of research that has been done by the Proctor Research Center that I'm sure you could get access to on line that covers the use of the lights. I bought mine through a pet store and saved a lot. There used by some people for large fish tanks to keep the bacteria down.

[powerdub]

I think they are a must if you have an RO machine. I have no experience otherwise.

[the old guy]

It Seems To Me That At Some Point, An Ro Machine Is Desireable Over The Ultraviolet Light If You Have ??? Taps. Which Is The Better Option Then, For Let's Say 300 Taps--ro-or Ultraviolet Light?

[Brent]

Earlier this season I was on the forum about both RO and UV. Elected to go with RO. An experimental low cost one.

The way I see it a UV will do nothing for the RO processing, except buy storage time until you get to boil.

With the RO you
1) reduce the size of storage tanks
2) reduce boiling time
3) reduce fuel consumed


I suspect I'll end up with a UV too, sooner or later so that, at least on days of weak runs, I'll be able to postpone boiling and go to my day job.

[sapman]

Scott,

Just wondering why you say UV is a must with an RO? In my case, sap will be processed my the RO immediately, then boiled quickly, so I don't think there will really be enough time for bacteria to multiply too much.

Thanks,

Tim

[powerdub]

Tim, I may have made an overstatement about it being a must. Don't forget that you concentrate the bacteria as well as the sap so you all of a sudden have given the them a much richer feeding ground. You have turned sap storage from what could have been day into just hours. My concentrate may sit for ten hours before it is all boiled so it is a must for me. Let me add that correction to my post. I feel it is a must for me. Thanks Tim

[sapman]

Thanks, Scott. That does make a lot of sense if you have to store it. What kind of UV do you use? I've been told that another aspect of concentrate is that with the increase in sugar molecules, regular UVs can't really penetrate appreciably enough to kill the bacteria effectively. Therefore I opted not to plumb mine back in to the system. That said, I certainly would have if I had to hold the sap, RO'd or not!

Thanks and best regards,
Tim

[powerdub]

I will have to get back to you on what kind. It is an inline unit taken from a lab RO set up. The UV light is in a tube and the sap flow through it. It does work though. The non-scientific data I have collected over the years have proven that.

[Brent]

I really wanted to put a UV in this year, but the new evap, RO, plumbing, etc etc blew the budget.

Putting together a lot of comments from here and other places, you can likely us a unit from just about any manufacturer. But the key is how much exposure does the sap get. This depends on several design factors.
Flow rate in GPH and light Wattage.

You need substantially more exposure to the UV than for standard drinking water because the UV can't penetrate the sap as deep as clear water. If you go on the manufacturer's web sites you'll see a 12 GPH unit at $400 and another with the same GPH rating for $800 but the more expensive one has a more powerful bulb and an NSF (National Sanitation Foundation ) approval.

You get what you pay for. I would not buy the lower cost one in any GPH rating because of the turbidity of the sap. You gotta penetrate to sterilize.

[the old guy]

Hey Brent

Tell Me More About The "merlin Ro" That Might Work. I Checked On-line And The Cost Of A New Merlin Is About $365. That Is Affordable If It Does Indeed Work. I Get The Impression That It Is Tankless And Am Wondering How It Might Work???? The price, is that close ($365). All the RO's I've seen are between
$5,000 & $10,000.

The Old Guy

[Brent]

If you look under the RO section you can see where I first speculated on performance, then later tested in the kitchen with tap water.

Hopefully within a day or two ( or three ) I'll be up and boiling and then the RO will get the real test.

More to come.