sap refractor or sap hydrometer

[ash10383]

Husband built a RO last week for our 50 taps so now I'm looking at getting a testing device for the permeate...either a sap hydrometer or sap refractometer...is there a significant difference in accuracy between the two? a tall sap hydrometer is $30 from Leader and a 0-10% refractometer is about the same on Amazon....
TIA!

[old fashioned]

I have used a hydrometer for 35 years. It is a simple reliable method. Based on your method - I'm a flat pan - you may have to take off before the test line because the syrup will continue to evaporate while cooling.

[Russell Lampron]

You may not be concentrating that high yet but get a refractometer that will read up to 32% so that you can test your concentrate too. I like to know how sweet my "sweet" is before I send it to the head tank and I concentrate to 12% to 14%. It is about the same price as the 0% to 10% version. When you factor in the cost of the test cup and hydrometer the refractometer is less expensive and will remain accurate for years.

The best way to test your permeate is to boil some down to concentrate the sugar if there is any.

[SeanD]

I have both and I much prefer the refractometer. Just a few drops are needed and you get an accurate reading right away. I test so many times that it would be a pain to be constantly filling the cup and cleaning the cup and hydrometer after. For the refractometer, you just have to clean a small lens and you are good to go for the next test. Be sure to get one that says ATC. That means Automatic Temperature Correction. That way what you read is what you have for sugar and you don't have to use a thermometer and a conversion table - another advantage over the hydrometer.

Sean

[BreezyHill]

Been in the game for over 45 years now and dad bought the first RO in 1982, only had a refractrometer for the last 3 years. The Hdrometer is in the glass display with the bucket spouts and the spouts from lamb. LOL

When you rinse and ro there will be a period of time that you will be flushing out sugar levels the same as your permeate. Then it will slowly decrease to Zero. I have captured as much as 55 gallons of flush before I got a reading of under .5%. That captured sap test 7.6% after running at 14% concentrate. That's a nice amount of syrup that would had been going down the drain for years.

I get over the years since the RO we have put as much sugar down the drain as we had made those first couple years on small rigs.

I got mine on ebay for less than $11. Works great!!!

For syrup I still like the hydr as I can keep drawing into the cup and pour into the rig if to low or the batch tank if it is at line.

The post on pull early is one way or draw a little long to keep the batch density correct.

[Russell Lampron]

When you rinse and ro there will be a period of time that you will be flushing out sugar levels the same as your permeate. Then it will slowly decrease to Zero. I have captured as much as 55 gallons of flush before I got a reading of under .5%. That captured sap test 7.6% after running at 14% concentrate. That's a nice amount of syrup that would had been going down the drain for years

Does this mean that you weren't doing a sugar flush after you were done concentrating and before you did your wash?

[blurr95]

So what is a decent refractometer for a hobbiest. Don't really want to spend a lot of money.

Jason

[Russell Lampron]

So what is a decent refractometer for a hobbiest. Don't really want to spend a lot of money.

Jason

Check Amazon and ebay. The brand isn't important as they all work the same and are pretty simple. Get one that has ATC so that it automatically compensates or the sap temperature. They are less expensive than a sap hydrometer and test cup.

[old fashioned]

Who says you don't learn something every day. I was the first reply to this post. After reading all the other responses, I'm going to look into a refractometer. Thanks for the education.

[wobbletop]

I have one of those 0-10% refractometers. It's the kind with ATC. I just bring a bit of sap with me into the house when I've collected for the day just to see the average brix.

I seem to have to calibrate the meter every day though. I use some of my RO (reverse osmosis) water to zero the scale before checking the sap. Not sure why it doesn't seem to keep zeroed from day to day, but if I zero it, my sap is consistently 2.0-2.3%. I also use it to check my cheap little RO system to see how well it's working.

This is like the one I got...
https://www.amazon.com/0-10-ATC-BRIX-REFRACTOMETER-Coolant/dp/B013S2CPAE

Oh, and you should get a TDS meter for your RO to make sure it's working and the membrane isn't passing more than it should.

And one final thing... If you're measuring sap, I would get the 0-10% refractometer instead of the 0-60% (or whatever). It will show the small changes in brix much easier.

[BreezyHill]

Not to the extent that we do now.

The old way was to run 30 gallons thru the 2 post 4" x 40" unit. Now it is all up to what the refractometer says.

If we run 100 gallons of perm thru the unit that's fine by me the first bit goes to the head tank and the rest goes into the batch tank.

I don't wash as often as most. The DOW Techs have spent a bunch of time with me to get the most out of these xle membranes and on of them was s fascinated with the use of the membrane in reverse of how it is normally used...not for purification of water for use but to keep what is normal cast away for production.

Washing a membrane after every or even every other day will shorten the life span. They recommending doing a flush and then test. If test is less than 95% then wash. I often can go 4 days between a wash.

And washing...well my unit has been setup all wrong for proper washing. You should be washing thru each post parallel to the rest. Series will cause the debris from post one to lay into post #2.

Next season we will have a new stainless cart built for 4 posts to run 2 pairs parallel to get the most out of our pump system in our unit. Cleaning with require the changing of a few threeway valves to set the posts to all parallel so that the flush, rinse, and subsequent washing will be done with all 4 posts parallel.

For best results each post will have a 1/8" needle valve to catch wash water to test the ph before and after each post to check the status of each membrane with a digital ph meter from ebay for far less than the ph strips we had been using prior to second half of last season.

Like the one post said, Thanks for the education. We all need to be educating ourselves so we can do a better job every season so we can get one step closer to profitability or more efficient production. Otherwise we will be two steps behind our neighbors.

Even the hobby maple nut needs to get every penny out of each dollar invested. This maple nut needs to get the most from every tree on the farm since the school and property taxes never go down.

Good Luck guys in the end of your season. In 1982 we were all washed and pulled the 15th of March.

[BreezyHill]

Have to agree to a point with Wobbletop.

Check the unit daily but I use a single bottle of bottle water. I found my RO was passing sugar to a small extent this way. She need adjustment and then I checked the resuts with a hydrometer I keep for checking the bottled water.

I use a 0-25% that has .2% gradient. the 0-82 are tough to read in the sugar house when I tried one.

I stick ours in the stream of sap and wash it off in the permeate flow each time. The cloth will get sugar rich and mess up your readings.

Great point wobbletop!

[concord maple]

I see the ATC units are for a minimum temperature of 10C or 50F. Are there charts for compensation if the sap is say 45F or 40F?

[ash10383]

got a home brew refractometer from amazon that goes to 32 brix for $30ish...like checking the sap before and after the RO but should have gotten the one that goes higher as now we have a blind area from 32-55 brix when finishing in the house before the hydrometer starts floating