Hanna Checker

[abbott]

Ok, so I just had a long conversation with Matt at Hanna Instruments who was involved in the development of the Syrup Tester. Lets see how much of this I can get written while I remember.

Maple syrup should be graded using a path length of 10mm through a square cuvette using light at 560 nm wavelength. As compared to a glycerol sample. This according to USDA standards, which can be found here: https://www.ams.usda.gov/sites/defau...pStandards.pdf

The Hanna tester uses a cylindrical cuvette with a longer path length, so the actual light transmittance detected is converted to account for the differences before the result is displayed on the screen. In other words, the actual light transmittance as seen through a VT temp. kit is way lower than the grading standards since you are looking through a couple centimeters of syrup rather than 10mm. But the samples in the kit are also calibrated accordingly. Hanna doesn't include all of this on their instruction manual to keep it simple.

The Hanna folks tried calibrating with water, but found that water was too temperature sensitive. They do not recommend opening and testing the VT temp kit as the matrix of the sample would differ and not necessarily provide results corresponding to a visual interpretation. I'll probably do it anyway, because why not? The kit is useless after the season anyway.

The kits only have 4% accuracy... so that's basically the room you have to make a judgement call on what grade to call a borderline sample.

We concluded that the reddish tint found in my syrup was likely causing me to interpret the color as being darker than it actually is... possibly combining with a Vt temp sample that is somewhat lighter than it should be.

As a bit of a side note, I have heard some folks say that you need to take flavor into account under the new grading system. After reading the USDA standards, that does not appear to be the case. It clearly states, "The color class of maple syrup is determined by... (t)he percent of light transmission through the syrup..." However, it is also notes that in order to be grade A, the syrup must "(Possess) a good maple flavor (taste) characteristic of the color."

Even using the Hanna meter (with its 4% accuracy) there is enough of a fudge factor that I will plan on using flavor to grade borderline lots.

Hope someone finds this helpful! If I get a chance to take some good pictures of my samples I'll post them.

[markcasper]

If these are only 4% accurate, why would anyone buy one??

[wiam]

If these are only 4% accurate, why would anyone buy one??

They are within 4% light transmission. Not 4% accurate.

[markcasper]

The kits only have 4% accuracy... so that's basically the room you have to make a judgement call on what grade to call a borderline sample.

I guess one of us, or both, misunderstood.

Would one buy this one, or the 350 plus dollar permanent ones? Will the USDA be coming out with a permanent grade set like my old one?? This is what sucks,the IMSI, the government tells us this is the way its going to be, will be prosecuted if its misgraded, but leaves us in the dark without a grader or an approved one, unaffordable as well.

[NH Maplemaker]

I used the checker all last season and when the maple inspector came in the spring she said everything checked out good! She then asked me How I graded the syrup? I told her that this year I used the checker ! She replied that her boss had order bunch of them for all the inspectors but they hadn't arrived them yet ! she asked if she could look at it as she had never seen one. She did a few comparisons with it using her equipment and the checker and when she was done said "this is great, can't wait to get one everything fell with in the grades just fine" I didn't tell her that we had also double checked everything with the new USDA permanent grade set!
So if New Hampshire maple inspectors are going to use them as one of there tools, Then it's good for me !

[markcasper]

I didn't tell her that we had also double checked everything with the new USDA permanent grade set!
So if New Hampshire maple inspectors are going to use them as one of there tools, Then it's good for me !

Let me get this straight......the USDA has a new permanent set with the new grade names? Where do I find out about this? As mentioned before, WIS. now has decided that grading be mandatory, but they have failed to tell us what we should use to grade, or what type or style is allowed. For Hanna to come out and manufacture a grader without having government approval was a huge risk on their part IMO.

[NH Maplemaker]

Ok, let me back- up a little bit! what I doubled checked with is the Lovibond Grading Comparator that has the new USDA international standard wheel ! I believe your right, USDA hasn't come out with a permanent grade set as of yet! Lovibond is what Leader and Bascoms are selling! Yes, they are not cheap $325.00 plus shipping!

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[markcasper]

Ok, let me back- up a little bit! what I doubled checked with is the Lovibond Grading Comparator that has the new USDA international standard wheel ! I believe your right, USDA hasn't come out with a permanent grade set as of yet! Lovibond is what Leader and Bascoms are selling! Yes, they are not cheap $325.00 plus shipping!

Have you heard whether the USDA will be manufacturing their own??? I would go with a Hanna, but during the season when things get messy an old time USDA comparer would seem to be the best choice and the fastest and easiest. The hanna would work good if you have a labratory, but having to have it completely cleaned for it to be accurate kind of scares me, along with keeping hard water spots and scratches off it. Since this is international, maybe Canada will be coming out with one?

[DrTimPerkins]

Have you heard whether the USDA will be manufacturing their own???

I believe that the last time someone from UVM PMRC spoke with them (over a year ago), it was not on their list for the short-term future. Perhaps we can check with them again. The options are temporary kits (both Vermont and Quebec make them) -- cheap, but you should get a new one each year, electronic graders -- moderate in price, but have to take some care in using them, or permanent grading kits (Lovibond) -- very expensive.

[maple flats]

I use the Hanna and like it. I use distilled water to clean the cuvettes, but I have now ordered 25 new cuvettes so I will use a new clean one on each test, I just wipe the outside with a micro fiber cloth, then remove the cap and fill the cuvette to the fill line.
I use serial numbered labels on my containers and a log book which shows each batch and the Hanna meter result. While I haven't had any customers ask for specific darkness within a grade, I can get that info if requested simply by checking the serial number and checking in the log book. I won't be taking the time to display it on each container unless I start getting a few customers who ask.