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Maple dabbler
02-22-2024, 08:39 PM
I'm just a hobbyist right now collecting syrup from 4 trees at home, and I don't have some basic equipment such as a hydrometer. The standard recommendation for hobbyists who don't have a hydrometer seems to be to just boil sap to 9 degrees F above boiling, but this has proven to be very inaccurate- the syrup I'm getting is too thin. It's difficult to just go by feel because you don't know the true viscosity of your syrup until it's also cooled down, and you don't want to cool it until it's bottled.

Even the float hydrometers I've used aren't very accurate because of the syrup's viscosity causing the bulb to not quite hit the equilibrium spot.

I am trying to figure out how to measure density with a standard kitchen scale. I don't see why this wouldn't be at least as accurate as a basic hydrometer. The problem is that literally no one seems to do this- it's always measured in brix, which doesn't have a direct conversion to density. The density values I've found online for maple syrup vary from a specific gravity of 1.32 to 1.37 and don't include the temperature. That's only a 4% difference but I am worried it might be enough to be the difference between syrup that crystalizes and syrup that doesn't, or syrup that could spoil and syrup that won't.

It's just surprising to me that this isn't a common way to finish syrup.

ScottT
02-22-2024, 09:05 PM
What kind of scale are you using that measures density?

johnallin
02-22-2024, 09:34 PM
I'm just a hobbyist right now collecting syrup from 4 trees at home, and I don't have some basic equipment such as a hydrometer. The standard recommendation for hobbyists who don't have a hydrometer seems to be to just boil sap to 9 degrees F above boiling, but this has proven to be very inaccurate- the syrup I'm getting is too thin. It's difficult to just go by feel because you don't know the true viscosity of your syrup until it's also cooled down, and you don't want to cool it until it's bottled.

Even the float hydrometers I've used aren't very accurate because of the syrup's viscosity causing the bulb to not quite hit the equilibrium spot.

I am trying to figure out how to measure density with a standard kitchen scale. I don't see why this wouldn't be at least as accurate as a basic hydrometer. The problem is that literally no one seems to do this- it's always measured in brix, which doesn't have a direct conversion to density. The density values I've found online for maple syrup vary from a specific gravity of 1.32 to 1.37 and don't include the temperature. That's only a 4% difference but I am worried it might be enough to be the difference between syrup that crystalizes and syrup that doesn't, or syrup that could spoil and syrup that won't.

It's just surprising to me that this isn't a common way to finish syrup.

There is a common way to finish syrup... a Hydrometer with known temp of the sample and you're done.

Maple dabbler
02-23-2024, 12:02 AM
What kind of scale are you using that measures density?

Density is mass divided by volume...

Volume is easy to measure. You can calibrate pretty much any narrow container with water, since its specific gravity is exactly 1.

Maple dabbler
02-23-2024, 12:07 AM
There is a common way to finish syrup... a Hydrometer with known temp of the sample and you're done.

What if I want to use the tools I have right now because I am finishing syrup right now and don't want to wait for a hydrometer to get delivered, like I said in my post?

johnallin
02-23-2024, 07:17 AM
What if I want to use the tools I have right now because I am finishing syrup right now and don't want to wait for a hydrometer to get delivered, like I said in my post?

If you want to finish "right now", then take your chances....if you want to finish it "right", go get a hydrometer. What's the hurry?

Andy VT
02-23-2024, 09:02 AM
I think a density measurement might theoretically work but you'd have to have really precise equipment that I suspect would cost more than a simple maple syrup hydrometer, and I feel it would take quite a bit of time to take a reading.
I may be missing it but I can't find anything in your posts about a hydrometer delivery pending.
Sap that has been boiled does have very good shelf life in the fridge, if you'd like to re-consider waiting for one to arrive, or a maple equipment dealer may have one in stock.
You might be able to borrow a hydrometer from a nearby producer or hobbiest, or bring a syrup sample to their sugarhouse for a test.
If you're averse to hydrometers for some reason many claim good luck with a refractometer.
But back to your original question, I suspect it's just that density on a scale is harder to do and more expensive than using the tried and true and cheap hydrometer.
Good luck!

DRoseum
02-23-2024, 11:44 AM
Volume changes with temperature. You would need to compensate for that as well as other considerations pointed out by others.

The advice here is solid, and i agree with suggestions to order a hydrometer or refractometer.

Andy VT
02-23-2024, 12:47 PM
I should mention that there is a cohort who resists instruments (other than thermometer) and goes by the "sheeting" or "apron" method (observing how the syrup drips off a metal spoon or spatula), and swears by it. I found it a little variable but with practice probably could get better at it but I've personally settled on using a hydrometer.
The sheeting/aproning method is best passed on from generation to generation in a mentor/apprentice model but there are youtube videos on it as well and you could experiment with it.
Andy

Maple dabbler
02-24-2024, 12:34 AM
If you want to finish "right now", then take your chances....if you want to finish it "right", go get a hydrometer. What's the hurry?

No hurry, I just like to break the rules and do little science experiments like this for fun.

220 maple
02-24-2024, 01:00 AM
Hey something to think about! Maple syrup is 7.1 degrees above the boiling point of water which changes every day! Yes I said it water has a different boiling point due to barometric pressure,
So when you’re doing your playing around, don’t forget the boiling point of water!
Mark220maple

buckeye gold
02-24-2024, 06:57 AM
The OP asked why more people don't use a common scale to determine syrup density. To me the answer is very simple and the K.I.S.S. approach applies. Density changes very rapidly when syrup is in it's final stages of finishing. A syrup hydrometer can be kept at hand and it takes you about 15 seconds ( i'm guessing ) to fill a cup and slip in a hydrometer, then you can repeat it immediately and it is 100% accurate all the time ( assuming your hydrometer is calibrated). When your running an evaporator, finishing and filtering all at the same time you don't want to mess with weighing checking barometer and calculating a density or even refer to charts. Look at a hydrometer and move on in the process. It's fine to play around in a kitchen, but in the sugar shack it's simple fast and accurate you want.

Andy VT
02-24-2024, 07:34 AM
No hurry, I just like to break the rules and do little science experiments like this for fun.

I can relate to the curiosity.
Looks like you're blazing your own trail on this one.
I'd say the first step would be to take some finished syrup or even some of your almost finished syrup, and compare the weight on your kitchen scale with some sap that you stopped boiling at, say, 216 or so. You'd have to measure the volume very exactly. And see if your scale can tell the difference.

buckeye gold
02-24-2024, 09:23 AM
A kitchen scale has a wide range of accuracy and acceptable levels of error. Your standard deviations will be wide as nothing is stable at that point. No matter what you do with a rudimentary piece of equipment you will not be able to establish a consistent level of accuracy. A hydrometer is a professional level piece of equipment manufactured with controls to insure a consistent level of accuracy. Have fun playing.

Swingpure
02-24-2024, 12:55 PM
I am always a little off traditional practices, but I make what I think is great syrup. Use the sap tap app for determining the temperature to make syrup at your location and for the barometric pressure that day. Both your location and the daily barometric pressure will change the boiling point of water or syrup. I always add about 2° to what the sap tap app says to that make 66.9% Brix syrup. I do not rely on that to finish my syrup, but it gets me close. I use an inexpensive refractometer you can get from Amazon to verify the Brix.

At times I can see from the appearance of the bubbles in the sap/syrup that it is getting close and you also do the drip test.

Without a doubt the hydrometer is the sanctioned method for testing Brix, but I have neighbour’s around me, who have been making syrup for generations who have never touched a hydrometer. The syrup is just for their family use and they make great tasting syrup.

I make great tasting syrup.

Once last comment, real syrup is thinner than many store bought syrups, so what you might think as thin, maybe just right.

buckeye gold
02-24-2024, 04:03 PM
Good point swingpure, we're making syrup not molasses or commercial pancake toppings. That may well be were the difference in expectations are.

ebliese
02-25-2024, 06:59 AM
But if your "syrup" is too thin, then it's Maple Light! Same great taste, less calories! :lol:

We had this instance our very first year-the first ever batch of "syrup" was too thin and not actually syrup. We ordered a digital thermometer and would finish to 7* above the boiling point of water for. We would check the boiling point every day we bottled. Now we use a hydrometer and a Murphy Cup.

Maple dabbler
02-26-2024, 02:16 PM
Hey something to think about! Maple syrup is 7.1 degrees above the boiling point of water which changes every day! Yes I said it water has a different boiling point due to barometric pressure,
So when you’re doing your playing around, don’t forget the boiling point of water!
Mark220maple

Good point. I looked up my local elevation (87 meters) and calculated the boiling point depression at about 0.5 degrees F less than at sea level. From what I can tell, local variation based on weather is even less significant than my very low elevation above sea level.

Maple dabbler
02-26-2024, 02:20 PM
I can relate to the curiosity.
Looks like you're blazing your own trail on this one.
I'd say the first step would be to take some finished syrup or even some of your almost finished syrup, and compare the weight on your kitchen scale with some sap that you stopped boiling at, say, 216 or so. You'd have to measure the volume very exactly. And see if your scale can tell the difference.

I know kitchen scales can be inaccurate, but you can calibrate the error by measuring a known weight close to what you are trying to measure. Water at a specific volume is a good thing to use to calibrate.

Having now tried my little experiment, I can say I won't be doing this again. The problem is you need a lot of syrup to get an accurate reading, and that just makes a big mess. The other problem is it's much harder to get an accurate volume reading than an accurate weight reading a wide mouth measuring cup just isnt accurate enough. Maybe if I had a large 1L graduated cylinder it would make sense, but that's another big mess to worry about.

In the end, I settled on temperature readings and I'll tweak my technique based on how the syrup feels after it cools.

berkshires
02-26-2024, 03:14 PM
Good point. I looked up my local elevation (87 meters) and calculated the boiling point depression at about 0.5 degrees F less than at sea level. From what I can tell, local variation based on weather is even less significant than my very low elevation above sea level.

Now you're just being silly. I looked up the variation in pressure over the last month for my area. It varied from 29.6 to 30.6. This would result in a difference in boiling point of over 1.6 degrees F from one extreme to the other.

Cheers,

GO

berkshires
02-26-2024, 04:03 PM
In the end, I settled on temperature readings and I'll tweak my technique based on how the syrup feels after it cools.

See my post above ^^^. This is enough to be off by several percent sugar concentration in your finished "syrup". If it's just for your use, okay, do what you will. But you might not be happy with the results.

GO