Question about Hydrometers vs a Thermometer?

[chuckinduck]

So a friend and I have been trying our hands at syrup for the past couple of years. We both only use a candy thermometer, and have had good results, but I'm contemplating getting a hydrometer. My syrup always seems a little "thin", despite boiling to 219. My conversion ratios also seem off, for example. I made 7 pts out of 30 gallons of raw sap last weekend, and that was off Reds/Silvers, which aren't considered to be the preferred maple from all I've read. So I guess my question is, if syrup becomes syrup at 217-219, why is a Hydrometer so much better for testing? Seems like syrup would be syrup, and thus the proper density at 217-219, so as long as I can get it to the specific temp, I should have the right density, and thus no need for a Hydrometer. Please help clear up the confusion, as I must be missing something. What I'm really looking for is a good reason to buy a hydrometer, in hopes I'll get a higher quality/thicker syrup. Thanks Guys.

[PerryW]

thermomters must be corrected for atmospheric pressure and do not have the resolution to accurately determine syrup density. You can get close by checking the boiling point of water and adding 7 degrees (f) but not accurate enough for commercial use.

A hydrometer directly measures density, and iis much more accurate.

[RileySugarbush]

A hydrometer would really help you out. The problem with using boiling point is that it can change, even during a single day, based on atmospheric pressure. You can compensate some by checking what the boiling point of water is just as you are finishing and adding 7°F.

A hydrometer is not sensitive to atmospheric pressure so that works a bit better. it will have two red lines on it. The cold test line is where it should float when your syrup is at 60°F, and on mine is marked at 67 Brix. The upper red line is where it should float when hot (211°F and 59 Brix on mine). Even though you draw off at a higher temp then that, the sample quickly cools a little in the hydrometer cup and this 211 is approximately the temp you are likely to be measuring at.

If you really want to get it spot on, then the best thing to do is to me sure the actual temperature in the sample and look up the correct reading for that temp. That is what we do in our water jacket bottler. Draw off a little thick, filter into the bottler and bring up to 190°F, and test/adjust with distilled water to correct density for that temperature. We also have a refractometer that is quicker to measure density. Both methods agree.

A hydrometer is reasonably inexpensive and a good thing to have. But if you just want thicker syrup, try the boiling water temp check and maybe take it just bit over 7° above that. If you start getting sugar crystals, you went a little too far.


( looks like Perry thinks and types faster than me!)

[sapbrush]

Hi i use only a thermometer, ive done this long enough that i can see when it becomes syrup, as the old timers say when it starts sticking to the back of a spoon your done, and i have checked it with a hydrometer and it is syrup so i guess forget all the new gadgets and just have fun, isint that what its all about anyways

[chuckinduck]

Thanks for the help guys. It clears it up. My concern is by relying just on the thermometer, I might be getting it close, but not close enough, and by going a degree over, I may then be adding sugar sand to my finished process.

[chuckinduck]

Thanks guys, that does clear it up. I've always just went to 219 w/out a check of what water boils at on any given day, but I do like the idea of the hydrometer for a more accurate reading. I'm just cautious of getting it to close for fear of adding sugar sand and making it a mess. I guess I'll get more proficient over time.

[gbwez]

I have a digital candy thermometer that over reads by 3 or 4 degrees... i.e. it says 219 when the actual temp is 215 or 216

[happy thoughts]

Yeah, I think you're sap/syrup ratio may be telling you something. Could be, probably isn't. That said, I also just use a thermometer and have for these first 6 years of home sugaring. For the small quantities I make, under 4 gal/year, a hydrometer is kind of a luxury and I can be pretty clumsy. It's on the wish list but maybe when I start making lots more syrup.....

I think it can be done with a thermometer only, especially after a few years experience. Syrup making is basically candy making and people make candy all the time just going by the looks and behavior of a sugar solution. Like sapbrush says, you'll get a feel for it. But that said, there are a couple of things you need to consider when using a thermometer.

First don't assume the boiling point of water is going to be 212F at your house at any given hour. Your scale may be off and barometric pressure will greatly affect boiling point. For instance, yesterday when I made syrup the calculated boiling point of water was just a hair under 213F at my house.

Always test your thermometer first in boiling water. By adding 7+ degrees to syrup, that will give you a rough idea when to start being careful. Since few thermometers read fractions of degrees, I just add 8. You don't want to add just 7 because more than a 7 degree difference is needed for syrup, so round up one.

The type of thermometer you use is also going to make a difference. I personally prefer digital ones because they're easier for me to read and more responsive to temp changes. And some like mine have a temp alarm which is a nice feature.

With a digital thermometer one thing you'll notice is the way a temp fluctuates. That made me realize that not all of the syrup in a pan is of the same temp. There are hotter currents. When I look for a finished temp I want to see that in a fairly repeated state. Not a momentary flash then down again. IOW, when I feel the entire pot of syrup is at the right temp, not just a small passing current.

When sap approaches syrup it takes on some subtle changes for me and the top begins to take on a certain sheen. Some people look for sheeting- when hot syrup poured from a spoon forms a sheet instead of individual drops. I look for syrup that starts to coat a spoon. I would rather deal with over dense syrup that may eventually form rock crystals which happened once in one small batch I made, than under dense syrup that may spoil in storage.

Now back to your original question! All of the above are good reasons why a hydrometer works better. You look at a line once and not only are you done you can be pretty sure of it. But a thermometer can be made to work also:)

A boiling point calculator is here:

http://www.csgnetwork.com/prescorh2oboilcalc.html

If you don't have a barometer, take the pressure reading for your area from a weather site of your choice like accuweather.com etc.

[happy thoughts]

Thanks for the help guys. It clears it up. My concern is by relying just on the thermometer, I might be getting it close, but not close enough, and by going a degree over, I may then be adding sugar sand to my finished process.

I think you're under a misconception here. Sugar sand will form during boiling. You can't avoid getting to those temps WHEN FINISHING. As soon as it's syrup, you filter. it is after filtering that you want to avoid bringing the syrup above 200F or more sand will form. This is what I think you're thinking of.

Some people don't bottle immediately after filtering so sometimes the syrup must be reheated before packing. Syrup only needs to be around 185F for a good seal and to help sterilize the bottle so that's the reheat temp many people shoot for.

[chuckinduck]

I think you're under a misconception here. Sugar sand will form during boiling. You can't avoid getting to those temps WHEN FINISHING. As soon as it's syrup, you filter. it is after filtering that you want to avoid bringing the syrup above 200F or more sand will form. This is what I think you're thinking of.

Some people don't bottle immediately after filtering so sometimes the syrup must be reheated before packing. Syrup only needs to be around 185F for a good seal and to help sterilize the bottle so that's the reheat temp many people shoot for.
Right, the sand forms after you've reached syrup and start to "burn" the syrup/sugar, not the "near syrup", correct? My fear was getting it too hot, that I would cause more sand to form, not so much when I got to the point of re-heating. Once I've reached syrup, do you filter immediately (219), back into the pot, and then let it cool, until 185-190? Or re-heat and then put it in the jugs?

[happy thoughts]

Right, the sand forms after you've reached syrup and start to "burn" the syrup/sugar, not the "near syrup", correct? My fear was getting it too hot, that I would cause more sand to form, not so much when I got to the point of re-heating. Once I've reached syrup, do you filter immediately (219), back into the pot, and then let it cool, until 185-190? Or re-heat and then put it in the jugs?

Someone else will have to answer your filter question. I don't filter, I let the sand settle out in glass jars kept in the fridge. Then I very carefully pour off the clear stuff and reheat to about 185-190F. The syrup I bottled yesterday is beautiful. Totally clear and not a trace of sand in the jar bottoms even after about 24 hours.

Can you tell I'm not really much into gadgets lol :) I'm really too small a producer to make most worth it to me. I'm more of a make it do or do without person at this stage. But ask me next week now that I have a simple steam pan arch and am eying up more trees to tap :lol:

[PerryW]

Right, the sand forms after you've reached syrup and start to "burn" the syrup/sugar, not the "near syrup", correct? My fear was getting it too hot, that I would cause more sand to form, not so much when I got to the point of re-heating. Once I've reached syrup, do you filter immediately (219), back into the pot, and then let it cool, until 185-190? Or re-heat and then put it in the jugs?

I would say, no and yes. Sugar Sand starts forming way before you reach syrup. You even get a type of sugar sand deposit in your back pans.

But I agree, the RATE OF SUGAR SAND FORMATION goes up the higher the density. If you go above syrup a couple points, the deposits are worse, and burnt spots can even appear near the drawoff.

[wnybassman]

For nearly ten years I thought I was making syrup, then I bought a hydrometer and realized I wasn't.

[chuckinduck]

thanks for everyones help. Ordered a hydrometer yesterday from a local michigan company.......should be here tomorrow, just in time for this weekend. Hopefully I will be making "syrup" this weekend, and test what I have now, to see if its syrup, or just a heavy sugar water. :)