Frozen sap % question

[Trapper2]

We are going to have great conditions the next 3 days, 40s during the day and 20s at night. But 2 solid days of freezing temperatures after that.
I assume my buckets will be partially froze when I get to them on Friday morning again. My question is, if my sugar content in a full melted bucket is 2%, but I remove the ice from another bucket on the same tree that is 50% frozen and only test what is liquid, what do you think the sugar content will be in that bucket. I will test and post results next week.. Your opinions and guess's please.
15770
Thanks,Trapper

[5 Oaks]

I bought a refractometer just for this once. I had ice in my buckets. I don't remember exact numbers but I know from then on any ice in the bucket was throw on the ground.

[Cedar Eater]

Almost double. Very little sugar stays in the ice, but there is some. I'll guess 3.6.

[maplefarmer]

I did this in the past, it will raise sugar content, my guess is 4%

[Trapper2]

You guys are getting me excited with talk of 3.5 +.
Instead of making a bigger evaporator maybe I should be thinking about a walk in freezer.

[mol1jb]

I have 2 chest freezers I use with 9 5gal buckets total. Makes for a much faster boil the next morning.

[Cedar Eater]

Concentrating by freezing is more expensive than concentrating by boiling, but it will cut down on the evap time.

[Clinkis]

Concentrating by freezing is more expensive than concentrating by boiling, but it will cut down on the evap time.

How do you figure? Freezing requires almost zero labour and electricity cost would be very minimal? Regardless of the fuel source for boiling I would think it would cost more then the small cost of electricity.

[c0ps]

We are going to have great conditions the next 3 days, 40s during the day and 20s at night. But 2 solid days of freezing temperatures after that.
I assume my buckets will be partially froze when I get to them on Friday morning again. My question is, if my sugar content in a full melted bucket is 2%, but I remove the ice from another bucket on the same tree that is 50% frozen and only test what is liquid, what do you think the sugar content will be in that bucket. I will test and post results next week.. Your opinions and guess's please.
15770
Thanks,Trapper
From my own testing. I say 4 percent

[Tapline]

I just pulled all the ice out of my buckets this morning and checked the sugar percent of the unfrozen when I got back the the shack. Out of one woods the sap was 6 percent and the other wood the sap was 4 percent.

Sent from my SM-S120VL using Tapatalk

[Eds Constructors]

I would have to agree that freezing is more efficient than boiling for sure, as well as taking from sugars only when possible is best, In my own experience taking from reds and sugars, sugar content is diluted and overall flavor weaker. In my opinion only! No facts to back it up other than my own. I've tapped 12 sugars this year and received about 100 gal of sap with about 1.5 gal so far with 45 to boil yet I'm feeling good with some extra sweet stuff! Lots of luck to you all! And I throw out all my ice, sometimes it can decrease boil times by as much as half!

[Cedar Eater]

How do you figure? Freezing requires almost zero labour and electricity cost would be very minimal? Regardless of the fuel source for boiling I would think it would cost more then the small cost of electricity.

Electrical cost won't be very minimal. It just won't be easy to separate it from your normal winter electrical bill. ROs are a more efficient way of concentrating the sugar. For those who boil with wood fire, the wood is usually almost free and the labor is all just part of the process. So it is wood firing that is minimal.

[acafro]

I've done this experiment a few times last season, I've melted down the ice and had sugar content as high as .75%, usually in the area of .5%. IMO that's a loss if I pitch it. But I was also hurting for sap last season.

Sent from my SM-G935V using Tapatalk

[Clinkis]

Electrical cost won't be very minimal. It just won't be easy to separate it from your normal winter electrical bill. ROs are a more efficient way of concentrating the sugar. For those who boil with wood fire, the wood is usually almost free and the labor is all just part of the process. So it is wood firing that is minimal.

The average large chest feezer uses $10/month of electricity. That's minimal in my books. And yes I agree that an RO is a much more effecicient way to concentrate sap but, as that is not an option to many producers, partially feezing and removing the ice gives small producers another option to reduce their boiling time.

http://homeguides.sfgate.com/much-run-freezer-per-month-67647.html

[Cedar Eater]

The average large chest feezer uses $10/month of electricity. That's minimal in my books. And yes I agree that an RO is a much more effecicient way to concentrate sap but, as that is not an option to many producers, partially feezing and removing the ice gives small producers another option to reduce their boiling time.

http://homeguides.sfgate.com/much-run-freezer-per-month-67647.html

If you keep cycling new warm (above freezing) stuff into a freezer and half-frozen stuff out, the freezer compressor will run much more often than average. Think more like your A/C cost in the Summer. There will be a slight offset because the heat pumped out of the freezer and released into your house will decrease your home heating costs, but then you will also be opening the door to bring the sap in and out more often so that will offset that offset. If freezing was cheaper than boiling for concentrating the sugar, a lot more of it would be occurring in the industry. When Mother Nature does the freezing for you and you toss the ice out of the buckets, the .5% loss of sugar with the ice makes sense. When you pay to do the freezing it really just becomes more a matter of convenience. That's totally acceptable because your convenience is worth something, but the economics just isn't there.

[Clinkis]

I will respectfully disagree with you. As most people are already running a freezer anyways the increased cost would probably be less then $10. Even if it was double someone like myself who boils with propane would not be long recouping the $20. Im not advocating that this is the best way to concentrate. Like I said, it's an option for some people who would like to save some boiling time and relatively economical one.

[saphound]

What do you do when your 3/4 full buckets are frozen solid...and I mean solid. Now all the sugar is locked up in ice. I don't see how I can discard any of it now as it melts. :confused:

[Trapper2]

I did a test this weekend on my original posting. The buckets were 3/4 frozen. First I checked the concentrate, that came in at 5.5%. Then I melted the ice in a bucket on my preheat vat. That checked in at .9%. So like 5 Oaks said, if you have plenty of sap, throw the ice away.1588815889

[wmick]

Don't want to take sides, but it is an interesting discussion... and a bit of math we can look at.

It takes approx 4200 Joules of energy to change a Liter of water by one degree Celsius. (please forgive my "Canadian" :D)

So, if we assume a room temp starting point (20 degrees C) it will take 84 Kilo-joules of energy to bring a Liter of Water from room temp to freezing point. .... and then another 333 KJ to crystallize it.. So a total of 417 KJ..

To bring it from 20 to 100 (boiling point), it will take 336 KJ of energy... And then here is the Kicker - It takes an additional 2261 Kilo-joules to turn a Liter of 100 degree water into vapor.

So--- without taking Losses, efficiency or Energy Cost into account, We are looking at 2600 to 417 (boiling vs freezing)..

No equipment efficiency or coefficients have been taken into account here, but I expect, based on the math, that in comparing a propane propane burner to freezer... the freezer would win, hands down... Now the only setback will be throughput. You are likely not going to be able to find a deep-freezer that separate 10 or 15 gallons of water per hour... (like many small evaporators can)

[Trapper2]

In Wisconsin you can use Mother Nature as she always freezes my sap the day before I can empty buckets Ha Ha

[hansel]

What do you do when your 3/4 full buckets are frozen solid...and I mean solid. Now all the sugar is locked up in ice. I don't see how I can discard any of it now as it melts. :confused:
The sugar will be the first to melt. The first third of melting is definitely keep. Separate that out then check until the melted sap is too low of a percentage for you to bother with.

[Michael Greer]

My buckets are frozen solid today, so if I throw out the ice, the sugar content will be ZERO. Freezing the buckets under just the right conditions will indeed leave you with a higher sugar content, but it's seldom exactly the right condition.
As to freezing sap in the chest freezer....heating and cooling are the largest uses of energy in the house. Those freezers are costing you plenty...most of your electric bill I'm guessing. The cold sky of a winter's night is free.

[Cedar Eater]

So--- without taking Losses, efficiency or Energy Cost into account, We are looking at 2600 to 417 (boiling vs freezing)..

No equipment efficiency or coefficients have been taken into account here, but I expect, based on the math, that in comparing a propane propane burner to freezer... the freezer would win, hands down...

But the issue here is cost (expense), not energy efficiency. The comment that some are taking exception to is that freezing is an expensive way to concentrate the sugar. You being Canadian, you probably pay much more for electrical power than we pay here in the US. At least that's my understanding based on hearing from other Canadians when discussing electric evaporators. If we compare only electrical methods and take only concentrating into account, ROs win over freezers or boilers, but then we go into the other aspects of concentrating sugar. Without the sterilizing effect of boiling, concentrated sap will spoil more quickly and it will never caramelize into syrup.

So boiling has to happen eventually. But until it does, energy cost and, as you say "throughput", along with less concrete issues like the cost of sap storage and whether the labor of boiling is work or recreation are the factors of "expense", not energy efficiency. In other words, leaving reverse osmosis out of the picture, using heat pumping to do what you could do with evaporation is only cost effective when you impute the costs of your labor high enough and the cost of cold sap storage low enough.

Which brings us back to convenience. Is it more inconvenient (expensive in all senses) to boil with "free" wood, propane, natgas, or electricity, or is it more inconvenient to manage the storage, freezing, and concentrating of sap by pumping the heat out of it? My freezers are full of mostly venison in the Winter and Spring, so I would have to buy another freezer which will sit idle and take up space until the next sap season. That would be far more inconvenient than evaporation, especially considering how minimal evaporation labor is with electric evaporators. If someone else fills their freezers late in the year and has plenty of capacity during sap season, there are still the issues of ice management and duty cycling of their freezers (shortening their lifespan) to add into expense.

[Clinkis]

You seem to be missing the point that I've been trying to make. No one is suggesting that producers should throw away their RO's and evaporators, start buying chest freezers and trying to make finished syrup in them. I'm just saying that a small producer who wants to save some boiling time could use this as an inexpensive option. Obviously it's not practical on a large scale.

I'm pretty much out of venison now so I have lots of room in mine but luckily I have an RO. Hopefully put a couple wild turkeys in it soon.

[Cedar Eater]

But the point is that it may not be as inexpensive as you think and it won't be for those who lack the freezer space and have different priorities. The extra that they spend on electricity might mean a commitment of extra time at their day job to pay for that juice or it might mean that something else in their budget has to give. The post you took exception to said only, "Concentrating by freezing is more expensive than concentrating by boiling, but it will cut down on the evap time." To which you asked me "How do you figure?" Obviously, I can't say for certain what would happen in your case, but I can tell you how to find out. Load your freezer with sap and monitor the power consumption for however long it takes to get the sap to the right level of frozen. Calculate the cost of that extra power. Add the time cost of doing it and then compare it to the cost of boiling ordinary sap, including the time cost of boiling. Then you'll know.

Good luck in your turkey hunting.

[Clinkis]

Perhaps it best we just agree to disagree on this. I'm pretty sure we can both come up with numbers and situations to support our arguements. I strongly believe that in some situations it would make sense and be cheaper and in other situations it wouldn't.

[saphound]

The sugar will be the first to melt. The first third of melting is definitely keep. Separate that out then check until the melted sap is too low of a percentage for you to bother with.

Interesting. Is that because the sugar was the last to freeze so it would be contained in the outer couple inches of ice, and so would be the first to melt? I didn't chuck any of the ice because we have no snow and I needed it in there to keep the sap cold. Collected today, all the ice had melted and all the combined sap tested at 1.9. Was going to boil today but it was wicked windy and I boil outside and have a hard time keeping a good boil in high wind. Now this weekend is going to be cold.. lows around 10F..highs around 30F. I think I'll chuck some ice this weekend and boil on Monday.

[helptheold]

The sugar will be the first to melt. The first third of melting is definitely keep. Separate that out then check until the melted sap is too low of a percentage for you to bother with.


Interesting. Is that because the sugar was the last to freeze so it would be contained in the outer couple inches of ice, and so would be the first to melt? I didn't chuck any of the ice because we have no snow and I needed it in there to keep the sap cold. Collected today, all the ice had melted and all the combined sap tested at 1.9. Was going to boil today but it was wicked windy and I boil outside and have a hard time keeping a good boil in high wind. Now this weekend is going to be cold.. lows around 10F..highs around 30F. I think I'll chuck some ice this weekend and boil on Monday.

Very interesting. I was thinking of doing the freezer method (just a few taps) and asked my husband what he thought as he is a chemist. He said that since the sugar freezes last, it will actually be in the middle of the bucket. So his advice was to chuck the stuff that's melted first & keep the center. But what you're saying is different from that so now I'm interested to see which is correct! Gonna get a refractometer next year & turn him loose on a few buckets for experimentation. If I'm lucky I'll get him interested enough so that he'll try to build a RO for me. Sometimes he misses the lab work.

[Cedar Eater]

Very interesting. I was thinking of doing the freezer method (just a few taps) and asked my husband what he thought as he is a chemist. He said that since the sugar freezes last, it will actually be in the middle of the bucket. So his advice was to chuck the stuff that's melted first & keep the center. But what you're saying is different from that so now I'm interested to see which is correct! Gonna get a refractometer next year & turn him loose on a few buckets for experimentation. If I'm lucky I'll get him interested enough so that he'll try to build a RO for me. Sometimes he misses the lab work.

I would think that since the sugar is heavier, the water ice would normally float above it until the very last and maybe the bottom would even be unfrozen syrup. But how would you ever control what melted first?

[berkshires]

But how would you ever control what melted first? Sugar water has a lower melting point than plain water. So the sugar water melts first.

Gabe

[Cedar Eater]

Sugar water has a lower melting point than plain water. So the sugar water melts first.

Gabe

But the whole frozen block isn't necessarily going to be heated evenly. Maybe the top will be warmed before the bottom or one side will be warmed before the other.

[saphound]

Hi helptheold..(love that username!), I actually think your husband may be right. From what I've observed, you get skim ice on the top first, but then the sides start freezing and squeezing unfrozen sap to the middle. If your running tubes to a bucket on the ground, like I do, the bottom is protected from the cold the most. If hanging buckets, not so. So that would suggest the sugar should be in the center of the ice, if frozen solid...not in the outer few inches. Now, I watched daily as the ice melted from the outsides, with the center melting last. And testing the sap as it melts has shown it to be high sugar first, then going down as it melts. So which the heck is it?! I think you need your chemist hubby to run some tests and explain it to us, lol. We'll be waiting. :)

[helptheold]

I would think that since the sugar is heavier, the water ice would normally float above it until the very last and maybe the bottom would even be unfrozen syrup. But how would you ever control what melted first?

That's a very good question, I've made some notes on what to have him test and will add that to the list of questions. Right now he's tired of me complaining about the season ending with our crazy weather.



Hi helptheold..(love that username!), I actually think your husband may be right. From what I've observed, you get skim ice on the top first, but then the sides start freezing and squeezing unfrozen sap to the middle. If your running tubes to a bucket on the ground, like I do, the bottom is protected from the cold the most. If hanging buckets, not so. So that would suggest the sugar should be in the center of the ice, if frozen solid...not in the outer few inches. Now, I watched daily as the ice melted from the outsides, with the center melting last. And testing the sap as it melts has shown it to be high sugar first, then going down as it melts. So which the heck is it?! I think you need your chemist hubby to run some tests and explain it to us, lol. We'll be waiting. :)

How very interesting, that really seems to contradict what he told me. I trust that he knows what he's talking about (PhD in organic chem & now works in pharmaceuticals) but there could be things different about sap then what he's used to. I will let everyone know what he figures out next year, I had thought I had some sap still in the freezer but I don't so we'll have to wait.

[saphound]

Well, after more thought, I have one hypothesis on how this could be. The high sugar sap gets trapped in the center because it freezes last. But because it thaws first, it would have to melt it's way down to the bottom of the bucket and then ooze up the sides..giving the illusion that the sides are melting first, but actually the higher sugar sap is finding it's way to the bottom and creating a pathway to ooze up around the sides of the ice. If that's not it I don't know how else it could happen. Sugar can't just migrate through solid ice. :confused:

[Eds Constructors]

Your husbands right! out of 4- 6 gal. buckets, I wound up boiling 13-14 gal of liquid and got 2 quarts and a 1/2 pint, quite satisfied with the results. Nature's RO, best thing going; (tip; check buckets before starting fire-lol)

[berkshires]

But the whole frozen block isn't necessarily going to be heated evenly. Maybe the top will be warmed before the bottom or one side will be warmed before the other.

Maybe if it's in direct sun. But the fact is that once you have meltwater in a bucket, the water is a **** good conductor of heat (which is why the solder on pans don't melt in the 1000 degree furnace that's the inside of an arch).

Also, if you lift out a half-melted block of ice, you'll see it's a little bit spongy. Basically as it melts, the sugar is melting out first, leaving ice crystals behind. Think about what happens when you throw salt down on ice. It melts out from the salt crystals first. Same thing is happening at the microscopic level.

GO

[helptheold]

Maybe if it's in direct sun. But the fact is that once you have meltwater in a bucket, the water is a **** good conductor of heat (which is why the solder on pans don't melt in the 1000 degree furnace that's the inside of an arch).

Also, if you lift out a half-melted block of ice, you'll see it's a little bit spongy. Basically as it melts, the sugar is melting out first, leaving ice crystals behind. Think about what happens when you throw salt down on ice. It melts out from the salt crystals first. Same thing is happening at the microscopic level.

GO

OK further discussions with the hubby yielded more information. If you let a bucket of sap freeze all the way solid, then when it starts to melt what berkshires said is correct. How it gets out he wasn't clear on (or I just didn't understand) but the sugar will be in the water that melts first. So if you've run out of road salt to use on your driveway you can use sugar but it will cost you more ;) He reminded me that the town we were living in a few years ago did that when we had a bad winter and they ran out of salt, they were using beet sugar.

However, if you don't let the bucket freeze all the way through then the ice on the sides/top will have a lower sugar content as the freezing process is pushing the sugar to the middle. That's why you can remove the ice from the sides and not really worry about it. It will have sugar in it but not as much.

Therefore both methods will work but hubby did note that letting a bucket freeze solid & then letting it melt is very inefficient. The better way is to leave it in the freezer (or outside) and scoop out ice on the sides/top every few hours if you do the freezing concentration method.

https://en.wikipedia.org/wiki/Fractional_freezing

[saphound]

Never knew you could melt ice with sugar. :-|

[helptheold]

Never knew you could melt ice with sugar. :-|

I'm sure it's special blend of sugar. When my husband tells me things there's often the assumption that I know more than I really do. He often forgets that I didn't get a PhD & I didn't gain his knowledge just by signing the marriage certificate ;) Kind of annoying as he dumbs things down for other people.

[berkshires]

I'm sure it's special blend of sugar.

Any sugar would do it. Works by the same action as salt, just not as effectively.

GO

[saphound]

I've got about 40 gallons of sap that's going on two weeks old now. It's either been frozen solid or had ice floating in it the whole time. It's still crystal clear with no odor or bad taste and I did remove some of the ice..maybe about a bucket full of ice from the 40 gallons. I tested it yesterday and it hasn't changed much from when it was collected. I think I read this once here long ago.. that the sugar will convert into starch or something after a time. Could that be why my sugar level didn't improve?

[mellondome]

Bacteria in the sap consume the sugar.

[Clinkis]

If sap is stored for prolonged periods of time the growth of micro organisms will consume sugar. If your sap has been kept cold then this shouldn't be an issue. That said, your sap will usually spoil before there is a significant drop in sugar. I had some sap last week that I stored a bit too long and was cloudy and on the verge of spoiling. The sugar content had dropped maybe a 1/10 of a percent. It made some really nice dark syrup.

[saphound]

Ahh, that was it. Thanks Mellondome and Clinkus. I'll try removing some more ice and see if I can get the sugar to improve.

[Daveg]

I had some sap in jugs on trees form a gradient with some 40-50% sugar in the top 1/2" of slush.

[Daveg]

Poor man's RO.

[saphound]

I've noticed that too, Dave...slushy ice on top as the sides turned to ice. But some have said sugar is heavier and sinks to the bottom so I wasn't sure what was what.

[Helicopter Seeds]

I don't have the refractometer so never tested the levels, but I did boil some ice in a small pan last year and got syrup, so I convinced myself to keep what I harvested. Weather improved today, was supposed to be a high 32F, but it hit 40F, so I expect some sap. Better yet, next few days look ideal, 20s at night, 40s days.

Since I am trying to conserve firewood, I am planning to separate my ice from sap in my two barrels, do the concentrate first and then see what it yields. Then If I run out of wood, I will have at least gotten the best of it.

[saphound]

Helicopter Seeds, If you have a pic of your brick arch, I'd love to see it. I saw your pics of the unmortared arch, is it like that?

[Helicopter Seeds]

Here are a couple: I got a grate designed for a barrel stove, set on bricks instead of legs because they were curved. CDL 18 x 48 divided pan. Last year I used five steam pans, I kept one as a preheater, also use as a filter rinse.1609216093

[saphound]

Nice, thanks. Where did you find steam table pans with handles like that? Don't recall seeing any like that when I was shopping around for them.

[Helicopter Seeds]

Nice, thanks. Where did you find steam table pans with handles like that? Don't recall seeing any like that when I was shopping around for them.
the handles are actually a snap into place separate item. I got them at chef's emporium in Orange. I think maybe an extra ten bucks each, but I use them for parties too.

[Run Forest Run!]

the handles are actually a snap into place separate item. I got them at chef's emporium in Orange. I think maybe an extra ten bucks each, but I use them for parties too.

I've searched everywhere for a link to those types of handles but can't find anything like that. Chef's Emporium link only has aprons etc. Any chance you have a link?

[Helicopter Seeds]

I bought them at the retail store in Orange CT, they don't have that much online compared to the store. I just looked too.
I would try the good old fashioned telephone. They are very helpful and I bet would be able to ship.
I cannot remember the brand either.

Well worth it. If I had not gotten the bigger pan, I would have gotten two more of those.

[hansel]

Should get a good run of sap the next 2 days, then let it freeze solid Wednesday night. Thaw and discard when it warms.

[Mark B]

Not to beat the horse any longer, but I actually found an online study of sugar content vs frozen volume. Basically the study said the 1st 1/3 of your ice has little to no sugar content. If your buckets are more then 1/3 frozen then allow to thaw till only 1/4 to 1/3 of the volume remains frozen (since the ice containing sugar content will thaw first). Discard the remaining ice as it will contain little sugar content.