Figuring GPT numbers

[blissville maples]

So I've long wondered how others are coming up with their average sugar content to formulate their gallons of syrup per tap figures. I usually use 60 gallons of sap per gallon of syrup as I feel half my sap is 1.7-1.9 and half 1-1.2. I don't usually go lower than 1% occasionally.9. and I rarely ever see anything higher than 2.2. I keep records of sap gallons during transfers and every week or so jot down the corresponding sugar content... curious if other use similar methods. Hard to generalize this sort of thing across the board with all the variables and differences.

[DrTimPerkins]

There are many ways to do it...the most appropriate way depends upon what information is important to you. The simplest method, which most people do is to measure occasionally and guess at the average. Others measure more frequently and do a simple average. Another approach is to use the volume and sugar content to calculate the amount of syrup you'd make from a collection period. Likely the most appropriate way to get an idea of average sugar content over an entire season is to do a volume-weighted average (I won't bother explaining the math unless someone really wants it). This incorporates both how much you get during a period and the sugar content. That comes closest to what you'll end up with in terms of syrup.

[RC Maple]

I keep a record daily of how much sap I gather and the sugar content according to my sap hydrometer. At the end of the season I know how much syrup I actually made and I figure the average sugar content for the season based on that.

[ennismaple]

Up until now all our sap came into the sugar camp in a tank behind the tractor so we had a pretty good estimate (± 25 gallons per load) of how much came in and knowing how much you made (minus what's sitting in the pans) you get a reasonable estimate of sugar content. I also tend to check sugar content in the raw sap tank every day before I fire up the RO so I know how hard I need to push it. If I've got poor sugar I dial the concentrate down, great sugar I can dial it back a bit - found out the hard way last year I can't filter syrup fast enough when I'm making 20 Brix concentrate!

This year we're pumping 3000+ taps 4000 feet back to the sugar camp so we won't have an exact volume of sap coming in unless we install a water meter.

For us, an average year is 2.1 Brix back-calculated from total syrup made and sap delivered to the camp. A very good day we can be at 3 Brix, a poor day at the end of the season is closer to 1.5 Brix.

[GeneralStark]

To keep track of sap quantities I use a water meter on the pump out line of my electric releaser at the sugarhouse. Currently all my sap comes through that releaser. While not 100% accurate, this provides a good enough for me sense of how much sap I'm collecting. I use a hydrometer to test sugar content in my bulk tank.

I also use the MES app on my phone to get a good sense of how much syrup I should be making from the sap I've collected before each boil.

To calculate my seasonal production of syrup, I divide the number of gallons of syrup by the number of taps I have. The amount of syrup is determined by how many 15 gal. or 5 gal. barrels I have filled. This is not 100% accurate however as my 5 gal barrels hold more than 5 gal. when completely filled, but it's a good conservative estimate IMO.

Something to consider when doing your calculations, regardless of your preferred method, is the brix of the syrup you are producing. I like to have my syrup at 67 brix at the least. Also if you're trying to determine amount of syrup from sap and sugar content measurements, it's important to consider the potential issues with the Jones Rule of 86 it that's what you're using. Here's a good explanation of what I'm referring to:

https://mapleresearch.org/pub/m1013jonesruleof86/

[johnallin]

I'm sure I'm missing something, but wouldn't Gallons per Tap be: Gallons made / number of Taps?

[maple flats]

That's how I figure mine. The last 2 seasons I was down to 400 taps. I just take my total syrup produced and divide it by 400. I may grow back to a little larger in the future, but only at the sugarhouse, If I can't pull the sap to the sugarhouse I won't tap those trees, I'm done hauling loads of sap.

[minehart gap]

I'm sure I'm missing something, but wouldn't Gallons per Tap be: Gallons made / number of Taps?

I was thinking the same thing.
And sap per tap is total sap brought in/total syrup produced.

[blissville maples]

I guess my situation is quite different than most as I'm pulling sap from 6 different tanks and the makeup of trees varies. I have one Sugarbush that has alot of smaller trees with alot of reds in the mix, versus another with all sugar maple most over 20". The sugar contents vary alot between these 2, one sees 2.5 never less than 1.5 whereas the other rarely sees 2.0 and very often goes down to 1.0-1.25.

As I've said it's easy for me to jot down sap totals as I haul and I like disecting the numbers when time permits. I see very very different totals. One bush I calculate at .57 gallon syrup per tap and on the other end another is .38-.4.

I guess another thing to ponder is we try to keep losses to a minimum but there are some; filter press loss, membrane loss, and boiling to a denser brix.

I guess let me re phrase the question. On average through the season, if able to calculate based on sugar content measured, how much sap do most feel it's taking to produce a gallon of syrup?

[blissville maples]

Up until now all our sap came into the sugar camp in a tank behind the tractor so we had a pretty good estimate (± 25 gallons per load) of how much came in and knowing how much you made (minus what's sitting in the pans) you get a reasonable estimate of sugar content. I also tend to check sugar content in the raw sap tank every day before I fire up the RO so I know how hard I need to push it. If I've got poor sugar I dial the concentrate down, great sugar I can dial it back a bit - found out the hard way last year I can't filter syrup fast enough when I'm making 20 Brix concentrate!

This year we're pumping 3000+ taps 4000 feet back to the sugar camp so we won't have an exact volume of sap coming in unless we install a water meter.

For us, an average year is 2.1 Brix back-calculated from total syrup made and sap delivered to the camp. A very good day we can be at 3 Brix, a poor day at the end of the season is closer to 1.5 Brix.

And that 3 brix is on vaccumi I'm assuming? It seems the further north you go the higher sugar content, do others see this also? That's impressive, if I see 1.8-2 I'm happy!! Are these trees larger than average, have great crowns? I suppose juat food genetics is possible. Its hard for me to understand and will likely never know what contribute to these high sugar levels.

[Clinkis]

And that 3 brix is on vaccumi I'm assuming? It seems the further north you go the higher sugar content, do others see this also? That's impressive, if I see 1.8-2 I'm happy!! Are these trees larger than average, have great crowns? I suppose juat food genetics is possible. Its hard for me to understand and will likely never know what contribute to these high sugar levels.

I’m not too far from Ennismaple and my sugar content is similar and I think its fairly average for our part of the continent. Not sure if it’s climate or genetics? I almost never drop below 2 and not uncommon to be over 3. I’m all on vacuum as well and have mainly sugars with a few reds. And a mixture of small and large crowned trees. When I hear people talking about sugar content near one I cringe at the thought!

[DrTimPerkins]

On average through the season, if able to calculate based on sugar content measured, how much sap do most feel it's taking to produce a gallon of syrup?

You should do it for each run and keep a running total (we do this quite a lot).

Take your average sugar content for a run and calculate the number of gallons required to make a gallon of syrup. Use the modified Jones Rule of 86 for this.
https://mapleresearch.org/pub/m1013jonesruleof86/

Then divide the total number of gallons of sap in that same run by the value calculated above. That should tell you (ballpark) how many gallons of syrup you will make from that run.

Of course that misses any losses you mention, but you should try to minimize those as much as possible, however there is always at least a 0.5-1% "shrinkage" for each run.

[blissville maples]

You should do it for each run and keep a running total (we do this quite a lot).

Take your average sugar content for a run and calculate the number of gallons required to make a gallon of syrup. Use the modified Jones Rule of 86 for this.
https://mapleresearch.org/pub/m1013jonesruleof86/

Then divide the total number of gallons of sap in that same run by the value calculated above. That should tell you (ballpark) how many gallons of syrup you will make from that run.

Of course that misses any losses you mention, but you should try to minimize those as much as possible, however there is always at least a 0.5-1% "shrinkage" for each run.

"Shrinkage for each run" haha that's good. And true, I've heard others say also, you put so many gallons thru the rig at so and so percent and never end up with what you thought you would!!

I remember when I first started making syrup 10-12 years ago in my woodshed, I actually swore for a day that some sugar was evaporating!! The mind is always willing to toss in a few curve balls!

[blissville maples]

I’m not too far from Ennismaple and my sugar content is similar and I think its fairly average for our part of the continent. Not sure if it’s climate or genetics? I almost never drop below 2 and not uncommon to be over 3. I’m all on vacuum as well and have mainly sugars with a few reds. And a mixture of small and large crowned trees. When I hear people talking about sugar content near one I cringe at the thought!

You guys don't know how lucky you are and I mean that! Wow makes me want to pack up and head north. So last year was horrible down here and I mean bad. Guys right out of the gate started at 1.5 and within a week dropped to 1. By third week of March I was hearing of some at 3/4%

Last year I saw one run of 1.9 , just days later it was down to 1.5 and this was on my better bush. The sugar just wasn't able to hold out. We had a 2-3 day freeze and it bumped up 2/10 for a couple days lol....woo hoo.

But no that's impressive for the sugar to be holding like that. I guess some are coming in at 40/1 after all

[minehart gap]

I need to figure out how to get my "shrinkage" down to 0.5 - 1%.
I'm pretty sure that a lot more of my hard work goes down the drain from washing the drawoff pot every boil and the filter press hoses (I rinse the press with sap but loose syrup when changing hoses around) and the bottler, ect... than 0.5 - 1%.

[ennismaple]

And that 3 brix is on vaccumi I'm assuming? It seems the further north you go the higher sugar content, do others see this also? That's impressive, if I see 1.8-2 I'm happy!! Are these trees larger than average, have great crowns? I suppose juat food genetics is possible. Its hard for me to understand and will likely never know what contribute to these high sugar levels. Yes that's on vacuum. We generally get a few runs per season that are at or above 3%. We seldom drop below 2%. The older section of our woods is mostly a mono-culture of sugars in a woodlot with a lot of very old trees. Our "New Bush" is mostly 16"-18" trees and has only been tapped for a decade. Our winters can be harsh and long - we've been frozen solid since the start of the year. During the season we'll get several week long freeze-ups, which helps the sugar content.

[DrTimPerkins]

SSC tends to start a tad low, then spike up early in the season, then trend downward for the remaining season, with small, fleeting upticks after freezes. SSC tended to be higher than average in Underhill, Vermont (and surrounding areas) in 2019 and lower than normal in 2020. We had an article about it in the Nov 2020 Maple News. The primary figure from that article is below.

21963

[Amber Gold]

Here, all sap gets trucked to the sugarhouse and run through a meter with a sap sample taken. I keep a spreadsheet going with a running total for the season. At the end of the season, I divide the syrup produced by number of taps. Most seasons, I'm 55-60:1 for the season.

Also, based on my spreadsheet, the math never works out...syrup just disappears.