Sap Volume not adding up to Syrup volume

[SenecalsSugarHouse]

So today as we fired up the evaporator for maybe the last time I started figuring out how close we were to actually making what our sap said we should. All together for the season we have had 7280 gallons of sap with an average sugar conent of 1.97%. So for the sake of being conservitive I figured 45 gallons to 1 gallon. That came up to 161 gallons. If I went to 1.5% sap it was 145 gallons, we only made 100! Any ideas on what we are missing. Some of the syrup may be a little heavy but with no finishing pan it is what it is. Could that be the answer or is it something else? Thanks for any ideas,
Dave

[allgreenmaple]

So today as we fired up the evaporator for maybe the last time I started figuring out how close we were to actually making what our sap said we should. All together for the season we have had 7280 gallons of sap with an average sugar conent of 1.97%. So for the sake of being conservitive I figured 45 gallons to 1 gallon. That came up to 161 gallons. If I went to 1.5% sap it was 145 gallons, we only made 100! Any ideas on what we are missing. Some of the syrup may be a little heavy but with no finishing pan it is what it is. Could that be the answer or is it something else? Thanks for any ideas,
Dave Try another syrup hydrometer to verify.

[DrTimPerkins]

Several possibilities:

1. Sap hydrometer is off (reading too high)
2. Syrup hydrometer or measurement technique is off (reading too low...are you sure it was dry before putting it in the syrup....and was the syrup temperature corrected for).
3. Sap and/or syrup volume measurements are off (too high -- tanks,especially Poly-tanks are notoriously bad for volume measurements).
4. Calculation error (although your math seems correct).
5. Some combination of the above.

[KenWP]

Are you boiling right away or waiting a few days.You loose a lot of sugar that way.Also you have to adjust sugar readings to the temp of the sap.For some stupid reason the haydrometer we buy here is set for 68 degrees sap and when the sap is real cold it reads almost 1% over what it actually is.

[Amber Gold]

I've a similar issue, just not as bad...about a 15% difference. We truck everything in and I think the biggest source of error is using the volume markings on the tank which is what we did this year. Next year we'll have a water meter.

[green4310]

I have been seeing the same thing. Yesterday I watched my RO flow @6 gpm and noted the minutes pumped @45 and came up with Approx. 270gals of 1.6% sap. Doing the math works out to around 53gal. I puled a little over 5gal of syrup which is what it should have been. 270/53. I have been looking at tank volume and guessing and grumbling for nothing.
Don't know why I could not have done this earlier. Oh well.

[SenecalsSugarHouse]

We have been boiling the sap right away. I will say that we have been going by the measurements on the tank so perhaps that would account for some of it but could that really be a 30% difference? Also my sap hydrometer is for 38 degrees but the gauge on our milk tank has been 45 or so because of the sun so does that make it higher or lower than the hydrometer reads? Lastly the syrup hydrometer is dry on the first test but then its covered in syrup for all the following tests does this affect it? Thanks for the ideas,
Dave

[allgreenmaple]

We have been boiling the sap right away. I will say that we have been going by the measurements on the tank so perhaps that would account for some of it but could that really be a 30% difference? Also my sap hydrometer is for 38 degrees but the gauge on our milk tank has been 45 or so because of the sun so does that make it higher or lower than the hydrometer reads? Lastly the syrup hydrometer is dry on the first test but then its covered in syrup for all the following tests does this affect it? Thanks for the ideas,
Dave Syrup hydrometer should be cleaned after using, syrup sticking to it will throw off your reading I would think.

[Brent]

I've never heard anyone talk about the loss due to sugar sand, but I'll bet there was a few gallons of that got tossed.

Do the rules of concentration take the sugar sand loss into account ??? (rule of 86)

[happy thoughts]

Do the rules of concentration take the sugar sand loss into account ??? (rule of 86)

I'd assume it does but you know what they say about assuming:)

I read something about the rule of 86 just the other day but can't remember where. The rule of 86 was based on a time when a reading of 65 brix was considered legal for syrup. It's still a good general rule of thumb but not extremely accurate especially now that legal syrup is at least 66 brix most places. At higher brix the sap to syrup ratio would mean a little less syrup than the rule of 86 might indicate.

If I find my source I'll post it.

[happy thoughts]

The source was an old version of the MAPLE SIRUP PRODUCERS MANUAL revised 1976 that FriarAthanasius posted a link to a few days ago.

http://www.archive.org/details/maplesirupproduc00willrich

pg 48 - (Until 1974 the standard density for maple sirup was 65.5° Brix, and sirup of this density contains 86.3 percent solids as sugar. Now that the standard density is 66.0° Brix, the percentage of sugar in a gallon of standard sirup is actually 87.2, but the traditional "Rule of 86" persists in the industry and is quite satisfactory for practical purposes.)

[buck3m]

So today as we fired up the evaporator for maybe the last time I started figuring out how close we were to actually making what our sap said we should. All together for the season we have had 7280 gallons of sap with an average sugar conent of 1.97%. So for the sake of being conservitive I figured 45 gallons to 1 gallon. That came up to 161 gallons. If I went to 1.5% sap it was 145 gallons, we only made 100! Any ideas on what we are missing. Some of the syrup may be a little heavy but with no finishing pan it is what it is. Could that be the answer or is it something else? Thanks for any ideas,
Dave

I think syrup density is one of the least likely factors in the numbers that don't add up. As you near syrup, it doesn't take much water one way or another to change the percentages a lot. How did you measure your sap?

[Gary in NH]

There is a related discussion about syrup loss in Bottling and Filtering and bulk storage of your syrup . (http://mapletrader.com/community/forumdisplay.php?f=19) The rule of 86 is simply a ratio based on the sugar content of the sap and the volume of syrup you will have after you remove a volume of water to get to 66 brix. In actuality it doesn't take into consideration filter loss, sugar sand, spillage, etc. so the rule of 86 number is an estimate and no guarantee you will end up with the amount of syrup the equation leads you to believe.