Making birch syrup

[governor]

I was just wondering if the birch sap can handle a full boil up to 45 brix? All of my density equipment, (Hydrometers, Refractometers, Hydrotherm) Stop reading around 12-18 or start reading around 45. I wanted to pull the sap off the evaporator at a safe brix to not scorch it and transfer it to my double boiler set up. So if I can take it till it starts to read at 45 that would be ideal but I don't want to scorch it after all of this effort so far. We have about 120 trees tapped and I think I'll finally have enough sap tonight in a 24 hour period to justify cranking up the RO. Boiling .4 sap sucks!

.4 sap is not worth processing period! we stop at .7 max and that makes really strong dark syrup.

[governor]

I was just wondering if the birch sap can handle a full boil up to 45 brix? All of my density equipment, (Hydrometers, Refractometers, Hydrotherm) Stop reading around 12-18 or start reading around 45. I wanted to pull the sap off the evaporator at a safe brix to not scorch it and transfer it to my double boiler set up. So if I can take it till it starts to read at 45 that would be ideal but I don't want to scorch it after all of this effort so far. We have about 120 trees tapped and I think I'll finally have enough sap tonight in a 24 hour period to justify cranking up the RO. Boiling .4 sap sucks!

.4 sap is not worth processing period! we stop at .7 max and that makes really strong dark syrup.

[BC Birch Tapper]

Ours is about 0.5 & yes it it is strong & dark but the chefs love it & so do we.
We sell ours for $88 per litre

[MillbrookMaple]

The way it is done in alaska by the "expert's expert" is on 10-12% sap through an RO it is brought to 224*F and drawn off at 67 Brix..

A couple more questions. Do you boil on a regular style evaporator or is it a steam evaporator? I am boiling this on a small 2x4 wood fired evaporator that belongs to my friend since after the RO I expect to only have about 20-30 gallons of sap. We have about 100 taps that we are running and hopefully will be able to RO the sap every other day and boil. .5 is what we got last night when we collected and the trees really have just started to run. Does the sugar content and sap volume climb during the beginning of the season?
Boiling point in our location runs between 208-210 range at our elevation. Based on sea-level are you drawing off at 12 degrees above boiling point and that is about 67 Brix? Maple draws off around 7 above boiling for 66.5 Brix. Lastly what causes the burning/scorching? Is it just the temp burning the sap or is it the sugar sand, Nitre, or what ever birch syrup makers call it precipitating out of solution, settling on the pan, and burning in flakes?
I made some very dark syrup (Birch) on the stove in a double boiler a couple of nights last week and found that I liked the syrup at around 70 Brix and everyone though it tasted like a mix of caramel and molasses. I also made some around 60 and didn't like it as much. I would imagine that just like Maple the RO should help lighten the syrup some and temper the flavor slightly. Thanks for the input everyone!

[Snowy Pass Maple]

MillbrookMaple -

I'm across the river from you (near Millbrook) also tapping some birch. How are you keeping the sap cold? Temperatures have been in the 70s this week which is way above normal and I'm very worried about spoilage.

I'm collecting out of buckets every 12 hours. I've been running them through a 1 micron filter and UV lamp into storage; aiming to then get them through RO within 12-24 hours and then into the fridge to cool down. I have been throwing blocks of ice in jugs to try to keep sap cool, but can't really get it below 60. Not sure this is going to work out well until things cool down a bit!

[BC Birch Tapper]

we use a drop flue 2x6 & pull off at around 25 deg brix & finish on a double boiler
The sugars change as the season progresses but the % stays the same. Initially it has a bit of sucrose but that falls out as the sesason progresses. The main sugars are fructose & glucose which have a lower bioling temp than sucrose. progresses. Birch has about 8 % micronutrients as opposed to about 2 % for maple. The end of season syrup is better for blends or some other application. Initially one can run at temps just over 100 deg C but as the sugars concentrate when you're finishing you have to drop the temp lower or run the risk of burning or scorching it.
You will have to filter out the sugar sand or nitre or it will impact the taste & the excess buildup on the pan can cause bumping. We clean our pans every moring to remove the dark sugar build up on the pan. We finish ours to about 60 deg brix
Any time you can remove water without heating results in a lighter tasting & lighter coloured syrup

[MillbrookMaple]

MillbrookMaple -

I'm across the river from you (near Millbrook) also tapping some birch. How are you keeping the sap cold? Temperatures have been in the 70s this week which is way above normal and I'm very worried about spoilage.

I'm collecting out of buckets every 12 hours. I've been running them through a 1 micron filter and UV lamp into storage; aiming to then get them through RO within 12-24 hours and then into the fridge to cool down. I have been throwing blocks of ice in jugs to try to keep sap cool, but can't really get it below 60. Not sure this is going to work out well until things cool down a bit!

I am actually north west of you in Margaretville, NY in the Catskills. My farm is on Millbrook Rd. It has been too warm but 24 hours seem to be ok for collecting. I dumped a bunch of sap last week that had been multiple days sap since I didn't have enough to do anything with I just let it sit. It gets cloudy and yeast smelling when it spoils so I can tell when I dump the buckets. I collected last night in my truck tank and plan to go back out at 10 this morning and collect again RO and boil. I am hoping that the weather stays a little more reasonable for the rest of the season so we don't have to worry about spoilling so much. Our forcast up here at 2000 feet is for about 20 degrees for Monday night. I checked my sugar maples and they are still looking ok so I'm cleaning lines and tanks and the releaser and hoping to make more maple syrup this year too. This will make things tough for the birch but we have seperate equipment for the birch so at least I don't have to worry about cleaning everything each time. (tanks, evaporator, Ro) It will be more of a process of loosing a buch of sleep

[Snowy Pass Maple]

I had one bucket I missed in the AM collection yesterday - and by PM, in 24 hours, yea, it was yeasty and cloudy. Otherwise the sap is really clear when I collect - I think the problem I'm having is chilling it while processing on the RO and getting it down to cold storage fast enough.

I boiled a sample of concentrate down and while it was nicely sweet without as intense a fruity/tart taste that comes later in the run, there is also some other taste that is kind of bitter. I'm guessing either it's the fact that I didn't filter this small sample and it's full of mineral content, or it started to spoil between collection and time getting through RO into the fridge. Will do some more tests today!

[MillbrookMaple]

It's pobably just like maple. Sugar sand in Maple leaves a bitter after taste so it should be worse with Birch. We are working on modifications to cut down our full bank filter press to a 2 plate press. If I didn't I would probably loose all my birch syrup in the press. Hopefully I will have some to try by tonight. I don't know if this would work for you, but what about boiling the concentrate right out of the RO before the cold storage? If it gets boiled it would be pasturized thus not likely to spoil for a few days.(as long as you put it a clean sealed container) You have to let it cool, then put it in the fridge then re-heat, but if you need to have multiple days of sap to boil it might keep better.

[Snowy Pass Maple]

It's pobably just like maple. Sugar sand in Maple leaves a bitter after taste so it should be worse with Birch. We are working on modifications to cut down our full bank filter press to a 2 plate press. If I didn't I would probably loose all my birch syrup in the press. Hopefully I will have some to try by tonight. I don't know if this would work for you, but what about boiling the concentrate right out of the RO before the cold storage? If it gets boiled it would be pasturized thus not likely to spoil for a few days.(as long as you put it a clean sealed container) You have to let it cool, then put it in the fridge then re-heat, but if you need to have multiple days of sap to boil it might keep better.

My problem has been more just keeping up with the collection through the RO - for maple, it worked great but my birch taps are overwhelming me! This is a homebuilt unit so only a few gallons per hour of water removal - I am trying a nanofiltration membrane today and it seems to be doing a lot better so far.

For the batch I'm running now, the sap was just from overnight - 15 hours since last collection. Ran through the UV, and then chilled down to 52 F using ice blocks. About the best I can do in this weather so we'll see how it turns out. I also put in a new filter and checked that my UV tube is clean. I'm hoping that the UV would help - I have it oversized considerably relative to my flowrate through it and the birch sap goes in at such a low concentration that the sugars should be less of a concern than with maple sap.

Collecting sap today, I noticed it's still clear in the buckets, but all has a faint greenish/yellow tint to it. I get a few bubbles when pouring it but none of the foam I saw from a bucket that I forgot for 24 hours. All of the sap has a similar faint smell to it - not cloudy, but a definite smell that seems unique to birch. I could pick this up more in the RO concentrate tank after it concentrates it.

I'm reducing enough to filter a bit on the stove through a pre-filter and just see if any of this early stuff will be usable or not. I am also looking forward to some cooler temps - although it'll be interesting to see how the trees react - I expect they'll shut down for a couple days, and hopefully they aren't racing to bud. I can't see any yet.