We have been making Birch Syrup off and on for about 10 years. A few years back a bunch of producers around the world and met at conference hosted by Cornell at Paul Smiths in the Adirondacks. Though we didn't come up any standards I feel that the majority of the producers there take their syrup to the same brix as maple. That is how we do it and we have a market for it with return customers. What was established that their are many ways to use birch sap and syrup and you just have to look at it as totally different than maple.
Many of the producers will separate the syrup into first run, Mid run, and late run to grade the syrup.
I want to reiterate what some have posted.
Low sugar content. .2%-.7% is where our raw sap ranges. I would not suggest doing it without and RO. The amount of fuel needed to make a gallon is not worth the environmental impact. Also just like maple the longer you boil the more it darkens and it is a potent flavor regardless.
Again... It is not table syrup... It is not maple syrup. Do not put it on pancakes. It is an ingredient. Don't just take a big swig of it as well. People use vanilla extract to make things taste awesome all the time. I dare you to take a spoonful of vanilla extract and say you like the flavor. Our favorite recipe is to make glaze for Salmon and grill it. (Birch syrup, Garlic, Soy Sauce, lemon juice) but as others said. BBQ sauce and pork glazes are great uses. It is also good in baked products. It is unique flavor and has to be appreciated in the right way.
I have customers that own restaurants that use about a quart a month for signature dishes. We sell it for $150 a half gallon shipped for these customers. For retail we sell it for $30 for an 8oz bottle shipped. We made 26 gallons a few years ago and have sold out. (400 taps that year)
Since maple season was a bust and we were out of birch we did tap a few weeks ago when if finally warmed up but we went from snow on the ground to 89 degrees in one week and we managed to make only 4 gallons and are pulling the plug because the yeast growth is very fast and the sap is spoiling. This was an odd spring and now just looking forward to next year for our syrup adventures.
We boil ours right down to a point from finished right in the evaporator. We try to get the sap to 5-8% with the RO. We also don't lay back on the heat unless it gets too foamy. We have had no success with using pipeline in the past and do all of our birch on buckets. A tap can run anywhere from 1-5+ gallons a day.
I'm not sure if this answers the original questions but I felt I needed to chime in just for the fact that so many dislike the product and probably have no idea how to use it. A simple spoonful into the mouth will haunt you all day so stop trying it like that.
If you have a bunch of birch trees and an RO I suggest people try it if they are interested. We spend so much money on equipment for maple it would be nice to have other uses for it. Also if someone has no maple trees but lots of birch, it gives them something they can do in their woods. that is a fun springtime project.
Side note: We had some friends test making sycamore syrup this year and I'll tell you maple syrup people will enjoy that syrup's flavor. The strange spring made us unsure when the season is for sycamore but more tests will be run in the coming years.