Want to learn how maple syrup is made? Then follow Julia to the sugar bush. Our almost three and a half year old is turning into quite the little hiker these days.
On the hike we'll talk about signs of Spring and before long we'll spy the red buckets that dot the low spot on the Prairie Trail where the trees have been tapped this season.
Tapping maple trees only takes about 10% of the tree's sap and can be done year after year in healthy trees.
What trees should you pick?
They should be at least 40 years old and 18-24 inches in diameter
How much sap can you get from one tree in a season? It varies, from 10-20 gallons.
But I'm getting ahead of myself here. Let's go back to where it all starts...the previous year. When the botany terms I haven't thought of since college come back to me like...
Photosynthesis (the process of converting light energy to chemical energy and storing it in the bonds of sugar)
And Chlorophyll (the molecule that absorbs the sunlight and
turns into a sugar (sap), otherwise known the plant's fuel that then travels through the veins in the leaves.)
In the Fall when the trees are dropping their leaves and preparing for winter, the sugar (sap) travels deep down into the tree's roots until the Spring thaw gets it moving again.
We watch patiently for signs of when the sap is ready to start flowing.
1) the temperature gets above freezing during the day, but dips below freezing at night (anytime the temp is above freezing for more than 36 hours in a row the flow stops)
2) When the woodpeckers start pecking at the trees. Why you ask? Because when the sap starts flowing, it awakens the bugs that were hibernating behind the bark all winter. Woodpeckers can hear them moving. Pretty amazing don't you think?
I'm sure there are other ways to tell when the sap is about to run, but these are the two I know of.
This year the sap started to run on March 19th. It will be interesting to track the variation in start times in our Nature 365 Journal.
To collect the sap a small hole is drilled into the tree in order to collect the sap using a five gallon bucket and some special tubing that comes from a supply company that our park orders from. A lid is secured on top to keep out debris and to deter animals.
On the evening we hiked to the sugar bush the buckets were 1/3 of the way full. I'm pretty sure they had been emptied in the morning.
See how clear the sap is? It looks and tastes pretty much like water.
That's because it is mostly water. It's only 3% sugar.
By the time it's made into syrup it will be 66% sugar. But I'm getting ahead of myself again.
While we're out in the sugar bush I like to tell the story of how the Native Americans discovered maple syrup. The story goes that a warrior got up one morning, retreived his hatchet from the tree he had stuck it into the night before and left a gash in the tree. He went on his merry way and all morning and afternoon sap dripped out of the tree into a birchbark basket that happened to be positioned below. A woman saw what she thought was water in the basket and added it to their evening meal. When the warrior asked what made the stew so sweet they figured out that it wasn't water she had added but sap from the tree that had cooked down over the fire all day, getting sweeter by the hour.
Speaking of sweet, our little tour guide is ready to take everyone back to the syrup shack and see how we cook sap the modern way. Strap on your pack and follow Julia....
(If only the kids hiked that fast in real life!)
At the Syrup Shack the sap is transferred from the Gator tank back into five gallon buckets.
When this photo was taken on March 20th there wasn't a whole lot of sap yet...especially compared to last year.
Inside the shack is an evaporator where the sap is poured to begin the cooking process. This evaporator is fueled by wood. The sap cooks for hours and hours (18+ usually) before it is transferred to a finishing pan that is propane so the temperature can be more precise.
This is the point that I like to point out just how much sap it takes to make syrup. See that five gallon bucket? It will yield 2 ounces of syrup. Now you know why you pay $9 for a bottle of real maple syrup!
Sap is cooked to about 219 degrees...usually. Air pressure will affect when water boils so a barameter is used to make sure the syrup is cooked correctly.
The final test of whether the syrup is cooked enough is to test its density. This is done using a hydrometer. A little syrup is scooped into this metal tube (there are two red lines on the hydrometer that the edge of the tube should fall in the middle of.) If the hydrometer sinks too low it means that the syrup is too thin and could ferment also the sugar content isn't high enough so the syrup won't taste as good.
If the hydrometer floats too high then it means that the syrup is too thick and it will chrystalize. I think you can solve this problem by transferring some syrup from the evaporating pan, but I'm not certain. We are not involved in the actual production - only the education side of it.
When the syrup is at the proper temperature it is run through a filter (think giant coffee filter) to remove debris. A canner is used to preserve the syrup safely and then it is poured into the little bottles you can see here.
Time will tell how long our season lasts this year since it started a little later than usual. There are some years when the trees don't share any of their sap. If it warms up too fast and never gets below freezing again, then the buds will come out on the tree and the window on syruping is closed. Syrup made after the buds appear tastes like burnt bacon. So I'm told.
And that folks is the last drop of knowledge I have on how to make maple syrup!