In my copy of the North American Maple Syrup Producers Manual, it says
that finished maple syrup should be at 65.5 brix which is close to the same
as saying that it is 65.5 percent sugar. Above 65.5, sugar will precipitate
forming crystals at the bottom of its container. The sugar will continue to
precipitate until the brix reaches 65.5 again. If your finished syrup is
less than 65.5, it is susceptible to mold. If your 65.5 brix syrup molds,
it is because it underwent a change in temperature so that water evaporated
out of the syrup, condensed at the cap and dropped to the top of the syrup;
then, at the top of the syrup, it is no longer 65.5 and it is susceptible to
mold.
If your maple syrup molds, skim off the mold and heat the syrup to at
least 180 degrees and re-bottle it. Mold that forms atop properly
manufactured sugar-containing products are of non-lethal species - in other
words, it won't hurt you (at least, that is what 'the book' says).
In grammar school we are taught that water boils at 212 degrees. What
'the book' should say is, "Water boils at 212 degrees at sea level at 30.0
inches of mercury." At my altitude, water boils at 210 degrees at 30.0
inches of mercury. Many beginners boil their syrup to 7 degrees above the
boiling temperature of water but they need to test every day and again if a
weather front blows in. It is advisable to remember that water has a
(temperature) range of boiling and that your reading should be taken after
it boils for a few minutes.
The most accurate method of determining when your maple syrup is
finished is to test it with a refractometer. Refractometers are expensive
with the least expensive selling near $100. The next best method is to use
a hydrotherm which measures density at any temperature and the least
expensive method is a hydrometer which measures density at a specific
temperature. Syrup hydrometers cost around $15 and you'll need a hydrometer
cup which might set you back between $30 and $50, depending upon who you buy
it from (Many people make their own). I DO NOT SELL MAPLE SUPPLIES but, if
you want to buy items, I can turn you onto dealers.
Jim Fruth
Brambleberry Farm
Pequot Lakes, MN 56472
For jams, jellies & syrups:
www.bberryfarm.com
(877)265-6856 [Store]
(218)831-7018 [My Cell]
[NAFEX] Maple facts and more,
Jim Fruth, 02/26/2008