Maple Syrup Production report for March 10 to 16, 2014

Previous week summary

Temperatures remained below freezing early last week.  Warming temperatures over the past weekend enabled syrup producers to begin or resume tapping trees.  A number of producers have completed all tapping and are patiently waiting to collect sap when thawing conditions occur, while others will not tap their trees until the next forecasted thaw.  Producers near Sarnia and Forest report a small sap flow occurred on Friday and Saturday, March 7 & 8, with the first light syrup produced.

The week ahead

As of Monday March 10, sap is finally flowing in the earliest southwestern Ontario sugar bushes and the first big boil will begin Tuesday March 11.  In later areas, thawing temperatures early in the week will allow syrup producers to continue tapping maple trees.  The extended weather forecast predicts that very cold freezing weather will return throughout the week into the coming weekend across much of Ontario.   Very cold nighttime temperatures will freeze up the trees again.  Maple trees should not be tapped while trees are frozen to prevent splitting of bark.

A heat shield for evaporator smokestacks

Structural wood that is exposed directly to extreme heat over extended periods can become increasingly susceptible to ignition.  In sugar houses, smokestacks require proper installation and heat shielding to prevent fire.  If in doubt, ask a qualified professional or the local fire department for advice.  Have the sugar house inspected.



Figure 1.   A homemade heat shield protects the structural wood framing from heat coming off the smokestack in this new sugar house.   Here, pieces of steel sheeting surround the smokestack as it passes through the roof (or an upper floor). Adequate separation is needed between joists and smokestack.   The heat shield must be spaced one or two inches away from wood joists by an airspace, not touching any wood. Metal heat shields should not be painted.

Preparing tubing for sap collection

Prior to the first sap flow, and where thawing temperatures prevent freezing, lateral tubing and mainlines should be wash with potable water if the sap collection system was not rinsed the previous summer or fall.  Some producers rinse sap tubing with potable water just prior to sap flow even where thorough cleaning and sanitation was completed the previous year.  Alternatively, some of the first good sap flow can be used to rinse sap lines, where the sap is discarded.



 Photo 2 & 3.   Vacuum tubing systems are commonly installed during summer or fall where the tubing may remain permanently for up to 15 years.  Equipment dealers often participate at the industry Summer Tour and fall workshops to demonstrating how to install sap tubing and educate producers in the newest technology in tubing connections and layout design.  Modern food-grade tubing materials have improvements in durability and smooth inner surfaces for ease of cleaning and sanitation.

P1040893 Blog v2

Photo 4.  Squirrels, raccoons, coyotes, and in northern areas, bears can cause chewing damage each year to sap tube collection systems, disrupting vacuum and reducing sap yield.   Inspect tubing each week to repair leaks as they occur.  With a proper permit from the Ministry of Natural Resources, hunting may be required in some years to manage damage.   Live trapping and removal is another option.

Measuring density of maple syrup

Accurate measurement of density is very important to know that maple syrup has reached the minimum density of 66 °Brix to be legally offered for sale in Ontario.  Where syrup density falls below 66 °Brix the product cannot be called maple syrup on a label.  Under-density syrup will be graded and labelled as concentrated maple sap.

Density can be measured using a hand-held refractometer, hydrotherm, hydrometer, or a portable digital density reader.  Hydrotherms may not be reliable in accuracy as previously thought, particularly when the syrup is cold.  It is important to know how to properly use density measurement equipment and how to calibrate each device prior to use.

_LWP9294edit Blog v2


Figure 5 & 6.  To give an accurate measurement, a clean hydrometer must float freely in the cylinder of test maple syrup (left) without touching the walls or bottom.  Slowly lower the hydrometer into the hot syrup (right) to prevent it from striking the bottom and potentially breaking the glass bulb.


 Figure 7.  Take the density reading where the syrup level meets the centre of the glass stem, not at the edges.  Here, the uncorrected density reads 66.5 degrees Brix.  For hydrometers, measure the temperature of the test syrup and refer to a density correction table to either add or subtract degrees Brix from the observed hydrometer reading.  Syrup can cool surprisingly fast after leaving the evaporator.  Identical density readings from two different devices will provide confidence that the readings are accurate.










Figure 8 & 9.  Portable digital density readers are becoming more common, although are expensive.  Place two or three drops of syrup to be tested to just cover the glass, then close the cover.  Don’t over-fill the dish, a common mistake.  Wait a few seconds to allow the syrup and dish temperatures to equilibrate before measuring the density.  Calibrate the instrument prior to boiling each sap run using distilled water to zero the reading.


Figure 10.  A refractometer is used to measure syrup density.  Bright natural light from a large window will give a clear visual reading.  Calibration oil that has a known density can be purchased from maple equipment dealers to ensure the refractometer is measuring syrup density accurately.

This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply