Coordinated through the Ontario Maple Syrup Producers Association,
68 maple syrup producers sent samples proportional to the
volume of production in each of the 11อmaple-syrup producing districts
in Ontario which span an area of ~250,000 km2. The samples from
each producer comprised 6 250 ml containers of syrup (48 medium
grade, 9 amber, 8 light and 3 ungraded). Samples were blind-coded
for producer locationwith information on factors thought to predispose
samples tomold contamination (e.g., cold packing, container type, reverse
osmosis, wood versus oil heat, preheating containers). The samples
were received at Carleton University over a three week period from
the annual production in the spring of 2014 shipped via Canada Post
by the producers. Samples were generally received within two days
and were stored at room temperature in their original boxes until
processed.