Capsaicins, present in most hot sauces and salsas, are responsible for the
“hot” sensation in many spicy foods. At high doses, capsaicins cause
significant discomfort upon contact with the sensitive tissues of the
mouth and throat of mammals. By applying a capsaicin containing paste to
the outside of maple tree sap collection tubing, operators hope to
minimize rodent (primarily red squirrel, Tamiasciurus hudsonicus) gnawing
damage to the tubing. However, some operators and sap processors have
expressed concern regarding the potential migration of capsaicins through
the tubing and into the tree sap, leading to contaminated maple syrup. To
address these concerns, we filled a variety of new and used sap collection
tubing with maple sap, plugged the ends, and coated the tubing with a
commercially available capsaicin-based rodent repellent paste. Following
storage, the contents of the tubes were carefully removed and subjected to
a solid-phase extraction clean-up process. Capsaicins in the sap were then
quantified by high performance liquid chromatography/fluorescence
detection. Results indicate that polyethylene tubing was more resistant to
capsaicins migration than was polyvinyl tubing. While capsaicins were
detected in the sap, the predicted levels in syrup would be below the
human taste threshold.
DESCRIPTORS: capsaicin-; contaminants-; contamination-; flavour-compounds; maple-syrup;
pest-control; plant-pests; plant-products; polyethylene-; rodent-control;
rodent-repellents; sap-; translocation-