Acer saccharum Marshall - syn.Acer barbatum auct. - Sapindaceae - sugar maple, **Zucker-Ahorn**

Deciduous tree, up tp 25-35m tall, native to the eastern North America; leaves up to 20cm long, with 3-5 palmate lobes; flowers in corymbs of five to 10 together, yellow-green, without petals; fruit a double samara with two winged seeds, the seeds are globose, 7-10mm in diameter, the wing 2-3cm long. \\
"This tree is a main component of the Eastern U.S. hardwood forest and is one of the trees which is most responsible for giving New England its reputation for spectacular fall color." \\
[[http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=h240]] \\
[[http://en.wikipedia.org/wiki/Acer_saccharum]]

"...by the time European settlers arrived in North America, native Americans had already learned to slash the bark of maple trees in late winter or early spring, collect the near-clear sap that came out, and boil the sap into a thick, sweet product... of the thirteen species of the genus Acer in North America, the sugar maple (A. saccharum), the black maple (A. nigrum), and the red maple (A. rubrum) provide most of the sap for syrup production. There are two reasons for this. First, the sugar content of their sap is typically higher than other species, at 2.0-2.5%. Second, the annual growth spurt of these species occurs later in the spring than other maple species, increasing the length of the sap-collecting season... it takes the combustion of 65 L of natural gas to generate about 20 mL of syrup - about 1.5 tablespoons. Clearly, the production of significant volumes of syrup is an energy-intensive process." \\
[The chemical composition of maple syrup. Ball DW, Journal of Chemical Education, Vol.84(10), 2007, 1647] \\
[[http://chefcristysrawfoods.com/images/maple73.pdf]]

"Portions of a distinctively flavored commercial maple sirup were heated by autoclaving at 15 psig (250°F) for 1.5 and 4 hr. A GLC flavor profile of the treated and untreated sirups showed that 25 components in their flavor fractions changed in relative amounts. In the light colored original sirup, acetol and compounds related to lignin (vanillin, syringaldehyde, dihydroconiferyl alcohol) predominated. As the sirup was heated, carbohydrate breakdown products began to appear and then to predominate (acetol, furanones, cyclotene, and HMF). As the carbohydrate degradation products increased the sirup darkened in color and became acrid in flavor; at this point vanillin began to decrease." \\
[Effect of heat on the flavoring components of maple sirup. Underwood, J. C., Journal of food science Vol.36(2), 1971, 228-230]

| {{:hdmf.jpg| furaneol}} \\ furaneol | {{:sotolon.jpg| sotolon}} \\ sugar furanone (sotolon) | {{:guaiacol.jpg| guaiacol}} \\ guaiacol | {{:vanillin.jpg| vanillin}} \\ vanillin |


"A base syrup formulation containing nonvolatile flavor compounds was used to systematically evaluate the sensory contributions of selected volatile compounds (furaneol, 2,5-dimethyl-4-hydroxy-3(2H)-furanone; sugar furanone, 4,5-dimethyl-3-hydroxy-2(5H)-furanone; guaiacol, 2-methoxy phenol; vanillin, 4-hydroxy-3-methoxy-benzaldehyde) to maple syrup flavor. Descriptive sensory panels showed that all compounds contributed to maple flavor intensity, but sugar furanone was an exceptionally important determinant. Medium and dark amber syrups contained generally higher concentrations of the selected flavor compounds than the light amber syrup. 5′-Inosine monophosphate was tentatively identified in maple syrup by HPLC analysis, and was found to contribute important taste characteristics to maple syrup. Consumer studies showed that more flavorful, darker grade A syrups were preferred over light amber grade A syrup." \\
[Contributions of selected flavor compounds to the sensory properties of maple syrup. Belford, A. L., R. C. Lindsay, and S. C. Ridley., Journal of sensory studies Vol.6(2), 1991, 101-118]

Total and individual concentrations and distribution of pyrazine compounds (2-methylpyrazine, 2,5-
dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethylpyrazine, 2,3-dimethylpyrazine, trimethylpyrazine, 2-ethyl-3-methylpyrazine, tetramethylpyrazine, 2-ethyl-5-methylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-3,5-dimethylpyrazine and 3-ethyl-2,5-dimethylpyrazine) in different maple syrup grades have shown to significantly influence the perceived maple flavor and taste of the syrup. \\
"Tehe identified... 2,3-dimethyl-, 2,5-dimethyl- and 2-ethyl-3-methyl- pyrazines migth play some role in the taste preference of maple syrup; this hypothesis needs to be developed further." \\
[Akochi-Koblé, Emmanuel. "The Formation of Pyrazine Compounds and their Contribution to Maple Syrup Flavor."  (1995)]

{{:acer_barbatum.jpg?600}} \\
Sargent, C.S., The Silva of North America, vol.2, t.91 (1898) [C.E.Faxon] \\
[[http://plantgenera.org/species.php?id_species=10262]]