Jutaicica is the Amazonian colloquial name for the forest product commercially
known as ‘copal do Brasil’, a resin that exudes from the trunk of Hymenaea L.
(Fabaceae) trees. Species of Hymenaea are distributed in lowland tropical evergreen
rainforest in Santarém region, state of Pará. Spectroscopic and thermoanalytical
techniques are used in order to characterize and differentiate resin samples.
Although copal had been used for centuries in varnish manufacture, it has been
completely replaced by synthetic resin in recent decades. This study highlights the
need of better understanding and more accurate information regarding ‘copal do
Brasil’ occurrence and characterization. Historically, Brazilian domestic market was
mainly supplied by the state of Pará, with the resin collected in Santarém and
surroundings. Samples from the two main botanical sources, Hymenaea courbaril L.
and Hymenaea parvifolia Huber trees were collected along non-flooded land riverside
of Tapajós and Curua-Una rivers and their tributaries. Resin batches from the two
species can be visually differentiated by naked eye. The H. courbaril material is
predominantly clear and light-colored while H. parvifolia ranges from cloudier to
darker. Spectra and thermal curves show different patterns allowing a distinction
between the two species. The thermal analysis suggests a lower content of
polymerized material in H. parvifolia resin. The infrared and carbon 13 nuclear
magnetic resonance spectroscopy show homogeneity among the H. courbaril resin
samples, but also distinguishes this botanical specie from H. parvifolia resins through
the absorption peaks intensity due to olefinic and oxygenated groups.
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