THERMAL CHARACTERIZATION OF AVOCADO (Persea

THERMAL CHARACTERIZATION OF AVOCADO (Persea americana) SEED UNDER
OXIDATIVE ATMOSPHERE
a
a
a
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Michele B. I. Ambrósio , Nathassia G. Selinga , Raquel C. Lima , Ivo, M. Demiate , Marco A.
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b
a,c
S.C. Filho , Egon Schnitzler . Luiz G. Lacerda
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Department of Health and Biology Sciences, Universidade Positivo, R. Prof. Pedro Viriato
Parigot de Souza, 5300, CEP 81.280-330 Curitiba, PR, Brazil
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Food Engineering Division. Universidade Estadual de Ponta Grossa. Av. Carlos Cavalcanti,
4748. CEP 84030-900 Ponta Grossa. PR. Brazil
c
Industrial Biotechnology MSc Program. Universidade Positivo, R. Prof. Pedro Viriato Parigot
de Souza, 5300, CEP 81.280-330 Curitiba, PR, Brazil
Avocado is a tree native to Central Mexico. It is expected the world production will reach 4,7
MTon in 2012. The fruit seeds from avocado are a waste product in the pulp and oil production
and represent about 12 % of the fruit weight. The seed is very rich in starch and fiber thus it can
be widely used as food ingredient. In this research, Thermal analyses: TG (Thermogravimetry),
DTA (Differential Thermal Analysis) and DSC (Differential Scanning Calorimetry) curves were
recorded using a Shimadzu TG 60 and DSC 60, with synthetic air flowing at 100 mL/min., and a
heating rate of 10°C/min. and with mass samples of about 6 mg. Alumina open sample holder
and aluminum sealed crucibles were used for TG/DTA and DSC, respectively. TG showed a
moisture loss of 8.12%, total mass loss of 91.97% and the first thermal degradation was
detected at 288.20°C (on-set). DTA showed first oxidative peak at 339.67°C and a second
degradation peak at 493.87°C. DSC endothermic profile curve is related to melting event of
starch presented in sample. The enthalpy required for the event was estimated as 154.20J/g
and melting point occurred at 146.76°C. TG is used to measure the mass loss either as a
function of time (isothermal) or dynamic temperature and controlled atmosphere. Endothermic
and exothermic changes in a DSC curve indicate events or reactions such as gelatinization and
melting. Thermal analysis regards to methods for matter characterization and can be used in
food as a useful analytical method.