Abstract The sun-dried pear of S. Bartolomeu (Pyrus
communis L. var. S. Bartolomeu) is a traditional sweet food
product of unique elastic properties and reddish brown
colour. Alternative drying methodologies to replace the
traditional open air sun-drying procedure are under development,
namely the use of greenhouses with and without
air convection and a hot air tunnel. To test whether the
Maillard reactions can contribute to the colour of this traditional
product, the profiles of free and bound amino acids
constituents of the pulp of fresh pears as well as pears
processed according to different drying methodologies
were evaluated. Also, the occurrence of furosine, carboxymethyllysine
(CML) and carboxyethyllysine (CEL),
indicative of Maillard reaction, was diagnosed and quantified.
The drying of the pears affects the free amino acid
profile, increasing proline content and decreasing aspartic
and glutamic acids. Although the proteic amino acid profile
was not significantly modified with the drying process, a
loss of the relative content of Lys was observed. This loss
was related with the increase in the amount of furosine,
CML and CEL formed during the drying of the fruits.
Although all drying methods tested promoted the increase
in the amount of CML, CEL and furosine, this increase was
higher in the case of the traditional sun-drying and greenhouse
processing, where the fruits presented reddish brown