Author(s):
Tavaria, F. K. 
; Ferreira, A. C. Silva ; Malcata, F. Xavier
Date: 2004
Persistent ID: http://hdl.handle.net/10400.14/6698
Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
Subject(s): Solid phase microextraction; Dairy foods; Gas chromatography-mass spectroscopy; Sensory analysis
Description
Serra da Estrela cheese is an artisanal cheese manufactured
from raw ewe’s milk coagulated with Cynara
cardunculus; it is highly appreciated for its unique flavor
and bouquet. This research effort focused on a
search for the molecules responsible for those organoleptic
characteristics. Eighty cheeses manufactured in
4 dairies located in the Appe´lation d’Origine Protege´e
region of Serra da Estrela, Portugal, were thus assayed
for volatiles, in an attempt to characterize their odorous
profile. Cheeses were analyzed from the time of manufacture
up to 180 d of ripening. The volatile fraction
was assayed by solid phase microextraction-gas chromatography/
mass spectroscopy, and several compounds
belonging to different chemical groups (e.g.,
fatty acids, esters, carbonyl compounds, pyrazines, and
sulfur compounds) were detected in that traditional
cheese. Among these, free fatty acids (FFA) were quantitatively
the dominant family present. Furthermore,
sensory descriptors for the typical aroma of this cheese
included acidic, sweaty, and sheepy-like. Acetic, isobutyric,
and isovaleric acids increased in concentration
during the ripening process up to 90 d, and remained
constant thereafter. Preliminary sensory analysis was
performed by addition of the major FFA to an unripened
cheese matrix; results showed that they could successfully
be used as ripening indicators for this cheese. Such
key molecules may thus be used to monitor ripening,
and hence find the optimal consumption time for this
gourmet dairy product.
(Key words: solid phase microextraction, dairy foods,
gas chromatography-mass spectroscopy, sensory
analysis)
