Biology Reference
In-Depth Information
29.1
Introduction
In recent years, mycotoxins have gained increasing importance in public health.
Nowadays, in addition to aflatoxins and ochratoxins, other mycotoxins such as
patulin are considered of relevant interest. This mycotoxin is produced by several
fungal species:
Aspergillus
spp.,
A. clavatus
,
Penicillium expansum
,
P. clavigerum
,
P
.
griseofulvum
,
Byssoclamis
spp.,
B. nivea
, and
B. fulva
. It is considered neuro-
toxic, hembriotoxic, and teratogenic (Dombrink-Kurtzman and Balckburn
2005
). It
has been classified by the International Agency for the Research on Cancer as
category 3, even though its carcinogenic activity on animal models has been
demonstrated (Cunha et al.
2009
). The law limits of patulin in foodstuffs have
been established only for fruits such as apples and apple-based products (Commis-
sion Regulation
1881
/2006). However, patulin has been detected in many other
food items: bread and baked products and meat products (L´pez-D´az et al.
1996
;
Erdogan et al.
2003
). Furthermore, toxin-producing strains can be used as natural
starter cultures or can be present in cheese manufacturing, seasoning, and ripening
environments; however, few data are available for dairy products (L´pez-D´az et al.
1996
; Erdogan et al.
2003
; Kokkonen et al.
2005
).
The aim of this work is the identification and quantification of patulin in a
traditional, hand-made, semihard cheese named “Toma Piemontese.” Such a type
of cheese has been considered because it is generally manufactured and stored with
procedures and in environments not always carefully controlled. All samples were
acquired from the retail trade; some of them showed defects and mold growth on the
surface.
29.2 Materials and Methods
The study has considered 25 semihard cheeses (inner parts and rind) produced with
raw cow milk with a cheese-making technique usually applied for “Toma
Piemontese.” The milk is coagulated by the addition of bovine liquid rennet at
temperatures between 32 and 35
C. The curd is cut twice to produce granules about
the size of maize grains. After draining, the curd is put in molds, pressed for
approximately 36 h, and then dry salted or salted in brine.
The identification and quantification of patulin were performed using an HPLC
apparatus.
Patulin standards were purchased from Fluka (Buchs, Switzerland). All solvents
were of HPLC grade (Merck, Darmstad, Germany). The water was filtered by a
MilliQ System (Millipore, Billerica, MA, USA). For extraction and quantification,
the protocol of Kokkonen et al. (
2005
) was used. The confirmation of the results
