Almond production in Portugal is of great importance for the economy
of their main producing areas. However, the contamination of these nut fruits
with fungi and mycotoxins poses a significant risk to food safety and security.
This work intended to evaluate the influence of storage conditions on the microbial
andmycotoxin stability and safety of almonds throughout long-term storage.
Two almond varieties—Lauranne and Guara—were submitted to three different
storage conditions, namely, 4◦C with noncontrolled relative humidity (RH),
60% RH at 25◦C, and 70% RH at 25◦C, for a storage period of 9 months. Samples
were collected after 0, 3, 6, and 9 months of storage and analyzed for microbial
loads (aerobicmesophiles, yeasts, and molds),mold incidence and diversity,
and mycotoxin contamination. In total, 26 species were identified belonging to
6 genera: Aspergillus, Cladosporium, Fusarium, Penicillium, Paecilomyces, and
Talaromyces. For the variety Guara, mycotoxins related to Aspergillus sect. Flavi,
such as aflatoxins, averufin, versicolorin C, and norsolorinic acid, were detected
only after 9 months of storage at 70% and 60% RH. Penicillium mycotoxins, such
as quinolactacin A and roquefortine C, were also detected. For the variety Lauranne,
Penicillium mycotoxins were detected, such as citrinin, quinolactacins
A and B, roquefortines C and D, cyclopenin, cyclopenol, penitrem A, viridicatin,
and viridicatol. Mycotoxins related to Aspergillus, such as aspulvinone E,
flavoglaucin, paspalin, asperglaucide, asperphenamate, cyclo(L-Pro-L-Tyr), and
cyclo(L-Pro-L-Val), were also detected.
