Percorrer por autor "Jelassi, Arij"
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- Effect of different storage conditions on the stability and safety of almondsPublication . Rodrigues, Paula; Jelassi, Arij; Kanoun, Elifa; Sulyok, Michael; Correia, Paula; Ramalhosa, Elsa; Pereira, ErmelindaAlmond 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.
- Effect of different storage conditions on the stability and safety of almondsPublication . Rodrigues, Paula; Jelassi, Arij; Kanoun, Elifa; Sulyok, Michael; Correia, Paula; Ramalhosa, Elsa; Pereira, ErmelindaAlmond 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 and mycotoxin stability and safety of almonds throughout long-term storage. Two almond varieties-Lauranne and Guara-were submitted to three different storage conditions, namely, 4 degrees C with noncontrolled relative humidity (RH), 60% RH at 25 degrees C, and 70% RH at 25 degrees 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 (aerobic mesophiles, 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. Practical Application(Optional, for JFS Research Articles ONLY) The quality of almonds depends on the storage period and the RH and temperature at which they are stored. Storage of almonds at 60% RH at 25 degrees C is a good storage condition to maintain the stability and safety of nuts in terms of microbial and mycotoxin contaminations.
- Effect of relative humidity on the quality and safety of peeled almond kernels (Prunus dulcis Mill.) during simulated maritime transport/storagePublication . Fernandes, Luana; Graeff, Francieli; Jelassi, Arij; Sulyok, Michael; Garcia, Carolina; Rodrigues, Nuno; Pereira, J.A.; Bento, Albino; Kanoun, Alifa; Rodrigues, Paula; Pereira, Ermelinda; Ramalhosa, ElsaLong-term transport and storage of peeled almonds under unsuitable conditions may cause the product’s rejection. To get knowledge in this topic, peeled almonds were stored at 25◦C and 60, 70, and 80% relative humidity (RH). The maintenance of high RH (80%) caused some visual defects after 4 months. Even though the 60, 70, and 80% RH did not clearly affect the production of primary and secondary products formed in the lipid oxidation during the 6 months of storage, sometimes an increase in the values of the specific extinction at the wavelength of 268 nm (K268) was observed at 80% RH, suggesting the occurrence to some extent of secondary oxidation. Concerning microbial counts, the almonds stored at 60 and 70% RH presented a satisfactory microbial quality until 6 months; however, at 80% RH, the mold counts were higher than the reference values after 2 months. Several mycotoxins were detected at low levels, including aflatoxins B1 and G1, although some showed higher amounts at 80% RH. In general, it is recommended that almond producers and industrials should consider the use of low RH (< 80%) for maritime transport and long-term storage of almond kernels.
- Effect of relative humidity on the quality and safety of peeled almond kernels (Prunus dulcis Mill.) during simulated maritime transport/storagePublication . Fernandes, Luana; Graeff, Francieli; Jelassi, Arij; Sulyok, Michael; Garcia, Carolina; Rodrigues, Nuno; Pereira, J.A.; Bento, Albino; Kanoun, Alifa; Rodrigues, Paula; Pereira, Ermelinda; Ramalhosa, ElsaLong-term transport and storage of peeled almonds under unsuitable conditions may cause the product's rejection. To get knowledge in this topic, peeled almonds were stored at 25 degrees C and 60, 70, and 80% relative humidity (RH). The maintenance of high RH (80%) caused some visual defects after 4 months. Even though the 60, 70, and 80% RH did not clearly affect the production of primary and secondary products formed in the lipid oxidation during the 6 months of storage, sometimes an increase in the values of the specific extinction at the wavelength of 268 nm (K-268) was observed at 80% RH, suggesting the occurrence to some extent of secondary oxidation. Concerning microbial counts, the almonds stored at 60 and 70% RH presented a satisfactory microbial quality until 6 months; however, at 80% RH, the mold counts were higher than the reference values after 2 months. Several mycotoxins were detected at low levels, including aflatoxins B1 and G1, although some showed higher amounts at 80% RH. In general, it is recommended that almond producers and industrials should consider the use of low RH (< 80%) for maritime transport and long-term storage of almond kernels. Practical Application High levels of relative humidity during storage/transport of almond kernels favor fungal growth, mycotoxin production, and secondary oxidation (rancidity). It is recommended to keep the almond kernels under low RH (< 80%) in maritime transport and long storage, especially in tropical countries.
- Technological processes for reduction of fungal and mycotoxin contamination of nutsPublication . Jelassi, Arij; Rodrigues, Paula; Pereira, Ermelinda; Kanoun, AlifaAlmond and hazelnut production in Portugal are 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 security. Mycotoxins are secondary metabolites produced by filamentous fungi that frequently contaminate these commodities. This work intended to evaluate the influence of storage conditions on the microbial and mycotoxin stability and safety of nuts throughout long-term storage. For that, almond and hazelnut samples were stored under different relative humidity (RH) conditions (60, 70 and 80%) at 25°C for up to 6 months. The storage of two almond varieties – Lauranne and Guara - under 60% and 70% RH at 25°C were further compared with storage at 4 ºC for 9 months. Microbial loads (aerobic mesophiles and yeasts and molds) were determined at post-harvest stage and after being submitted to preservation, and molds were identified morphologically and molecularly. Nuts were also subjected to multi- mycotoxin analysis by LC-MS/MS to determine their mycotoxin contamination level and profile. For hazelnuts, five fungal species were identified belonging to four fungal genera commonly associated with mycotoxin production: Alternaria, Aspergillus, Fusarium, and Penicillium. For hazelnuts, an important range of mycotoxin was detected after 6 months of storage with a remarkable cumulative amount in 80% RH at 25°C, when compared to 60% and 70% RH at 25°C. For almonds, 26 species were identified belonging to seven genera: Alternaria, Aspergillus, Cladosporium, Fusarium, Penicillium, Paecilomyces, Talaromyces. For the variety Guara, mycotoxins related to Aspergillus sect. Flavi such as Aflatoxin B1, B2, G1, G2, Averufin, Versicolorin C, Norsolorinic acid were detected only after nine months of storage at 70 and 60% RH at 25°C. Penicillium sp. mycotoxins as Quinolactacin A, Roquefortine C and Flavoglaucin were also detected. Flavoglaucin was present in all time-points and conditions of storage in important amounts. For the variety Lauranne, Penicillium sp. mycotoxins were detected such as Citrinin, Quinolactacins A and B, Roquefortines Cand D, Cyclopenin, Cyclopenol, Penitrem A, Viridicatin and Viridicatol. Mycotoxins related to Aspergillus sp. such as Aspulvinone E, Flavoglaucin, Paspalin, Asperglaucide, Asperphenamate, cyclo(L-Pro-L-Tyr) and cyclo(L-Pro-L-Val) were also detected.