title: Rapid prediction of ochratoxin A-producing strains of Penicillium on dry-cured meat by MOS-based electronic nose.
abstract: The availability of rapid diagnostic methods for monitoring ochratoxigenic species during the seasoning processes for dry-cured meats is crucial and constitutes a key stage in order to prevent the risk of ochratoxin A (OTA) contamination. A rapid, easy-to-perform and non-invasive method using an electronic nose (e-nose) based on metal oxide semiconductors (MOS) was developed to discriminate dry-cured meat samples in two classes based on the fungal contamination: class P (samples contaminated by OTA-producing Penicillium strains) and class NP (samples contaminated by OTA non-producing Penicillium strains). Two OTA-producing strains of Penicillium nordicum and two OTA non-producing strains of Penicillium nalgiovense and Penicillium salamii, were tested. The feasibility of this approach was initially evaluated by e-nose analysis of 480 samples of both Yeast extract sucrose (YES) and meat-based agar media inoculated with the tested Penicillium strains and incubated up to 14 days. The high recognition percentages (higher than 82%) obtained by Discriminant Function Analysis (DFA), either in calibration and cross-validation (leave-more-out approach), for both YES and meat-based samples demonstrated the validity of the used approach. The e-nose method was subsequently developed and validated for the analysis of dry-cured meat samples. A total of 240 e-nose analyses were carried out using inoculated sausages, seasoned by a laboratory-scale process and sampled at 5, 7, 10 and 14 days. DFA provided calibration models that permitted discrimination of dry-cured meat samples after only 5 days of seasoning with mean recognition percentages in calibration and cross-validation of 98 and 88%, respectively. A further validation of the developed e-nose method was performed using 60 dry-cured meat samples produced by an industrial-scale seasoning process showing a total recognition percentage of 73%. The pattern of volatile compounds of dry-cured meat samples was identified and characterized by a developed HS-SPME/GC-MS method. Seven volatile compounds (2-methyl-1-butanol, octane, 1R-α-pinene, d-limonene, undecane, tetradecanal, 9-(Z)-octadecenoic acid methyl ester) allowed discrimination between dry-cured meat samples of classes P and NP. These results demonstrate that MOS-based electronic nose can be a useful tool for a rapid screening in preventing OTA contamination in the cured meat supply chain.
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: vincenzo.lippolis@ispa.cnr.it.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Lippolis
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: massimo.ferrara@ispa.cnr.it.
authors.forename: Massimo
authors.initials: M
authors.lastname: Ferrara
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: salvatore.cervellieri@ispa.cnr.it.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Cervellieri
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: anna.damascelli@ispa.cnr.it.
authors.forename: Anna
authors.initials: A
authors.lastname: Damascelli
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: filomena.epifani@ispa.cnr.it.
authors.forename: Filomena
authors.initials: F
authors.lastname: Epifani
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: michelangelo.pascale@ispa.cnr.it.
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Pascale
authors.affiliation: Institute of Sciences of Food Production (ISPA), CNR-National Research Council of Italy, Via G. Amendola 122/O, 70126 Bari, Italy. Electronic address: giancarlo.perrone@ispa.cnr.it.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Perrone
mesh_terms: D020001:1-Butanol / Q000737:chemistry; D000081008:Bicyclic Monoterpenes; D053138:Cyclohexenes / Q000737:chemistry; D062609:Electronic Nose; D000077222:Limonene; D008461:Meat Products / Q000382:microbiology*; D039821:Monoterpenes / Q000737:chemistry; D009183:Mycotoxins / Q000096:biosynthesis*; D009793:Ochratoxins / Q000096:biosynthesis*; D010407:Penicillium / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D013729:Terpenes / Q000737:chemistry
chemical_list: D000081008:Bicyclic Monoterpenes; D053138:Cyclohexenes; D039821:Monoterpenes; D009183:Mycotoxins; D009793:Ochratoxins; D013729:Terpenes; C025589:ochratoxin A; D020001:1-Butanol; D000077222:Limonene; C005451:alpha-pinene
keywords: Dry-cured meat; Electronic nose; Metal oxide sensors; Penicillium nordicum; Rapid method