## 3 Results  
The prepared olive paste samples were assessed to determine the contamination levels of aflat and ochratoxin A with the ELISA test. In parallel, the same analyses were carried out with the reference method LC-MS/MS. In this regard, the chromatographic analysis showed that all samples had mycotoxin levels below the LOQ (OTA A: 0.48 ug/kg), while false positives were obtained using the ELISA method. Specifically, for ochratoxin A, the results showed several false positives for both kits, especially in the first and fourth shipments, while all negatives were confirmed (Table 2). Statistical analysis was applied to cultivars, methods, and kits. Regarding the cultivars, the data obtained with the ELISA showed that contamination of the Nocellara Etnea cultivar (3.47 ug/kg) was significantly different from the contamination of the other cultivars. On the other hand, statistical analysis applied to methods displayed that the natural method (3.30 ug/kg) was statistically different from the others, while the Californian pitted method differed from both the natural method and the others (3.10 ug/kg). Finally, among the kits used (Veratov(r) vs. AgraQuant(r)), significant differences were also identified (Table 3). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Mass [\(m\)]** & **Formula [M]** & **Species** & **Polarity** & **N (CE)** & **Fragments** \\ \hline Aflatoxin B1 & 313.07066 & C\({}_{17}\)H\({}_{12}\)O\({}_{6}\) & +H & Positive & 50 & 285.07578 \\  & & & & & 270.05227 \\ \hline Aflatoxin B2 & 315.08631 & C\({}_{17}\)H\({}_{14}\)O\({}_{6}\) & +H & Positive & 40 & 287.0914 \\  & & & & & 259.76015 \\ \hline Aflatoxin G1 & 329.06558 & C\({}_{17}\)H\({}_{12}\)O\({}_{7}\) & +H & Positive & 50 & 243.06527 \\  & & & & & 283.06014 \\ \hline Aflatoxin G2 & 331.08123 & C\({}_{17}\)H\({}_{14}\)O\({}_{7}\) & +H & Positive & 50 & 313.07044 \\  & & & & & 285.0757 \\ \hline Aflatoxin B1-13C17 & 330.12770 & \({}^{[13]}\)C\({}_{17}\)H\({}_{12}\)O\({}_{6}\) & +H & Positive & 50 & 301.12866 \\  & & & & & 285.10166 \\ \hline Aflatoxin B2-13C17 & 332.14335 & \({}^{[13]}\)C\({}_{17}\)H\({}_{14}\)O\({}_{6}\) & +H & Positive & 50 & 303.14429 \\  & & & & & 273.10633 \\ \hline Aflatoxin G1-13C17 & 346.12261 & \({}^{[13]}\)C\({}_{17}\)H\({}_{12}\)O\({}_{7}\) & +H & Positive & 50 & 257.11147 \\  & & & & & 299.11293 \\ \hline Aflatoxin G2-13C17 & 348.13826 & \({}^{[13]}\)C\({}_{17}\)H\({}_{14}\)O\({}_{7}\) & +H & Positive & 50 & 330.12726 \\  & & & & & 301.12883 \\ \hline Ochratoxin A & 404.08954 & C\({}_{20}\)H\({}_{18}\)CINO\({}_{6}\) & +H & Positive & 30 & 257.02083 \\  & & & & & 239.01029 \\ \hline Ochratoxin A-13C20 & 424.15664 & \({}^{[13]}\)C\({}_{20}\)H\({}_{18}\)CINO\({}_{6}\) & +H & Positive & 30 & 250.04697 \\  & & & & & 268.05869 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of standards and internal standards. Concerning aflatoxin content, the results of the LC-MS/MS showed that the samples analyzed were below the LOQ (Afla B1 and G1: 1.26 ug/kg; Afla B2 and G2: 0.32 ug/kg), while the ELISA test gave some false positives, but significantly fewer than those found for ochratoxin A (Table 4). False positives emerged mainly with the AgraQuant(r) kit, at around 25%, while for the Veratov(r) kit, they were below 3%. Table 4 presents the average contents of aflat in the batch processing of the olive paste samples belonging to the four shipping groups (ug/kg), \(\pm\)SD (standard deviation), n = 4. Statistical analysis on cultivars, methods, and kits applied to this type of mycotoxin showed significant differences. For cultivars, the differences were identified between the groups of Itrana Bianca (3.77 ug/kg) and Hoijblanca Nera (3.61 ug/kg), with an intermediate group of Conservolea Nera (3.09 ug/kg), Nocellara del Belice (3.02 ug/kg), and Bella di Cerignola (3.01 ug/kg), and a significantly lower value for Nocellara Etnea (2.77 ug/kg). On the other hand, among the transformation methods, only the Californian