title: Multivariate class modeling techniques applied to multielement analysis for the verification of the geographical origin of chili pepper.
abstract: Four class-modeling techniques (soft independent modeling of class analogy (SIMCA), unequal dispersed classes (UNEQ), potential functions (PF), and multivariate range modeling (MRM)) were applied to multielement distribution to build chemometric models able to authenticate chili pepper samples grown in Calabria respect to those grown outside of Calabria. The multivariate techniques were applied by considering both all the variables (32 elements, Al, As, Ba, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Fe, Ga, La, Li, Mg, Mn, Na, Nd, Ni, Pb, Pr, Rb, Sc, Se, Sr, Tl, Tm, V, Y, Yb, Zn) and variables selected by means of stepwise linear discriminant analysis (S-LDA). In the first case, satisfactory and comparable results in terms of CV efficiency are obtained with the use of SIMCA and MRM (82.3 and 83.2% respectively), whereas MRM performs better than SIMCA in terms of forced model efficiency (96.5%). The selection of variables by S-LDA permitted to build models characterized, in general, by a higher efficiency. MRM provided again the best results for CV efficiency (87.7% with an effective balance of sensitivity and specificity) as well as forced model efficiency (96.5%).
authors.affiliation: Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Via Pietro Bucci, Cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy.
authors.forename: Attilio
authors.initials: A
authors.lastname: Naccarato
authors.affiliation: Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Via Pietro Bucci, Cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy.
authors.forename: Emilia
authors.initials: E
authors.lastname: Furia
authors.affiliation: Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Via Pietro Bucci, Cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Sindona
authors.affiliation: Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Via Pietro Bucci, Cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy. Electronic address: a.tagarelli@unical.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Tagarelli
mesh_terms: D002212:Capsicum / Q000737:chemistry* / Q000145:classification*; D016002:Discriminant Analysis; D005843:Geography; D007558:Italy; D057230:Limit of Detection; D008962:Models, Theoretical; D015999:Multivariate Analysis; D025341:Principal Component Analysis
keywords: Authenticity; Chili pepper; Class modeling; ICP-MS; Multielement fingerprint; Statistical analysis