title: Analysis of spreadable cheese by Raman spectroscopy and chemometric tools.
abstract: In this work, FT-Raman spectroscopy was explored to evaluate spreadable cheese samples. A partial least squares discriminant analysis was employed to identify the spreadable cheese samples containing starch. To build the models, two types of samples were used: commercial samples and samples manufactured in local industries. The method of supervised classification PLS-DA was employed to classify the samples as adulterated or without starch. Multivariate regression was performed using the partial least squares method to quantify the starch in the spreadable cheese. The limit of detection obtained for the model was 0.34% (w/w) and the limit of quantification was 1.14% (w/w). The reliability of the models was evaluated by determining the confidence interval, which was calculated using the bootstrap re-sampling technique. The results show that the classification models can be used to complement classical analysis and as screening methods.
authors.affiliation: Núcleo de Espectroscopia e Estrutura Molecular (NEEM), Departamento de Química, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, MG, Brazil.
authors.forename: Kamila de Sá
authors.initials: Kde S
authors.lastname: Oliveira
authors.affiliation: Núcleo de Espectroscopia e Estrutura Molecular (NEEM), Departamento de Química, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, MG, Brazil.
authors.forename: Layce de Souza
authors.initials: Lde S
authors.lastname: Callegaro
authors.affiliation: Tate & Lyle Gemacom Tech, 36092-050 Juiz de Fora, MG, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Stephani
authors.affiliation: Núcleo de Espectroscopia e Estrutura Molecular (NEEM), Departamento de Química, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, MG, Brazil.
authors.forename: Mariana Ramos
authors.initials: MR
authors.lastname: Almeida
authors.affiliation: Núcleo de Espectroscopia e Estrutura Molecular (NEEM), Departamento de Química, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, MG, Brazil. Electronic address: luiz.oliveira@ufjf.edu.br.
authors.forename: Luiz Fernando Cappa
authors.initials: LF
authors.lastname: de Oliveira
mesh_terms: D000465:Algorithms; D002138:Calibration; D002611:Cheese / Q000032:analysis*; D016002:Discriminant Analysis; D005504:Food Analysis / Q000379:methods*; D016018:Least-Squares Analysis; D008055:Lipids / Q000737:chemistry; D015999:Multivariate Analysis; D011786:Quality Control; D015203:Reproducibility of Results; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013213:Starch / Q000032:analysis*
chemical_list: D008055:Lipids; D013213:Starch
keywords: PLS-DA; Quality control; Raman spectroscopy; Spreadable cheese; Starch