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Molecular structure modifications of camel milk (CaM) and cow milk (CM) mixtures during coagulation were investigated combining mid‐infrared (MIR) spectroscopic monitoring with Parallel Factor Analysis (PARAFAC) and particle‐size measurements. To evaluate the structure evolution at the molecular level, five different milk formulations were prepared using the following volume fractions of CaM in the mixtures: 100, 75, 50, 25, and 0. Regarding MIR spectroscopy, wavelength ranges located between 3,000 and 2,800 cm−1 corresponding to fatty acids; from 1,700 to 1,500 cm−1, related to amide I and II bands; and in the 1,500–900 cm−1 range called the fingerprint region were considered for the characterization of milk coagulation kinetics. MIR spectroscopy with PARAFAC was allowed for the identification of modifications at the molecular level depending on the coagulation time and milk composition. This was also confirmed by canonical correlation analysis, which demonstrated a high degree of correlation between the casein particle‐size distributions and MIR spectra measured during coagulation. Novelty impact statement: PARAFAC coupled with MIR spectroscopy were successfully used to monitor coagulation of CM, CaM, and their mixtures (CaM, CM, 1CaM:1CM, 1CaM:3CM, 3CaM:CM1; v/v). PARAFAC coupled with MIR spectroscopy were successfully used to differentiate between physicochemical phenomenon occurring during coagulation of different mixtures of CM, CaM and their mixtures. Canonical correlation analysis (CCA) of MIR spectra and particle‐size distribution during milk coagulation demonstrated a strong relationship between the formation of casein aggregates and the variation of the MIR spectral data. [ABSTRACT FROM AUTHOR]

The purpose of this work was to assess the potential of 2T2D COS PLS-DA (two-trace two-dimensional correlation spectroscopy and partial least squares discriminant analysis) in conjunction with Visible Near infrared multispectral imaging (MSI) as a quick, non-destructive, and precise technique for classifying three beef muscles - Longissimus thoracis, Semimembranosus, and Biceps femoris - obtained from three breeds - the Blonde d'Aquitaine, Limousine, and Aberdeen Angus. The experiment was performed on 240 muscle samples. Before performing PLS-DA, spectra were extracted from MSI images and processed by SNV (Standard Normal Variate), MSC (Multivariate Scattering Correction) or AREA (area under curve equal 1) and converted in synchronous and asynchronous 2T2D COS maps. The results of the study highlighted that combining synchronous and asynchronous 2T2D COS maps before performing PLS-DA was the best strategy to discriminate between the three muscles (100% of classification accuracy and 0% of error). • Authentication and traceability of beef muscles are tremendously important. • Vis-Nir Multispectral imaging was used to discriminate 3 beef muscles. • Highest muscles discrimination was obtained after applying 2T2D COS to MSI spectra. • Concatenation of synchronous and asynchronous maps allowed to reach 0% error. [ABSTRACT FROM AUTHOR]