Mid infrared spectroscopy coupled with chemometric tools for qualitative analysis of canned tuna with sunflower medium

Feasibility study of discriminating the manufacturing process and sampling zone in ripened soft cheeses using attenuated total reflectance MIR and fiber optic diffuse reflectance VIS–NIR spectroscopy

Mid infrared spectroscopy and multivariate analysis: A tool to discriminate between organic and non-organic wines grown in Australia

Towards personalised saliva spectral fingerprints: Comparison of mid infrared spectra of dried and whole saliva samples

ABSTRACTThe presence of mercury in tuna is ubiquitous, so national authorities should guarantee food safety of canned tuna available on the market, according to legal regulations. The objective of this survey was to assess total mercury (T-Hg) levels in brands of canned tuna marketed in Cartagena, Colombia, and determine fish consumption-based risks after ingestion. For that purpose, 252 cans of tuna were collected, representing 6 brands (A–F), in 2 mediums (water and oil). Mean T-Hg levels were 0.66 ± 0.05 and 0.61 ± 0.05 µg g−1 wet weight, for water and oil, respectively. High T-Hg concentrations were measured in brands B and D. Only brands E and F guaranteed low risk for Hg-related health problems. According to Colombia’s legislation, 15.5% of the samples exceeded the maximum level of 1.0 µg g−1 for mercury and 18.3% was higher than limits as recommended by Food and Agriculture Organization/World Health Organisation (0.5 µg g−1). It was concluded that consumption of canned tuna could represent a high risk for the Colombian population, particularly to vulnerable groups.

Predicting the decomposability of arctic tundra soil organic matter with mid infrared spectroscopy

The mid-infrared spectroscopy: A novel non-invasive diagnostic tool for NASH diagnosis in severe obesity

Mercury content in the white and dark muscle of Skipjack tuna (Katsuwonus pelamis) along the canning process: Implications to the consumers

Utilisation of mid-infrared spectroscopy for determination of the geographic origin of Gruyère PDO and L’Etivaz PDO Swiss cheeses

The quality of strawberry powder depends on the freshness of the fruit that produces the powder. Therefore, identifying whether the strawberry powder is made from freshly available, short-term stored, or long-term stored strawberries is important to provide consumers with quality-assured strawberry powder. Nevertheless, such identification is difficult by naked eyes, as the powder colours are very close. In this work, based on the measurement of near-infrared (NIR) spectroscopy and mid-infrared (MIR) spectra of strawberry powered, good classification results of 100.00% correct rates to distinguish whether the strawberry powder was made from freshly available or stored fruit was obtained. Furthermore, partial least squares regression and least squares support vector machines (LS-SVM) models were established based on NIR, MIR, and combination of NIR and MIR data with full variables or optimal variables of strawberry powder to predict the storage days of strawberries that produced the powder. Optimal variables were selected by successive projections algorithm (SPA), uninformation variable elimination, and competitive adaptive reweighted sampling, respectively. The best model was determined as the SPA-LS-SVM model based on MIR spectra, which had the residual prediction deviation (RPD) value of 11.198 and the absolute difference between root-mean-square error of calibration and prediction (AB_RMSE) value of 0.505. The results of this work confirmed the feasibility of using NIR and MIR spectroscopic techniques for rapid identification of strawberry powder made from freshly available and stored strawberry.

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.

Near infrared spectroscopic imaging assessment of cartilage composition: Validation with mid infrared imaging spectroscopy

Mid-infrared (MIR) and near-infrared (NIR) spectra of crystalline menadione (vitamin K3) were measured and analyzed with aid of quantum chemical calculations. The calculations were carried out using the harmonic approach for the periodic model of crystal lattice and the anharmonic DVPT2 calculations applied for the single molecule model. The theoretical spectra accurately reconstructed the experimental ones permitting for reliable assignment of the MIR and NIR bands. For the first time, a detailed analysis of the NIR spectrum of a molecular system based on a naphthoquinone moiety was performed to elucidate the relationship between the chemical structure of menadione and the origin of the overtones and combination bands. In addition, the importance of these bands during interpretation of the MIR spectrum was demonstrated. The overtones and combination bands contribute to 46.4% of the total intensity of menadione in the range of 3600–2600 cm−1. Evidently, these bands play a key role in shaping of the C-H stretching region of MIR spectrum. We have shown also that the spectral regions without fundamentals may provide valuable structural information. For example, the theoretical calculations reliably reconstructed numerous overtones and combination bands in the 4000–3600 and 2800–1800 cm−1 ranges. These results, provide a comprehensive origin of the fundamentals, overtones and combination bands in the NIR and MIR spectra of menadione, and the relationship of these spectral features with the molecular structure.

Honey is considered as a premium food produced by honeybees. It is highly appreciated by consumers around the world and raises a major concern nowadays which is ensuring its authenticity in respect to its production and its botanical origin. In Lebanon, honey is mainly multifloral which makes its authentication rather difficult. While mid-infrared (MIR) spectroscopy combined with multivariate analysis has proven to be successful in authenticating unifloral honey, the challenge with Lebanese honey lies in assessing its performance with multifloral honey. Therefore, this work aims to test the performance of common components analysis (CCA) applied on mid-infrared spectra in the authentication of multifloral Lebanese honey. For this purpose, 96 multifloral Lebanese honey samples of different floral sources were collected from different regions of the Lebanese territory and analyzed using MIR spectroscopy. CCA applied to the spectral data, allowed a separation between honeydew honey samples and floral honey samples. In addition, honey samples collected from the Bekaa plain region were differentiated from the other honey samples collected from all the other Lebanese geographical regions. This discrimination between the groups of honey samples is based essentially on their sugar composition.

Sterlet is a perishable product; therefore, its freshness monitoring and shelf-life evaluation are important. In this study, a series of analytical techniques named physicochemical, microbiological, sensory, colorimetric, and mid-infrared and fluorescence spectroscopies were applied on Sterlet (Acipenser ruthenus) samples during 18 days of storage at 4 °C. The water content increased from 72.8 g/100 g on day 1 to 77.81 g/100 on day 14. Regarding the peroxide value (PV), the initial value was 4.17 meq/kg of Sterlet on day 1, reaching a maximum on day 4 (4.9 meq/kg of Sterlet), and then it decreased gradually, attaining a value of 0.7 meq/kg of Sterlet on day 18. Generally, the thiobarbituric acid reactive substance (TBARS), total viable count (TVC) and psychrotrophic count (PTC) increased during the storage time and increased from 0.03 to 0.13 MDA eq./kg of Sterlet sample, 2.27 to 9.09 log10 CFU/g, and 2.18 to 9.15 log10 CFU/g, respectively, on day 1 and 18, respectively. The microbiological and sensory analyses indicated that Sterlet samples were acceptable for human consumption up to 7 days of storage at 4 °C. This result was confirmed by fluorescence measurements, since the principal component analysis (PCA) applied to the NADH and MIR spectra allowed for a clear differentiation between Sterlet samples aged 7 days or less from the others. This trend was confirmed by the factorial discriminant analysis (FDA) applied to the NADH and MIR spectra, since a correct classification with leave-one cross-validation of 94.44% was observed. In addition, the heatmap of the Pearson correlation coefficients showed high correlations between overall acceptability and microbiology parameters and the structural properties of Sterlet samples during storage, indicating that the modifications observed at the macroscopic level were related to those notedat the molecular scale.

This work aimed at employing partial least square discriminant analysis (PLS2-DA), allied to mid-infrared (MIR) spectroscopy as an analytical method for simultaneous classification of biodiesels from different oils (soybean and used frying oil) and routes (methylic and ethylic).The evaluation of the model was verified through values of sensitivity and specificity for each parameter, in the interest class.PLS2-DA model showed 100% correct classification in the discrimination of types of biodiesels.Therefore, the proposed methodology is fast, because it allows simultaneous classification of different types of biodiesels.Consequently, it can be used in quality control of this type of biofuel.