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Abstract: In this investigation, the effect of NaCl, KCl and MgSO4 on bovine meat was studied, where the salts were used in standard marinades in 5.5% concentration. The effect of salts on secondary structure of the myofibrillar proteins, protein–water interactions, WHC, and sensory properties of the meat was followed by carrying out FTIR and NIR measurements, cooking loss and sensory analysis. The information obtained by spectroscopic analysis was integrated by using CPCA. This revealed that MgSO4 increased ratio of α-helices and C O and NH groups (followed by FTIR) that are involved in H-bonding with surrounding water molecules (followed by NIR). This was also supported by increased WHC. Conversely, KCl reduced WHC of meat and was correlated to non-hydrogenated C O and NH groups. Furthermore, the sensory analysis confirmed that MgSO4 was acceptable only when the share of this salt in the mixture was one third. [Copyright &y& Elsevier]

Abstract: In this paper a combination of NIR spectroscopy and FTIR and Raman microspectroscopy was used to elucidate the effects of different salts (NaCl, KCl and MgSO4) on structural proteins and their hydration in muscle tissue. Multivariate multi-block technique Consensus Principal Component Analysis enabled integration of different vibrational spectroscopic techniques: macroscopic information obtained by NIR spectroscopy is directly related to microscopic information obtained by FTIR and Raman microspectroscopy. Changes in protein secondary structure observed at different concentrations of salts were linked to changes in protein hydration affinity. The evidence for this was given by connecting the underlying FTIR bands of the amide I region (1700–1600cm−1) and the water region (3500–3000cm−1) with water vibrations obtained by NIR spectroscopy. In addition, Raman microspectroscopy demonstrated that different cations affected structures of aromatic amino acid residues differently, which indicates that cation–π interactions play an important role in determination of the final structure of protein molecules. [Copyright &y& Elsevier]

In this paper we present a method for transferring calibrations between different spectrometers based on assigning wavelength correspondence. It has been tested for near-infrared (NIR) and Raman spectroscopic instruments, and three examples are included in the paper. The calibration transfer is done in three steps: first wavelength correspondence is established. Second, PLS models are built and tuned for the new spectrometer. Third, the PLS models are slope and bias corrected. The advantages with this approach are that it does not require transfer samples and that there is only one parameter to tune: the number of PLS components. While a few samples with reference values are required for the tuning, it is fewer than methods with multiple parameters that need to be tuned. • Calibration transfer between different spectrometers using wavelength correspondence. • Calibration transfer without transfer samples. • Calibration transfer applied on NIR and Raman spectrometers. [ABSTRACT FROM AUTHOR]

Raman, near-infrared and fluorescence spectroscopy were evaluated for determination of collagen content in ground meat. Two sample sets were used (i.e. ground beef and ground poultry by-products), and collagen concentrations (measured as hydroxyproline) varied in the ranges 0.1–3.3% in the beef samples and 0.4–1.5% in the poultry samples. Similar validation results for hydroxyproline were obtained for NIRS (R2 = 0.82 and RMSECV = 0.11%) and Raman (R2 = 0.81 and RMSECV = 0.11%) for the poultry samples. For the beef samples, NIRS obtained slightly less accurate results (R2 = 0.89, RMSECV = 0.25%) compared to Raman (R2 = 0.94, RMSECV = 0.19%), most likely due to less representative sampling. Fluorescence spectroscopy gave higher prediction errors (RMSECV = 0.50% and 0.13% for beef and poultry, respectively). This shows that Raman spectroscopy employing a scanning approach for representative sampling is a potential tool for on-line determination of collagen in meat. • Non-destructive determination of collagen in meat products by Raman spectroscopy. • Regression models were compared for different spectroscopic techniques. • Specific models for collagen and proteins are possible with Raman spectroscopy. [ABSTRACT FROM AUTHOR]