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In this preliminary work fresh and frozen-thawed chicken breast samples were investigated by means of Diffusion Tensor Micro Imaging (µDTI) with the aim of looking for changes in the anisotropic diffusion properties of water upon freezing and storage at low temperature. Four groups of samples were evaluated (G1-G4), namely fresh samples (G1), samples frozen in liquid N2 and stored at -30 °C for 1 day (G2), samples frozen in liquid N2 and stored at -30 °C for 11 days (G3) and samples frozen at -30°C and stored for 11 days (G4). Non parametric LDA of the most important rotationally invariant parameters obtained from the µDTI data reveals a significant difference (P < 0.001) between fresh and frozen samples. Analysis of the LDA biplot of our data (below) suggests that, contrary to what could be expected, water anisotropy increases upon freezing, probably because of a lateral shrinkage of the meat fibers produced by ice crystals growth in the extracellular spaces. http://www.biopolymersolutions.co.uk/nmr/PDF/posters/Venturi.pdf

In the last few years, the poultry industry has seen a significant decrease in the meat quality properties during the summer season. The objective of this study was to evaluate the seasonal effect (summer and winter) on turkey meat quality assessed both by conventional and Low-Resolution Nuclear Magnetic Resonance (LR-NMR) analysis. Eighty-eight breast muscles (35 winter and 53 summer) from BUT-Big 6 turkeys belonging to 16 flocks, were randomly collected from a commercial processing plant. The samples were analysed for transverse relaxation times (T2) by LR-NMR and for initial pH (15min post mortem), ultimate pH (24h post mortem) and pH after cooking, temperature at 15 min post mortem, water holding capacity (WHC) (drip loss, filter paper wetness and cooking loss), colour of raw (24h post mortem) and cooked meat and chemical composition (moisture, lipids and proteins). The results indicate that during the summer season turkey breast meat undergoes a relevant WHC decrease. Cluster analysis of the raw LR-NMR data evidenced the presence of two groups corresponding to samples harvested in each different season. Correlations between the LR-NMR signal and the conventional parameters measuring WHC were obtained by a recently proposed type of principal component regression (PCR) termed relative standard deviation PCR.

Many different ways have been devised over the years for analyzing phospholipids in soln. by 31P NMR. One promising method entails the use of the so-called CUBO solvent, a ternary mixt. of DMF, triethylamine and guanidinium hydrochloride. As this interesting system seems to have been overlooked in the literature, we present here a study on the quantification of phospholipids and lysophospholipids contained in 10 samples of com. lecithin using the CUBO/31P NMR method. Cluster anal. and principal component anal. of the NMR data showed clear differences among the samples according to the actual lecithin producer. Multivariate anal. of the chem. and phys. parameters of the samples confirmed these differences.

The measure of the proton nucleus transverse relaxation rate (R2) is a good candidate for evaluating the quality of intact eggs albumen. For its succesful use some physical characteristics it depends on have been evaluated.