Water properties during cooking of pork studied by low-field NMR relaxation: effects of curing and the RN(-)-gene.

Using low-field NMR transverse relaxation measurements, the physico-chemical state of water in meat was followed continuously during cooking of 20 uncured and 20 cured pork samples from RN-carriers (n=20) and non-carriers (n=20). The obtained relaxation data were analysed using (i) distributed exponential fitting, and (ii) principal component analysis (PCA). Distributed exponential fitting revealed transition from a system with relatively well-separated components to a less well-defined system with a wide distribution of relaxation times and merged components during cooking.

The significance of cooling rate on water dynamics in porcine muscle from heterozygote carriers and non-carriers of the halothane gene-a low-field NMR relaxation study.

The post mortem changes in the chemical/physical state distribution of water were followed in pig muscle (M. longissimus dorsi) from heterozygote (n=12) and non-carriers (n=12) of the halothane gene exposed to two different cooling profiles using continuous low-field NMR relaxation measurements. T(2) relaxation data were analyzed using distributed exponential fitting analysis.

Prediction of technological quality (cooking loss and Napole Yield) of pork based on fresh meat characteristics.

In order to investigate if cooking loss and Napole Yield can be predicted from various fresh meat characteristics, pH (1, 15, 30, 60, 120 min and 24 h post mortem), temperature (1, 15, 30, 60, 120 min and 24 h post mortem), water-holding capacity (Honikel's drip loss method and centrifugation loss), and NMR T2 relaxation 24 h post mortem were measured in fresh porcine M. longissimus dorsi from 102 Hampshire crossbreeds of known RN(-) genotype. Subsequently, cooking loss and Napole Yield were determined on cooked and cured, cooked samples, respectively, and partial least squares regression (PLS) was carried out to investigate possible intercorrelations between the physico-chemical measurements performed on the fresh meat and cooking loss/Napole Yield.

Post-mortem changes in porcine M. longissimus studied by solid-state 13C cross-polarization magic-angle spinning nuclear magnetic resonance spectroscopy.

Solid-state (13)C cross-polarization (CP) magic-angle spinning (MAS) nuclear magnetic resonance (NMR) experiments are carried out for the first time on rapidly frozen muscle biopsies taken in M. longissimus in vivo and at 1 min, 45 min, and 24 h post-mortem from three pigs. Two of the pigs were CO(2)-stunned (control animals), and one was pre-slaughter-stressed (treadmill exercise) followed by electrical stunning to induce difference in metabolism post-mortem.

Changes in orcine muscle water characteristics during growth--an in vitro low-field NMR relaxation study.

This study investigates the effects of developmental stage and muscle type on the mobility and distribution of water within skeletal muscles, using low-field (1)H-NMR transverse relaxation measurements in vitro on four different porcine muscles (M. longissimus dorsi, M. semitendinosus, M.

Post mortem energy metabolism and meat quality of porcine M. longissimus dorsi as influenced by stunning method - A (31)P NMR spectroscopic study.

Post mortem changes in phosphorus metabolites and pH were studied in M. longissimus dorsi from pigs (n=10) stunned either by CO(2) (n=3), electrical (n=2), captive bolt pistol (n=2) or by anesthesia (ketamine) (n=3). (31)P-NMR spectroscopy revealed significant effects of stunning method on changes of the various phosphorus metabolites in the muscle post mortem, with the effect being most pronounced on the degradation of phosphocreatine (PCr).

Continuous distribution analysis of T(2) relaxation in meat-an approach in the determination of water-holding capacity.

Continuous distribution analysis as well as traditional bi-exponential fitting analysis were carried out on NMR T(2) relaxation data measured 24 h post-mortem in 74 pork meat samples from M. longissimus dorsi. Areas of relaxation populations found by continuous distribution analysis and corresponding time constants were determined.