NEW INSIGHT INTO THE DYNAMICS OF WATER AND MACROMOLECULES IN MEAT DURING DRIP AS PROBED BY PROTON CPMG NMR

BACKGROUND: Three distinct proton spin-spin relaxation rate components in meat are known to be associated with three corresponding spatial domains possessing different molecular ratios of water and/or macromolecules (extra- and inter/intramyofibrillar). In this work we acquire the proton signal intensity and corresponding relaxation rate of the three components during a drip experiment with the objective to probe the irreversible migration of water and macromolecules between domains with drip time. RESULTS: Each CPMG relaxation curve is decomposed into three relevant and distinct relaxation components (intensity and relaxation rate). A first-order kinetic model is adopted which enables the irreversible and slow “migration” of water and macromolecules between domains to be monitored. A detailing of the kinetic model applied is thoroughly discussed. CONCLUSIONS: The amount of water and macromolecules within the respective domains in meat is monitored and quantified by in situ CPMG measurements during drip. The observed and irreversible change in proton intensity/relaxation rate during drip is rationalized by a slow migration of water molecules and macromolecules between the domains. GENERAL SIGNIFICANCE: To shed new light on the water holding capacity in biological material by probing the slow migration properties of water/macromolecules between different domains during drip loss.