Water status evolution of pork blocks at different cooking procedures: A two-dimensional LF-NMR T1-T2 relaxation study

A two-dimensional low-field nuclear magnetic resonance (LF-NMR) T-1-T-2 relaxation technique was developed to contrast the water status evolution during different cooking procedures (steam and boiling cooking). Meat quality, water distribution, microstructure and protein properties were determined. The results showed that steamed meats had lower cooking loss and shear force, but higher redness, proton relaxation intensity (T-1 and T-2) and proton density than boiled meats. The differences in water distribution between the two cooking procedures appeared at approximately 40 degrees C, with acceleration at 60 degrees C, and the most remarkable difference was shown at 80 degrees C. Boiling resulted in more damage to muscle structure and greater protein denaturation than steam cooking. Meanwhile, alpha-helixes and beta-turns increased, but beta-sheets and random coils decreased in steamed meats compared with boiled meats. Changes in microstructural and protein properties were closely associated with water status evolution in cooked meat during cooking.

Automated summary

The research found that steamed meats had lower cooking loss and shear force, but higher redness, proton relaxation intensity, and proton density compared to boiled meats; differences in water distribution between the two cooking procedures appeared at around 40 degrees Celsius, with the most significant difference at 80 degrees Celsius; steaming resulted in more muscle structure damage and protein denaturation compared to boiling.