Academic article

Analyzing pH-induced changes in a myofibril model system with vibrational and fluorescence spectroscopy

Andersen, Petter Vejle; Veiseth-Kent, Eva; Wold, Jens Petter

Publication details

Journal: Meat Science, vol. 125, p. 1–9, 2017

Publisher: Elsevier

International Standard Numbers:
Printed: 0309-1740
Electronic: 1873-4138

Open Access: none

Links:
DOI

The decline of pH and ultimate pH in meat postmortem greatly influences meat quality (e.g. water holding capacity). Four spectroscopic techniques, Raman, Fourier transform infrared (FT-IR), near infrared (NIR) and fluorescence spectroscopy, were used to study protein and amino acid modifications to determine pH-related changes in pork myofibril extracts at three different pH-levels, 5.3, 5.8 and 6.3. Protonation of side-chain carboxylic acids of aspartic and glutamic acid and changes in secondary structure, mainly the amide I–III peaks, were the most important features identified by Raman and FT-IR spectroscopy linked to changes in pH. Fluorescence spectroscopy identified tryptophan interaction with the molecular environment as the most important contributor to changes in the spectra. NIR spectroscopy gave no significant contributions to interpreting protein structure related to pH. Results from our study are useful for interpreting spectroscopic data from meat where pH is an important variable.