Abstract
Various amounts of tryptophan were attached to three food protein products: soy protein isolates, spray-dried egg white and gluten, using a water-soluble carbodiimide method. The extent of amidation was determined by a spectrophotometric method. Raman spectra (600–2000 cm −1) of the modified proteins were obtained and analyzed. The phenyl stretching vibration at 1552 cm −1, directly attributed to the attached tryptophan, was used as a marker band, and increases in band intensity were observed in the modified protein samples. Calibration curves were constructed by plotting the intensity ratio of the 1552 cm −1 band to the 1003 cm −1 phenylalanine stretching band (used as an internal standard) against the amount of tryptophan attached. High correlation coefficients, ( r) ⩾ 0.99, were obtained from these calibration curves. The Raman spectral data showed a transition from ordered conformation to random coil structures in the amidated food protein products.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.