Effect of heat processing methods on spectral images of biological tissues (yellow canola seed protein) using advanced synchrotron-based infrared technique

The objective of this study was to use the synchrotron-based SR-IMS imaging technique to study heating effect on protein molecular imaging of yellow canola seed tissues. The heating methods included the control (raw), autoclaving at 120°C for 1 h and dry roasting at 120°C for 1 h. The spectral images were carried out from outside to inside of the yellow seed tissues under functional groups of amide I at ca. 1650 cm⁻¹ and amide II at ca. 1550 cm⁻¹. The results showed protein amide I and II spectral features were affected by heating methods. The heat processing induced changes in protein secondary structure profile. Different processing had different impact on protein secondary structure profile. The spectral images of the yellow seed tissues were different among the control, autoclaved and dry heated treatments. Future study is needed to confirm such changes with a large number of seed samples and compare the response to different heat-related processing between yellow canola seed (with thin seed coat) and dark-brown canola seed (with thick seed coat).