Thermal transitions of gelatin evaluated using DSC sample pans of various seal integrities
Differential scanning calorimetry (DSC) has become a popular tool to investigate thermal transitions in food ingredients such as gelatin. Upon heating commercial gelatin samples beyond glass transition (T g) and melting (T m) temperatures, a relatively large endothermic transition (T i) can be observed. We have observed that both the peak temperature and the enthalpy of the T i transition are influenced by the integrity of the seal of the DSC pans used for the analysis. This study shows that escape of moisture from the DSC pan appears to be responsible for this effect. The effect of different types of DSC pans, as well as technique of sealing them on the T i transition were evaluated using DSC, SDT, and TG–MS.
KeywordsGelatin Temperature of isomerization DSC pan Seal integrity TG–mass spectrometry (TG–MS) Simultaneous DSC–TG (SDT)
The authors are grateful to TA Instruments, New Castle, DE for generating the simultaneous DSC–TG data on calfskin gelatin using their Q600SDT instrument, as well as Kraft Foods Global Inc. for their support.
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