Comparative evaluation of an ISO 3632 method and an HPLC-DAD method for safranal quantity determination in saffron

- Comparison between UV-vis and HPLC-DAD method for safranal determination.
- Overestimation in the safranal determination by UV-vis.
- Interference of cis-crocetin esters and other compounds in the UV-vis measure.
- No relationship between ISO quality categories and safranal content by HPLC-DAD.

The aim of this work was a comparison of the ISO 3632 (2011) method and an HPLC-DAD method for safranal quantity determination in saffron. Samples from different origins were analysed by UV-vis according to ISO 3632 (2011) and by HPLC-DAD. Both methods were compared, and there was no correlation between the safranal content obtained by UV-vis and HPLC-DAD. An over-estimation in the UV-vis experiment was observed, which was related to the cis-crocetin esters content, as well as other compounds. The results demonstrated that there was no relationship between ISO quality categories and safranal content using HPLC-DAD. Therefore, HPLC-DAD might be preferable to UV-vis for determining the safranal content and the classification of saffron for commercial purposes. In addition, HPLC-DAD was adequate for determining the three foremost parameters that define the quality of saffron (crocetin esters, picrocrocin and safranal); therefore, this approach could be included in the ISO 3632 method (2011).