All 26 freeze-dried microalgae strains were analysed by the traditional analysis techniques for protein, carbohydrate and lipid contents as outlined above, the results are presented in Table 1. All values are presented on a dry ash free basis. Although the newly proposed Py–GC–MS method does not measure the inorganic fraction of the microalgae samples, the amount of material pyrolysed is related to the organic fraction of the algae. A high inorganic fraction in algae, results in a lower pyrolysis signal from a smaller percentage of algae being pyrolysed compared to a low ash sample. Due to the MS response being normalised to the amount of algae pyrolysed the results are related to the organic fraction of the algae which is why we are comparing the results from the new method to the dry ash free biochemical composition.