Comparing thermal and high pressure processing of carrots at different processing intensities by headspace fingerprinting

The comparison of thermal and high pressure (HP) processing of carrots was addressed by an untargeted approach, with the aim of taking into account unexpected effects, and possibly uncover unknown compounds resulting from HP processing. Headspace GC-MS fingerprinting proved to be a useful tool in comparing their impact and to investigate the effect of increasing processing intensity (mild pasteurisation, severe pasteurisation and sterilisation). Important impact differences between thermal and high pressure (HP) processing were revealed, which became more pronounced upon increasing processing intensity. The majority could be related to Maillard reactions (furans), unsaturated fatty acid oxidation (aliphatic aldehydes) and carotenoid degradation. These reactions occurred significantly more during thermal processing and were determined by the thermal load, applied during processing. Only a few volatiles were exposed with higher concentration after HP treatment at some processing intensity levels, which could be attributed to enzymatic activities and terpinolene oxidation.Industrial relevanceThe extensive nature of this investigation and the corresponding results can be considered of key importance for further implementation of HP technology in the food industry, since a correct and complete assessment of process-induced changes is of major importance in the context of legislative aspects of novel processing technologies.

► Untargeted approach to compare thermal and high pressure (HP) processing of carrots. ► Fair comparison by selecting equivalent processing conditions (microbial safety). ► Important impact differences, more pronounced upon increasing processing intensity. ► More Maillard reactions, lipid and carotenoid degradation during thermal processing. ► Only a few volatiles exposed with higher concentration after HP treatment.