Furan formation as a function of pressure, temperature and time conditions in spinach purée

- Furan concentration increased as a function of processing temperature and time.
- Rate of furan formation was (apparently) independent of precursor concentration.
- Pressure level of 600 MPa had no effect on the rate of furan formation.
- Furan reduction by high-pressure high-temperature processing due to shorter process.

In recent studies, innovative high-pressure high-temperature processing (HPHT) has presented itself as an interesting alternative for furan reduction in sterilized, vegetable-based foods. In order to explain the observed furan reduction following HPHT treatment, furan formation was studied under a range of pressure, temperature and time conditions, using spinach purée as a case study. For all the treatments, no furan was detected during the dynamic heating-up phase, followed by a steady increase in furan concentrations at isothermal(-isobaric) conditions. The increase in furan concentrations at isothermal(-isobaric) treatment conditions could be adequately described by an empirical, zero-order model. A pressure level of 600 MPa did not affect the rate of furan formation in spinach purée, as opposed to the processing temperature and time. As a result, the reduced furan concentrations for HPHT processing could be explained by the faster heating and cooling rates, resulting in shorter processing times as compared with conventional retort processing.