QUAFETY Scientists have reached the last deliverable N. 2.12 of workpackage N. 2, which is aimed at providing useful tools for process control to the fresh-cut industry based on non-destructive and rapid measurements or evaluation, and at enhancing the final quality of the product. The work carried out within workpackage N. 2 has been led by University of Cardiff (UK).The aim of deliverable N. 2.12. was to use analysis of VOCs (Volatile Organic Compounds) to assess effects of 1) postharvest storage conditions, 2) processing, and 3) contamination of pathogens, and to identify suitable markers for assessing quality. Work was focused on melon and rocket salad.
Based on the results of the comparison of two VOC analysis platforms: SPME (Solid Phase Micro-Extraction) and TD-GC-TOF-MS (Thermal Desorption-Gas Chromatography-Time of Flight- Mass Spectrometry), the work was carried out entirely using the more sensitive TD-GC-TOF-MS. Baseline libraries of VOCs created for melon and rocket were used in the analysis of several independent experiments on the two fresh-cut species:1. Storage conditions
(a) Effect of storage at two temperatures (4°C and 20°C) for up to 14 days on fresh-cut melon and rocket salad (with Universidade Catholica Portuguesa (UCP)and University of Milano (UMIL))
(b) Effect of post-harvest-related abiotic stresses (cold, dark, wounding) on fresh-cut rocket (with UMIL)
2. Effect of different levels of processing (comparison of cut size, 1.0 x 1.0 cm2 or 2.5 x 3.5 cm2) in fresh cut melon (with UCP)
3. Detection of contamination with Listeria monocytogenes (cubes inoculated with 106 CFU and stored for 0, 3 or 5 days at 20°C or 0, 4 or 14 days at 4°C compared to un-inoculated melon cubes) in fresh-cut melon cubes (with Agricultural University of Athens).
Scientists have identified markers (groups of compounds) that are useful:
1. for assessing storage period and temperature for fresh cut melon and rocket salad;
2. for processing (cut size) melon;
3. as indicators of abiotic stress occurring immediately postharvest for rocket salad;
4. as indicators for Listeria monocytogenes contamination in melon.