High-pressure processing of freshly cut vegetables: influence on organoleptic properties, microbial load and trace...

The demand for minimally processed foods has increased markedly over the past two decades. Two varieties of freshly cut vegetables (rocket and spinach), as fresh and freeze-dried vegetables, were treated by high-pressure (HP) processing. The time and pressure values tested were 2 min for 200, 400 and 600 MPa; and additionally 4 and 5 min for 200 MPa.

The scores from sensory analysis of fresh rocket and spinach were uniformly low across all evaluated attributes, resulting in the sensory data being inappropriate to find a positive effect of the HP treatment on the fresh vegetables. Nevertheless, freeze-dried rocket and spinach exhibited a significantly greater resilience to HP treatments, maintaining acceptable sensory attributes. HP treatments demonstrated a clear impact on reducing microbial loads in rocket and spinach leaves. For both matrices, pressures of 400 MPa and above applied for 2 min led to reductions in aerobic mesophilic bacteria compared to untreated controls. Finally, HP treatment did not produce significant modification in trace element bioaccessibility of vegetables studied.

The application of HP treatment on the fresh cut vegetables studied (rocket and spinach) showed that it is not an effective technology when these vegetables are presented in fresh form. In contrast, HP treatment was more effective from an organoleptic point of view on these vegetables in freeze-dried form. Regarding the reduction of the microbial load, intensive treatments (above 400 MPa) are necessary to find a significant effect. Finally, HP treatment did not affect the trace element bioaccessibility. © 2026 Society of Chemical Industry.