Abstract

Hyperbaric storage ( HS ), storage under pressure at 25°C and 30°C, of a ready‐to‐eat ( RTE ) soup was studied and compared with refrigeration. Soup was stored at different time (4 and 8 h), temperature (4°C, 25°C, and 30°C), and pressure (0.1, 100, and 150 MPa) conditions, to compare microbial loads and physicochemical parameters. HS resulted in similar (microbial growth inhibition) to better (microbial inactivation) results compared to refrigeration, leading to equal and lower microbial loads, respectively, at the end of storage. Lower/higher pressure (100 vs. 150 MPa) and shorter/longer storage times (4 vs. 8 h) resulted in more pronounced microbial growth inhibition/microbial inactivation. Aerobic mesophiles showed less susceptibility to HS , compared to Enterobacteriaceae and yeast and molds. HS maintained generally the physicochemical parameters at values similar to refrigeration. Thus, HS with no need for temperature control throughout storage and so basically energetically costless, is a potential alternative to refrigeration.

The possibility of food hyperbaric storage ( HS ) at and above room temperature is a new research field with potential to replace refrigeration as a new preservation technology. Is has been showed the feasibility of HS as an energetically quasi costless, as well as, quasi environmentally footprintless food preservation technology, because once the pressure is generated no more energetic costs are associated to this process, it uses only water (which is recycled) as pressure medium, and has no need for temperature control (contrarily to refrigeration). This technology practical implementation requires a whole new range of pressure chambers, able to resist pressure levels lower than the currently used pressure pasteurizers, but for longer periods. It should be kept in mind that before thinking in practical applications (whether in industry, retail, etc.) the method feasibility and potential has to be studied. With the present paper we aim to contribute for this, with a case study on soup.