Dielectric and microstructural properties of high-pressure treated hummus in the selected packaging materials

Hummus is a popular dip of the Middle Eastern countries and widely sold in the supermarket. The consumption of hummus from these sources could be a potential source of microbial contamination and food-borne diseases. In this work, the hummus samples were subjected to high-pressure treatment (300-600 MPa for 15 min) in three selected packaging materials (coextruded LLDPE, LLDPE and polylactide/essential oil blend) followed by measuring the dielectric properties and microstructure of the post-process samples. The hummus sample showed a significant change in the dielectric properties above 300 MPa. The packaging materials had the least effect on the dielectric parameters of hummus except for the biodegradable packaging, which showed a significant change compared to others. The ingredients influence the dielectric properties and microstructure of the sample. The selected test organism Listeria monocytogenes was completely inactivated by the pressure treatment at 400 MPa to ensure the safety of the product. Therefore, the HP treatment above 400 MPa could improve the safety of the product with retaining the desirable quality attributes.