An insight on the relationship between food compressibility and microbial inactivation during high pressure processing.

This paper investigates the effect of high pressure liquid food compressibility on S. cerevisae inactivation. Honey with various adjusted sugar with different values of compressibility was selected as a model food. S. cerevisiae cells in different honey concentrations (0-80°Brix), 600 MPa (at ambient temperature) showed an increasing resistance to inactivation with increasing °Brix. D-values of S. cerevisiae at 200, 400 and 600 MPa, for 20 min/80°Brix were 136.99 ± 7.97, 29.24 ± 6.44 and 23.47 ± 0.86 min, respectively. These D-values resulted the Z p -value of 526 ± 39 MPa. A significant correlation (p < 0.05) of cell reduction, °Brix and compressibility was found. Cell reduction in high pressure-treated samples varied linearly with °Brix suggesting that the baroprotective effect of the food was not solely due to sugar content, but also due to its compressibility. This research could have significant implications on the success of HPP (high pressure processing) preservation of foods containing high sugar content.