Kinetic Assessment of High Pressure Inactivation of Different Plant Origin Pectinmethylesterase Enzymes

Abstract

High pressure can be applied for the inactivation of endogenous enzymes detrimental to fruit and vegetable products. One of the enzymes that affect the quality of fruits and vegetables is pectinmethylesterase (PME), responsible for cloud destabilization and consistency changes. Depending on the desired quality of the developed product, PME can be partly or fully inactivated. In this review paper, the cited results in the literature of the high pressure inactivation of PMEs in model systems after extraction and purification as well as in real food systems is comprehensively presented. It is discussed that the pressure stability of PMEs can vary significantly, especially when comparing the more pressure-sensitive types, like orange juice (Valencia cv.) PME, with the more barotolerant ones like purified banana PME (Cavendish cv.). This variation can be attributed to the type of enzyme, the coexistence with other enzymes, type of substrates, ionic strength, pH and nature of the medium in which the enzyme is dispersed. This review may support the systematic evaluation and optimal design of fruit and vegetable product high pressure (HP) processing aiming to control their shelf-life, especially when considering that milder conditions are necessary for the inactivation of microorganisms compared to endogenous enzymes. Using literature data, an exponential mathematical model was uniformly applied to enable a better comparative assessment of pressure effects, on all PMEs discussed in this manuscript, obtained from different plant sources.