Kinetic study on unsaponifiable fraction changes and lactose hydrolysis during storage of Mozzarella di Bufala Campana PDO cheese

Abstract

Cholesterol, vitamin E and vitamin A isomers, components of the unsaponifiable fraction, and lactose contents in Mozzarella di Bufala Campana PDO cheese have been studied during storage in different conditions: at 6–8°C, and at room temperature (traditional habits). During cold storage there were no significant differences in the unsaponifiable compounds, while during storage at room temperature an increase of the 13-cis isomer and a decrease of all-trans-retinol were observed. Trans/cis-retinol isomerization, expressed as the Degree of Retinol Isomerization (13-cis/all-trans%) showed an increase in all samples during storage at room temperature following a linear correlation. The decrease of lactose content during storage was studied by a first-order differential relaxation equation. Apart from the traditional habits, consumers should be aware that, during storage at room temperature, the most important changes in the considered nutrients occur. These changes can be negative (vitamin A reduction) but also positive (lactose reduction).