Laccase

Laccases (EC 1.10.3.2) are multicopper oxidases found in plants, fungi, and bacteria.

For example, laccases play a role in the formation of lignin by promoting the oxidative coupling of monolignols, a family of naturally occurring phenols.

[1][2] Other laccases, such as those produced by the fungus Pleurotus ostreatus, play a role in the degradation of lignin, and can therefore be classed as lignin-modifying enzymes.

[8] The type III copper can be replaced by Hg(II), which causes a decrease in laccase activity.

Laccases have the potential to crosslink food polymers such as proteins and nonstarch polysaccharides in dough.

[12] These cross-links have been found to greatly increase the maximum resistance and decrease extensibility of the dough.

Oxidation of the ferulic acid on AX to form ferulic acid radicals increased the oxidation rate of free SH groups on the gluten proteins and thus influenced the formation of S-S bonds between gluten polymers.

This was a result of the gas (carbon dioxide) becoming trapped within the crust so it could not diffuse out (like it would have normally) and causing abnormal pore size.

The high dosage may have caused extreme changes in the structure of dough, resulting in incomplete gluten formation.

[16] Laccase is produced by a number of fungal species that can infect grapes, most notably Botrytis cinerea Pers.