The Maillard reaction during the ripening of Manchego cheese

The Maillard reaction was studied in semi-industrial Manchego cheese during ripening, through measurement of furosine and galactose. An accumulation of galactose was observed during the initial period of ripening, probably due to the inability of Streptococcus thermophilus to metabolise galactose. However, a considerable decrease in galactose content and increase in furosine amount were found after 15 days of ripening. No further formation of furosine was observed after 45 days. This fact could be attributable to the exhaustion of galactose due to its participation in Maillard reaction and/or its utilisation by the microorganisms Lactococcus and Lactobacillus. Furosine seems to be a useful indicator of the Maillard reaction during ripening of Manchego cheese.