The ripening of Emmental cheese samples from 30 dairies Ir as followed over I? months. Biochemical, chemical, microbiological, rheological and sensory properties were measured. Only a few parameters measured at 1 and 20 d could predict flavour and texture development after 3, 6 and 12 months. The sum of free amino acids measured after 1 d with the Cd ninhydrin method correlated with the index of maturity intensity of aroma, saltiness and sourness from 3 months. The TCA-soluble nitrogen (TCA-SN) after 20 d allowed the same prediction. Lysine aminopeptidase (LAA) after 20 d correlated positively with the index of maturity and saltiness after 3 months, and negatively with sweetness at 3 months and bitterness after 1 y. Higher proline aminopeptidase (PAA) values after 20 d were a good indicator for a pronounced sourness after 3 and 6 months. The higher the content of free amino acids after 1 d, the lower the firmness, stress and strain at fracture (up to 6 months). Strain at fracture could also be estimated by PAA after 1 d, LAA or TCA-SN after 20 d. All correlations were negative. Stress at 33% deformation correlated positively with LAA (up to 6 months) and TCA-SN (up to 12 months) after 20 d. (C) 1999 Academic Press