The composition, microbiology and biochemistry of semi-hard cheeses flavoured with native mint, lemon myrtle and bush tomato (BT) were compared with unflavoured (control) cheese during a 90-day period of maturation. Moisture, protein and salt levels of all cheeses were similar and did not change during maturation. However, the fat content of control cheese was significantly higher than that of the flavoured cheeses while the pH of cheese flavoured with BT was consistently lower throughout maturation. Total viable organisms, Lactobacillus and Lactococcus counts were between 106 and 107 colony forming units (cfu)/g cheese for all cheeses. Yeast and mould count was <102 cfu/g cheese throughout the maturation of all cheeses except in the cheese flavoured with BT which was >103 cfu/g cheese. Biochemical indices of proteolysis and lipolysis increased with the extent of maturation in all cheeses but were most pronounced in the BT-flavoured cheese. The capillary electrophoretic profile of this cheese also indicated a more extensive hydrolysis of both ' s- and ÃŸ -caseins. The microbiological quality of BT appeared to have exerted a very significant influence on cheese properties.