Sage Derby (pronounced [ˈdɑːbɪ]) is a mild, mottled green, semi-hard cheese with a sage flavour. The colour is from sage and sometimes other colouring added to the curds, producing a marbling effect and the subtle herb flavour. The colour is from mixing sage leaves in the curd before it is pressed or by the addition of "green curd" from green corn or spinach juice. In the latter case, the flavour has to be created with colourless sage extract. The sage gives the cheese an almost minty flavour. Parsley, spinach and marigold leaves, bruised and steeped before use, can also be included instead of the sage leaves.
The first production began in the seventeenth century in England. Sage Derby was only made for festive occasions such as harvest and Christmas, but it is now available all year.