http://www.synbioproject.tech/cpi/applications/saffron/
Saffron is the world’s most expensive spice, as well as one of the oldest. The characteristic saffron flavour, colour and odour come from several components, of which the most important are picrocrocin, crocin and safranal. All of these are present in stigma of the Saffron crocus. This same spice is under development to be produced with genetically modified yeast fermentation techniques. Source
Genetically modified yeast fermentation.