The present invention provides an apparatus and methods for producing tetrahydrocannabinolic acid (THCA), cannabichromenic acid (CBCA) and cannabichromenic acid (CBCA) in different ratios. The apparatus comprises: (i) a bioreactor comprising (a) an automated supply system configured to deliver a first automated supply of cannabigerolic acid (CBGA), a cannabinoid acid synthase, and a reaction mixture; and (b) a second automated system to cease the reaction; (ii) a controller configured to modify a property of the reaction mixture to produce the desired products; and (iii) an extractor configured to recover the tetrahydrocannabinolic acid (THCA), cannabichromenic acid (CBCA) or cannabidiolic acid (CBDA) and cannabichromenic acid.