Describes two methods as follows. Method A is an analytical procedure for the determination of the monomers 1,2-DHB, 1,3-DHB and 1,4-DHB in the food simulants water, 3% w/v aqueous acetic acid, 15% v/v aqueous ethanol and olive oil. Method B is an analytical procedure for the determination of DHBphen and DHBiph in the food simulants water, 3% w/v aqueous acetic acid, 15% v/v aqueous ethanol and olive oil.