The use of synthetic foods to optimise microwave-assisted digestion procedures

Major food constituents such as proteins, fats and carbohydrates are genera lly recognised as having a strong influence on the performance of acid samp le digestion. Various Scheffe mixture experimental designs were used to det ect the influence and the interactions between these constituents during th e Kjeldahl nitrogen digestion using focused microwaves. Pure ingredients we re mixed in different proportions in order to prepare 7 synthetic food samp les covering a wide range of foods types. 3 hearing powers were applied and nitrogen recovery yields were recorded at different times. Two types of mo dels were proposed to describe the data: one that explains the shape of the recovery profiles. the other that gives the response surfaces of the recov ery yield as a function of digestion time. From these models precise guidel ines to optimise the digestion program of a given food can be deduce.