A SYSTEM FOR DEFINING REFERENCE MATERIALS APPLICABLE TO ALL FOOD MATRICES

Recently the subcommittee on Food Definition of the AOAC INTERNATIONAL Task Force on Methods for Nutrition Labeling proposed a ''Food Matrix Organizational System'' [4] to systematically judge the applicability of collaboratively studied methods over a range of food matrices. Thi s system describes a food matrix by its location in one of nine sector s in a triangle, with each point of the triangle defined as representi ng 100% and the opposite side representing 0% of the normalized conten ts of each of three major components of FAT, PROTEIN and CARBOHYDRATE. Foods falling within the same sector would be chemically similar and thus should behave in a similar analytical manner. This same scheme ca n be used to select one or two food matrices representing each sector, for development of a series of reference materials representing all f oods. The list of 5250 foods contained in the USDA Nutrient Data Base for Standard Reference has been sorted and matched to this schematic t o determine the scope of the selection process. In addition the list o f foods in the ''USDA Data Base for Food Consumption Surveys'' has bee n examined. Results and progress of this selection process are reporte d.