The USP Food Fraud Database categorizes the type or nature of food fraud reports as follows: replacement, addition and removal. Here is what those categories mean.
Replacement is the complete or partial replacement of a food ingredient or valuable authentic component with a less expensive substitute in an effort to evade standard quality control measures. Replacement typically involves product dilution or extending an authentic ingredient by adding one or more adulterants. An example is adding water and citric acid to lemon juice to fraudulently increase the titratable acidity of the final juice product.
The replacement category also includes false declarations of the geographic, species, botanical or varietal origin of a food. Examples are substituting less expensive cow's milk for goat's milk, misrepresenting a food's origin to evade taxes or tariffs and labeling a synthetic ingredient as "natural."
Addition involves adding small amounts of a non-authentic substance to mask an inferior-quality ingredient. An example of spice fraud is adding color additives to paprika to enhance poor-quality materials.
Removal is taking out an authentic and valuable constituent without the buyer knowing. An example is removing non-polar constituents such as lipids and flavor compounds from paprika to produce paprika-derived flavoring extracts. It's fraudulent to sell the resulting "defatted" paprika, which lacks the valuable flavoring compounds of normal paprika.