This diagram explores the apple tree food source to food product relationships: three different kinds of apple-related products are shown in relation to a food source organism (apple tree) and various food preparation and packaging processes.
The diagram below shows a few other kinds of food product and the various relations that FoodOn currently employs to connect them to raw food source organisms. On the left side an organism has undergone some food transformation process, for example, harvesting, shipping, cooking, freezing, packaging, slicing. On the right side, a reference to an organism does not necessarily involve a food role context. No food transformation processes are implied in organism. For example, “apple tree” with respect to some plant disease does not require us to consider the tree with respect to food products.
FoodOn uses the following relations.
- “has part” is used between entities of the same type, e.g. between anatomical entities, (e.g. “albumen” is part of an egg) or between proscriptive parts (e.g. “a pie has a crust and a filling”). A “part” often plays a functional role with respect to the whole.
- “has substance added” is an object property which can apply to any substance roles – chemical, physical, food, etc. It differs from “has part” because the added substance may not be discernible at a later time in the mixture or thing it was added to.
- “has ingredient” is a sub-property of “has substance added” pertaining just to a food domain and range. It is used to refer to a food substance added to a food product. If an ingredient is visually recognizable in a food it can also be a mereological part of the food, as in the apple and caramel parts of a caramel apple. Currently “has ingredient” is defined in FoodOn, not in the Relation Ontology.
- Use X “member of” Y to associate a food product with a product type category that is outside of the “foodon product type” branch (e.g. EFSA or GS1). By avoiding “is a” subclass-class axioms between FoodOn food products and agency food categorization hierarchies, we insulate to some degree FoodOn product type logic from any inconsistencies that arise from agency conjunctions or disjunctions of categories.
- X “develops from part of” Y can be used when X is a cellular structure that undergoes biological growth; the relation does not imply the elimination of Y, in fact many plants generate harvestable food through a growing season or across several years. In FoodOn, this is mainly applied to fruits, seeds, and vegetables like zucchini harvested from plants. (Anatomical ontologies may use this term in much greater detail.)
- Y “produced by” X is used when Y is a substance that does not undergo biological growth, like milk. Y may be available in a quantity that can be harvested for food. This includes body products like blood (see https://en.wikipedia.org/wiki/Blood_as_food)
- X “derives from” Y (an organism or organism part) is used when no more specific relation is yet available or curated; it often acts as shorthand for a more elaborate process model, if any. Note that the relation ontology “derives from” object property currently states that the entity Y ceases to exist as a result of the formation of X; in some cases this might be problematic if a product X uses only some component of Y.
- X “has food substance analog” Y allows two products to be linked when they have similar phenotypic properties or process roles.