| The main entities of a food data collection - Food |
It seems obvious that the Food entity is required and used to describe the foods in the
food composition table, the food composition database and any food
composition interchange package. The Food entity contains properties
(metadata) that describe the foods reported in the table or database -
often through the use of standard vocabularies or classifications.
Typically, the Food entity will
hold the food name in the local language - eventually also in
English. For foods of plant or animal origin it is important to provide
information about the scientific name of the plant or animal. The food
name may also hold short information about its state of preparation,
e.g. raw, boiled, fried, etc.
Food names are often regulated. It is therefore important that food
names used in tables or databases are compliant with the local or
regional regulations.
These issues are further explained in
Food Names.
Food identification in the food composition context usually refers to
a specific unique identifier - often called a food code - for each food in a food
composition table or database.
From a maintenance and database aspect, it is preferable that this
identifier is arbitrary with no specific meaning - in databases the
unique food identifier is usually of the type called autonumber,
a simple serial number.
As indicated, food identifiers should not contain any information but the code itself. It is a code that points to a specific food in a table
or database. Including other information in the code such as food classification (see below) or preparation method often leads to problems when wanting
to include a new classification or preparation method. At a certain point the chosen code format can no longer handle changes and a new set of codes need to be introduced.
Although there are examples of systems, where food classification
and/or description is embedded in the food identifier, there are several reasons why the food identifier is not
the right place to keep this kind of information. First of all, if there
are small changes in the classification or description, the food code
will change. Secondly, the code may become very long, if much
information is embedded in the code. It is better to keep the food
code/identifier clean, and keep the food classification/description in
other places ("fields") in the table of database.
In food classifications, foods are ordered/gathered in classes or groups according to specific
pre-defined criteria. Foods are classified into multiple categories to
construct order in complex food environment, and the order is
determining the final outcome of the food classification system. In the
first approach, a variety of food classification systems has been
developed. Some classifications have been formulated to describe food
habits, while others fulfill requirements set by regulatory bodies.
Classification systems are often standardized, as they may be based on
legal documents, the most standardized being "vocabularies".
This means that food classifications are purpose-driven, created for
a specific purpose and fit for use. A food classification system often
cannot be used for another purpose than the one it was designed for and
cannot be used for foods at all levels (foods as eaten, ingredients,
commodities).
Food description has a different purpose than food classification.
Where the classification system tends to class/group foods with specific
similar characteristics, the food description system is more oriented to
describe foods as detailed as possible. Consistent indexing and
retrieval can be attained using faceted thesauri (ISO, 1986), in which
vocabulary control is achieved by deliberately restricting the scope of
terms and through its display of hierarchical relationship. Due to its
flexible structure, such a vocabulary can be amended by adding new
viewpoints for food description or by including more details within
facets. A faceted thesaurus is thus well adapted to describe the
features of foods.
| Food classifications versus Food Description |
It is commonly useless to discuss what is best, food classifications or food description. Food classification and food description
are created for different, specific purposes and may have very different
goals, and this leads to very different appearances of the systems. A
classification system tends to group or aggregate foods with similar
characteristics; it is a tool of the "end-user" of data. A description
system, on the other hand, is a tool of the data originator, who wants
to give a description of the food, as precisely as possible, without the
necessity of aggregating them.
- International Standard ISO 2788 (1986):
Documentation- Guidelines for the establishment and development of
monolingual thesauri.
- International Standard ISO 5964 (1985):
Documentation- Guidelines for the establishment and development of
multilingual thesauri.
- Burlingame B.A. (1998):
Food Nomenclature and Terminology: Standards and Harmonisation for
Food Composition Databases and Food Trade.
16th International Congress of Nutrition, 1998.
- Ireland J.D., Møller A. (2000):
Review of International Food Classification and Description.
Journal of Food Composition and Analysis, vol. 13, pp. 529-538,
2000.
- Ireland, J.D. and Møller A. (2006):
Review of Food Classification and Description Systems for Use in
Food Composition Databases.
EuroFIR Deliverable D1.6.6a. - 23 May 2006.
- Wanda Polacchi:
Standardized Food Terminology: An Essential Element for Preparing
and Using Food Consumption Data on and International Basis.
Food and Nutrition Bulletin, vol. 8, no. 2.
The United Nations University, 1986.
- Pennington J.A.T.:
Food Classification and Terminology Systems.
Keynote address at First International Food Data Base
Conference.
Proceedings of the First International Food Data Base Conference, ,
Sydney, Australia, 22–24 September 1993.
AOAC International, 2nd ed., 2000.
- European Food Safety Authority (2011):
Report on the development of a Food Classification and Description
System for exposure assessment and guidance on its implementation
and use.
EFSA Journal 2011;9(12):2489
- European Food Safety Authority:
Food classification -
FoodEx2.
Website accessed 2014-05-08
Compilers' Toolbox™
