This website was created to centralize important information regarding the methodology to attribute nutrition values to the foods listed in the different datasets.
Here we can share our discussions and relevant files to document the process and serve as an archive for future improvements in the datasets. The key aspects that will be discussed in the next few months include:
For the SUA data, it was decided initially that we will prepare four regional tables: (1) Default table, based mainly on data from the USDA database; (2) a regional table for African countries; (3) a regional table for Asean countries; and (4) a regional table for Latin America.
To assist on the selection of the FCT/FCDBs for use, the group agreed that the new FAO/INFOODS Evaluation Framework should be used as a criteria to assess the quality of potential FCT/FCDBs.
Thus, some FCT/FCDBs where suggested by the team and assessed according to the eight screening questions available in the FAO/INFOODS Evaluation Framework. If the score for a certain FCT/FCDB is >100 it can be considered as a possible source of data for the Nutrient Conversion Tables that will be prepared to convert the data from SUA and HCES datasets.
NOTE: The only exception is the Indian Food Composition Tables (score = 90). Even though the score below FAO/INFOODS recommendations, it will be selected for use since it fits to the purpose of the project. The points lost were due to: data is not available in Excel; it includes raw foods only; food description is incomplete (but we can also use the pictures to complement).
Quality assessment of selected FCT/FCDB using the screening questions of the FAO/INFOODS Evaluation Framework.
How to evaluate the quality of food composition data and food composition tables?
Edible portion (EP) represent the parts of food item that can be eaten, after removing any inedible portions (e.g. seeds, peel, shells, bone and skin). The portion of the food that is inedible is called the “refuse”. Since the whole amount of food available for consumption is recorded in the SUA and HCES datasets and many foods contain an inedible part, this must be taken into account in the calculation of the nutrients available in the food supply. If the weight of the inedible part of the food is not subtracted, supply of nutrients in the foods would be overestimated. The refuse portion is expressed as a percentage (or as a coefficient) of the total weight of the item as purchased or produced, and is used to compute the weight of the edible portion.
The edible factors prepared by ESN in 2012 will be revised and will be applied to SUA/fish and HCES data.
However, it is important to note that for some foods reported in the SUA list, two different types of edible portion will be needed:
For more specific issues on the attribution of the EP coefficients, please refer to the document “Establishing default edible coefficients – specific situations“
The Nutrient Conversion Tables will include energy (kcal and kJ), water, total protein, total fat, available carbohydrates calculated by difference, total dietary fiber, alcohol and ash. Energy and available carbohydrates will be calculated according to the following formulas:
Note 1: if the value calculated for CHOAVLDF is negative (<0), it should be set to 0 (zero) before calculating the energy. For further derails please refer to the item “Assumptions for specific foods and components“)
Note 2: the sum of proximate components (SOP) as presented in the original sources and in the final foods should be used as a quality control. If the SOP is outside the acceptable range (95-105) the data for the given food should not be used.
Minerals and vitamins will be selected according to the following criteria:
To assist the evaluation of the FCT/FCDBs regarding item 1, an Excel file listing the main components included, according to the different tagnames was prepared for the FCT/FCDBs selected according to the quality score (available for download in “references and files” below).
Significant digits and decimal places for each component in the nutrient analytical file and for presenting the statistics
The number of significant digits will be based on Greenfield and Southgate (2003), and the number of decimal places will be based on the criteria used in the FAO/INFOODS FCT for Western Africa. An excel file with this information is also available here.
This file list the main components included, according to the different tagnames, in selected FCT/FCDBs.
This file lists the number of significant digits and decimal places to the nutrient analytical file and for presenting the statistics
The importance of component identification; key aspects to check before using food composition data; using the FAO/INFOODS component identifiers (tagnames) for a precise identification
The excel file includes a couple of examples for each methodology. You can download the file to check how we should proceed in each methodology and also to have an idea about the impact in the results. In the video below you will find some details about this file.
Methodologies to convert food amounts into nutrients (with examples)
INFOODS developed these guidelines for a more harmonized approach to food matching while pointing out critical steps and information in order to achieve the most appropriate food matching. These guidelines are intended to assist in selecting the most appropriate foods (for which compositional data are available) to match to foods reported in food consumption surveys (at individual, household, national or international level) or to food supply data (e.g. FAOSTAT, EUROSTAT).
Definition and challenges; FAO/INFOODS guidelines for Food Matching
Created by Fernanda Grande (2021). The content of this website is continuously reviewed and updated.
Last updated 17.05.2021