1. Identifying & Updating Tunisian’s Key Foods list for Food Composition Database
Pr Jalila EL ATI (Tunisia) & Dr Eric VERGER (France)
with collaborators from:
Tunisia (Radhouene Doggui, Chiraz Beji, Houda Ben Gharbia, Samia Cherif,, Asma Bahrini, Tarek Trabelsi)
France (Pierre Traissac, Edwige Landais, Francis Delpeuch, Claire Mouquet-Rivier, Marie-Claude Dop)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

2. Brief History on FCT in Tunisia
1954: 1st FCT from analysis of some vegetables (tomato, pepper, onion, potato)
1974: 2nd FCT from analysis of few cereals, nuts, legumes, fruits, vegetables
1975: 3rd after compilation from local and international food composition database by experts from FAO/INS. 240 food items (raw and cooked).
2004: update the FCT as one of the deliverables of the European project (TAHINA)
2006: Edition of the 4th CFT for use in Tunisia
2018: Finalising the 5th CFT for Tunisian use
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

3. Brief History on FCT in Tunisia
1954: 1st FCT from analysis of some vegetables (tomato, pepper, onion, potato)
1974: 2nd FCT from analysis of few cereals, nuts, legumes, fruits, vegetables
1975: 3rd after compilation from local and international food composition database by experts from FAO/INS. 240 food items (raw and cooked).
2004: update the FCT as one of the deliverables of the European project (TAHINA)
2006: Edition of the 4th CFT for use in Tunisia
2018: Finalising the 5th CFT for Tunisian use
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

4. Brief History on FCT in Tunisia
1954: 1st FCT from analysis of some vegetables (tomato, pepper, onion, potato)
1974: 2nd FCT from analysis of few cereals, nuts, legumes, fruits, vegetables
1975: 3rd after compilation from local and international food composition database by experts from FAO/INS. 240 food items (raw and cooked).
2004: update the FCT as one of the deliverables of the European project (TAHINA)
2006: Edition of the 4th CFT for use in Tunisia
2018: the 5th CFT for Tunisian use is being finalized
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

5. Key foods list: Overview of the procedure
The Key Foods approach developed by the United States Department of Agriculture (USDA) was used:
Combination of:
1. Data on national consumption foods and beverages
AND
2. Existing nutrient composition
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

6. Key foods list: Overview of the procedure
A scoring system to rank the foods and identify “Key Foods”
Key Foods =
Foods that contribute to the diet with significant amounts of nutrients of public health interest
We need:
National food consumption data
AND
list of food nutrients of public health interest
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

7. Key foods list: Overview of the procedure
1. National food consumption data
The National nutrition surveys
1996
Cross-sectional survey based on a national stratified two-level stage sample
Conducted by the National Institute of Nutrition and Food Technology
Representative sample of households (n= 1800); 7218 subjects, age 2 – 80 years
3-day food record (two weekdays and one weekend day‎)
everything they ate and drank was reported and household utensils, food photographs or models are used for estimating portion size
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

8. Key foods list: Overview of the procedure
1. National food consumption data
The National nutrition surveys
1996
2005
Cross-sectional survey based on a national stratified three-level sample
Conducted by the National Institute of Nutrition and Food Technology
Representative sample of households (n= 7500); 7350 subjects, age years
Validate quantitative food frequency questionnaire over a 1-month period
Household utensils, food photographs or models are used for estimating portion size
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

9. Key foods list: Overview of the procedure
1. National food consumption data
The National nutrition surveys
1996
2005
The National on the budget, food consumption and living conditions of households
2015
Conducted by the National Institute of Statistics
Representative sample of households (n= 13000)
7-day weighed food records method is used twice a year
Each consumed food is weighted prior to consumption and recorded in a booklet
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

10. Key foods list: Overview of the procedure
1. National food consumption data
The National nutrition surveys
1996
2005
The National on the budget, food consumption and living conditions of households
2015
2. List of nutrients with public health interest
Energy, proteins, fats, saturated fats, iron, calcium, sodium and fiber
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

11. Key foods list: Overview of the procedure
Example: the foods list from the national survey of 2015
1. The average nutrient contribution from each food (column C) is calculated by multiplying the average intake of the food item (column B) with the content of the key nutrient (column A)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

12. Key foods list: Overview of the procedure
Example: the foods list from the national survey of 2015
2. Divide nutrient consumed for each food by total quantity of nutrient consumed for all foods to calculate nutrient contribution in percent (column D)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

13. Key foods list: Overview of the procedure
Example: the foods list from the national survey of 2015
3. Cumulative percentage is calculated and foods are ranked in descending order according the cumulative percentage (column E)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

14. Key foods list: Overview of the procedure
Example: the foods list from the national survey of 2015
4. Key foods are defined as those foods that contribute at least by 75% of the intake of the key nutrients.
Example Total Fats:
from a list of 182 food items, 9 are Key foods
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

15. Key foods list: Overview of the procedure
Example: the foods list from the national survey of 2015
4. The procedure is repeated for all key nutrients.
Of the 182 food items, only 38 are Key foods, contributing by 75% of food intake
38 Key Foods
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

16. Management of food composition data Examples from the MEDINA project
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

17. 1 – Including wild food in the Tunisian food composition database
Need to include new food items in the Tunisian food composition database
Wild food usually consumed in the Sidi Bouzid Governorate have been identified during an ethnobotanical study
Lack of information about these foods in the Food Processor Software which constitute the core of the Tunisian food composition database
Need to include new information into the database while respecting its current format
 nutritional values for energy and 27 nutrients : protein, available carbohydrate, sugar, free sugar, fiber, total fat, SFA, MUFA, PUFA, vitamin A, thiamin, riboflavin, niacin, pantothenic acid, vitamin B6, folate, vitamin B12, vitamin C, vitamin E, calcium, copper, magnesium, zinc, phosphorus, potassium, iron and sodium
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

18. 1 – Including wild food in the Tunisian food composition database
The process in a nutshell
Consider the primary sources of the data
Compile and select the best information
Compile and check data 1 2 3
Illustration with the case of wild fennel
(Besbes arbi)
Source: Greenfield & Southgate Food composition data - production, management and use. FAO, Rome.
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

19. 1 – Including wild food in the Tunisian food composition database
Consider the primary sources of the data (1/2)
3 samples of wild fennel (2 from local market and 1 from irrigated farm)
Fibrea : Lee, Prosky et al, 1992 (AOAC )
Carotenoidsa : HPLC (Taunbodhitham et al, 1998)
Folatea : microbiological method (Kariluoto & Piironen, 2009)
Vitamin Cb : HPLC (Fontanaz et al, 2006)
Mineralsb : atomic absorption spectrometry (Hama et al, 2011)
Common name
Scientific name
Dry matter
(g/100g)
Fibre
βcarotene*
(μg/100g)
Folate
Vitamin C
(mg/100g) Fe Zn
Calcium K
Wild fennel leaves
Anethum graveolens
18.1
6.5
5908
172
42.9
1.8
0.4
252
475
a assays done in triplicate; b assays done in duplicate; * α-carotene and β-cryptoxanthin were absent in the samples
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

20. 1 – Including wild food in the Tunisian food composition database
Consider the primary sources of the data (2/2)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

21. 1 – Including wild food in the Tunisian food composition database
Compile and select the best information
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

22. 1 – Including wild food in the Tunisian food composition database
Compile and check data (1/2)
Keep records
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

23. 1 – Including wild food in the Tunisian food composition database
Compile and check data (2/2)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

24. 1 – Including wild food in the Tunisian food composition database
Checks on components
Check Proximate
95 ≤ Water + Ash + Protein + Fat + Total Carbohydrates ≤ 105
Check Fat
Total Fat - (SFA+MUFA+PUFA) ≥ 0
Check PUFA
PUFA - (n3+n6) ≥ 0
Check Ash
Ash - (Calcium + Copper + Iron + Magnesium + Phosphorus + Potassium + Sodium + Zinc) ≥ 0
Check Vit A
Vitamin A RAE = (Retinol) + (Beta-carotene/12)
Many other checks available in the document FAO/INFOODS Guidelines
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

25. 2 – Calculation of the composition of dishes prepared from recipes
Need to calculate the food composition of dishes collected in the MEDINA Study
Food intakes of women assessed by a 24-h recall conducted by trained personnel, every three months over a year
Detailed recipes for dishes (e.g. couscous with wild fennel and traditional soup) consumed by the women
Portion sizes of the foods, beverages and ingredients used in dishes were estimated using: booklet with photographs of calibrated portion sizes; extensive household measure; and weight indicated on packaged foods
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

26. 2 – Calculation of the composition of dishes prepared from recipes
Information on the quantity of ingredients and the cooking process
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

27. 2 – Calculation of the composition of dishes prepared from recipes
Three approaches for recipe calculation
Recipe calculation method
Yield factor
Retention factor
Total Recipe Method
recipe level
Mixed Method
ingredient level
Ingredient Method
Because the weight of the cooked dishes were not collected during the survey, we had to use the Ingredient Method, except for the soups.
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

28. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Assign a nutrient composition to each ingredient
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

29. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Assign the most relevant yield and retention factors to each ingredient according to the cooking method (Bognár 2002)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

30. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Estimate the final weight of cooked dish (sum the weight of each raw ingredient multiplied by the relevant yield factor)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

31. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Calculate the nutrient contribution of each ingredient to the final dish
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

32. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Sum the nutrient contribution of each ingredient to the final dish and calculate the energy content (optional: nutrient profile)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

33. 2 – Calculation of the composition of dishes prepared from recipes
Ingredient Method - Couscous with wild fennel
Compare with external data (e.g. French database)
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018

34. 2 – Calculation of the composition of dishes prepared from recipes
Mixed Method – Traditional soup
Very similar process with two exceptions:
The final weight of cooked dish is not estimated but measured (replication in laboratory)
The nutrient contribution of water (minerals) is taken into account
Workshop on standardized methodologies for food composition databases.
Ras Jebel, Tunisia, 5 – 8 November 2018