Dear Tayo
You are posing the “million dollar” question, I think we all are concerned with when starting sampling foods for analysis J
I agree with Ruth’s answer to you, but I would like to elaborate a little more on the answer to you.
As the term “processed food” may include some ambiguity, For your purpose instead of distinguishing between raw and processed foods, I think it is better to distinguish between the following three levels
- Raw agricultural commodity level (foods as raw commodities)
- Ingredient level (foods as ingredients/purchased/raw)
- Consumption level (foods as eaten/prepared)
In your (the scientist’s) case there is also a potential build-in conflict in the purposes of the study:
- for food control purposes toxicity risk assessment (pesticide residues, toxic substances , etc.) is usually/normally carried out using data on raw commodities, i.e. edible and non-edible part, especially in food control; however total diet studies operate on the ingredient level/consumption level
- nutritional adequacy estimation is usually carried out using data on foods as eaten, i.e. the edible (prepared) part
Similarly, the kind of food intake data the scientist have available will have an influence on the need for compositional data (occurrence data).
The best is to have food consumption data for individuals, but such data are not always available. You do not say what food consumption data, you have available.

As Ruth indicates, nutrients are usually/best analysed on the ingredient level, e.g. as purchased/raw foods, and the nutrient content can be calculated using algorithms including yield and nutrient retention factors.
For pesticides and contaminants, the situation may be slightly different, if your risk assessment is based on food control issues – then only raw agricultural commodities need to be analysed. If you need to make a risk assessment on pesticides and contaminants including all foods in the diet, your situation is a bit different.
Like for nutrients, there are models for recalculating pesticide and contaminant data between the different levels. This recalculation include so-called processing factors.
Hope that this helps you a little.
All the best,
Anders
Anders Møller
Danish Food Informatics
Borgediget 12
DK-4000 Roskilde, Denmark
Websites: Danish Food Informatics (http://www.danfood.info)
SciName Finder™ (http://www.sciname.info)
LanguaL™ (http://www.langual.org)
From: Food Composition Discussion Group [mailto:[log in to unmask]] On Behalf Of Tayo Shokunbi
Sent: 31 July 2014 08:40
To: [log in to unmask]
Subject: Which is the better option
Dear Colleagues,
In this era of limited resources for researches in the developing countries, what will be your advice to a scientist faced with the need to make a choice between analysis of RAW or PROCESSED foods? He needs the data obtained from the analysis for TOXICITY risk assessment as well as assessment of a populace for ADEQUACY of nutrient intakes.
Best regards
Shokunbi, OS (MSc)
Biochemistry Department, Benjamin Carson School of Medicine,
Babcock University, Ilisan Remo,
Ogun State, Nigeria.
+2348030689633.
To unsubscribe from the InFoods-Food-Comp-L list, click the following link:
https://listserv.fao.org/cgi-bin/wa?SUBED1=InFoods-Food-Comp-L&A=1
To unsubscribe from the InFoods-Food-Comp-L list, click the following link:
https://listserv.fao.org/cgi-bin/wa?SUBED1=InFoods-Food-Comp-L&A=1