Foods like cassava are often subjected to processing before consumption, which after the retention of the carotenoid. i want a clear cut explanation on how to calculate the true retention. from what i have seen so far,the formular given is always higher with no concrete explanation. how do we go about this?

also i need to know the effect of fermentation on carotenoid retention in cassava especially

Here are some sites that go into it in great detail:

cat.inist.fr/?aModele=afficheN&cpsidt=21189255

www.fasebj.org/cgi/content/meeting_abstract/23/1.../896.7