Tannins are generally defined as naturally occurring polyphenolic compounds of high enough molecular weight to form complexes with proteins.
Tanniniferous trees and shrubs are of importance in animal production because they can provide significant protein supplements, but unfortunately
the amounts of tannins that they contain vary widely and largely unpredictably, and their effects on animals range from beneficial to toxicity and
death. In addition, the toxic or antinutritional effects tend to occur in times of stress when a very large proportion of the diet is tanniniferous
and, therefore, measurement of tannin concentration in these materials is critical.
Methodologies for the analysis of tannins include chemical methods, approaches based on protein precipitation or binding, and bio-assays.
