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Folin-Ciocalteu Assay
•
Developed by Folin and Denis 1912 to measure tyrosine
•
Originally developed as an analysis for protein by Folin in
1927
WO
4
2‐
/ MO
4
2‐
+ Tyrosine –OH Blue color
•
Folin‐Ciocalteu (1927) added Lithium Sulfate and Bromine
to reaction mixture to prevent precipitate formation
•
Adopted for phenolics in wine by Singleton 1999
Folin-Ciocalteu Assay
•
Reduction of phosphomolybdic‐phosphotungstic acid (Folin)
t t bl
l
d l i
lk li
l ti
i
reagen o a ue‐co ore comp ex n an a a ne so u on occurs n
the presence of phenolic compounds.
•
The Folin ‐Ciocalteu Ciocalteu reagent reagent is not specific
specific and detects all phenolic groups found in extracts including
those found in the extractable proteins.