Polyphenols are compounds contained in the grape peel and their presence in wine depends on the wine-making technique. Phenolic compounds produced by grapes play an important role in the characterization of different red wines, not only because they determine their color, but also because they significantly influence their fragrance and above all taste. The polyphenol content along with the “chromatic profile” of a wine provides very useful elements to asses the genuineness and quality of a wine.
The Analyzers CDR WineLab® for determining Polyphenols in Wine and Must
The system is supplied pre-calibrated and ready for use.
Results are expressed in accordance with the reference method.
It is also possible to standardize the system using samples with a known titration.
The reagents have a shelf-life untill 18 months
The analytical methods are simple: the system does not require an equipped laboratory or skilled staff.
 CDR WINELAB® |
 CDR WINELAB® JUNIOR |
|
|---|---|---|
| Analyses | Wine and Must: Alcohol by Volume Acetic acid (volatile acidity) Fermentable Sugars Total Acidity L-Lactic Acid L-Malic Acid Free sulfur dioxide Total sulfur dioxide Yeast Assimilable Nitrogen (YAN) Gluconic Acid Acetaldehyde (Ethanal) pH Total Polyphenols Index Glycerol Colour (tonality and intensity) Total Polyphenols Total Anthocyanins Polymerised Anthocyanins HCl Index Tannins Catechins Copper |
Configuration with tailored panel of analyses |
| Simultaneous Sample Analyses | 16 | 3 |
| Multiple Analyses on a Sample |  |
– |
Method
Test type: End Point.
Time testing: one test 5 minutes – 12 Test/Hour.
Are possible test sessions with several samples, up to a maximum of 16.
Calibration curve
The calibration curve of CDR WineLab®, obtained using reference methods.
Test Principle
Polyphenols + Chromogen 
Oxidized polyphenols + Reduced chromogen
Polyphenols are placed in contact with a colored complex in an alcoholic solution and oxidized, thus discoloring the complex. Discoloration, measured at 630 nm (end-point), is directly proportional to the concentration of polyphenols in the sample and expressed in mg/L of gallic acid.
Reagent test Kits
The reagents are packaged in foil pouches containing 10 tubes useful to perform 10 analyses.
This is the minimum package that allows the use of CDR systems even to those who need to make a few analyses, thus not wasting reagents.
There are also boxes of 100 tests, however, packaged in 10 bags of 10 tubes containing the reagent.
Code. *300488: 10 tests
Code. *300485: 100 tests (10 packages of 10 tests)
The reagents have a shelf-life of 12 months.
Processing – Sample Volume – Measuring Range
Wine: use as is.
| Test | Measuring range (mg/L of gallic acid) |
Resolution | Repeatability |
|---|---|---|---|
| Poyphenols in wine | 150 – 3300 | 0,01 mg/L | 10 mg/L/td> |
For sample with values > 3300 mg/L, use half of the volume of the sample (5 µL) and multiply the result by 2.
