The symbiotic culture of acetic bacteria and yeasts immersed in the sweetened tea infusion triggers an alcoholic fermentation that can bring about variable alcohol concentrations from traces by approximately one percentage point.
Normally the majority of Kombuchas on the market have an alcohol content that is below 0.5%. The measurement of this parameter is very important for legal purposes as a concentration above 1.2% requires registration of the beverage produced as “alcoholic”.
CDR KombuchaLab: Instruments for the determination of Alcohol by Volume in Kombucha
The instruments are supplied pre-calibrated and ready to use.
The results are expressed according to the reference method.
The methods are simple: there is no need for an equipped laboratory or for specialist personnel.
 CDR KombuchaLab |
 CDR KombuchaLab Junior |
|
|---|---|---|
| Analyses | Kombucha: Alcohol by Volume Acetic Acid Fermentable Sugars Gluconic Acid Total Lactic Acid Yeast Assimilable Nitrogen (YAN) Glycerol Total Polyphenols |
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 6 minutes.
Analysis sessions with multiple samples are possible for up to a maximum of 16 tests for CDR KombuchaLab and 3 tests for CDR KombuchaLab Junior .
Correlation curve
The calibration curve of the CDR KombuchaLab instrument, obtained by comparing the CDR method with the distillation method for determination of the alcohol content, confirmed an excellent linearity of the system over the entire measurement range.
Test Principle
Ethanol, in the presence of NAD+ , is oxidized by enzymatic route to acetaldehyde with the consequent production of NADH. The increase in absorbance, measured at 366 nm at the end-point, is directly proportional to the concentration of lactic acid in the sample. The result is expressed in ppm.
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. *300665: 10 tests
Code. *300666: 100 tests (10 packages of 10 tests)
When a dilution is requested, you have to use an appropriate reagent kits:
Code *300666: The kit allows 10 dilutions
Code *300667:- The kit allows 100 dilutions (10 packages of 10 tests)
The reagents have a shelf-life of 6 months
Processing Sample
For precise and repeatable analysis on the must, the sample must be degassed with the appropriate ultrasonic bath and centrifuged (code 222062) with the mini-centrifuge (code 222061) to separate the solid particles present in the solution.
Measuring Range
| Test | Measuring range | Resolution | Accuracy |
|---|---|---|---|
| Alcoholic content | 0.1 – 1.8% vol. | 0.01% vol. | 0.02% vol. |
