Online-calculator for volatile compound concentrations in standard solutions (OIV methods, ENG)

The first important step in implementation of OIV methods for alcoholic beverages analysis is the preparation of standard solutions (SS) and accurate calculation of certified values of volatile compounds concentration in the SS.

The web-program "Online-calculator" facilitates this stage and calculates the concentrations of compound in the SS prepared in the accordance of methods "OENO-SCMA 24-756 Et5_2026" (using contained ethanol as a reference standard, EIS method) and "OIV-MA-BS-14" (TIS method) in units µg/g and g per 100 L anhydrous ethanol (g/100 L AA).

Brief description of the methodology and "Online-calculator"

Methods EIS and TIS are suitable for gas chromatographic determination of the following volatile microimpurities in alcoholic and low-alcohol beverages, spirits, wine, wine products and alcohol-containing food products: aldehydes (ethanal (acetaldehyde)), esters (methyl ethanoate (methyl acetate), ethyl ethanoate (ethyl acetate)), acetal, methanol (methyl alcohol) and higher alcohols (2-propanol, 2-butanol, n-propanol, 2-methyl-1-propanol, n-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol) with analyte content ranging from 5 to 1500 g per 100 L anhydrous ethanol (g/100 L AA).

The new EIS method uses ethanol as an internal standard: ethyl alcohol is present in all samples and serves as a reference substance.

In conventional IS methods, traditional internal standard (TIS) is added to all samples. The TIS examples are: 3-pentanol, 1-pentanol, 4-methyl-1-pentanol, methylnonanoate, tert-amyl alcohol, n-amyl acetate, n-butyl acetate, n-pentyl acetate, 2-ethylbutyric acid, tetradecanol.

To prepare SS, use only reagents of a purity (P, %) greater than 97.0 %, with certificate of purity.

To work according to the both EIS and TIS methods, the following standard solutions (SS) of volatile compounds and internal standard (IS) are prepared:

To work according to EIS method only, the following standard solutions (SS) of volatile compounds are prepared:

• 40 % v/v ethanol solution in water (WES),
• stock SS-A,
• SS-B for establishing the calibration coefficients RRF,
• SS for the control of the FID response linearity - 0.1, 0.5, 1.0 (or 5), 2.0 (or 30),
• SS-QC for the checking of the calibration quality,

The required initial data for the calculator operation is:

• mass values of compounds added in SS,
• strength and density of water-ethanol solution (WES),
• chromatographic data of calibration standard solution (SS-C at simultaneous work by TIS and EIS methods or SS-B at work by only EIS method).

Jump to the "Online-calculator" (ENG)

There are three version of "Online-calculator" program: to simultaneously work with in TIS and EIS methods, to work by only EIS method at concentration up to 150 g/100L AA and to work by only EIS method at concentration up to 1500 g/100L AA.

The calculator has a "Main Menu" for navigation.

"Main Menu" navigation panel contains the link (versions 1, 2, 3) to pdf-file "GUIDE Calculation of Compound Concentrations in Standard Solutions and Calibration Factors during preparation the solutions in the accordance of the new OIV method OENO-SCMA 24-756 Et5_2026, using contained ethanol as a reference standard, (EIS method) and the OIV-MA-BS-14 method (TIS method)" of complete guide (ENG). Recommended reagent masses for preparing solutions are provided in this guide, as well as all the calculation formulas used in the web application.

	A copy of the online-calculator start screen is shown. A single button "Press to Submit Data" used to transfer user-entered data to the calculator. Calculation results can be saved as HTML, PDF, or downloaded in TXT format. An example of a completed and saved PDF file is here.
	Example of a downloaded data file *.txt
	The downloaded txt file can be easily opened in Excel.
	The data fields in *.txt files are separated by semicolons, so, select the semicolon as delimiter to open these files in Excel.
	Example of the file with results in Excel