METHOD FOR DETERMINATION OF ORGANIC OXY ACIDS ORIGIN IN WINES AND JUICE-CONTAINING BEVERAGES Russian patent published in 2013 - IPC G01N33/02 G01N33/14 

FIELD: food industry.

SUBSTANCE: one places 150 cm³ of wine or beverage into 200 cm³ flask, pH value being higher than 3, and adds 0.1 N of HCl for reduction of the said index to the said value; one performs maintenance at a temperature from 0 to minus 2°C during 24 hours. The resultant residue of tartaric acid salts is collected and subjected to isotopic mass-spectrometer analysis with ¹³C/¹²C stable isotopes relation establishment to identify the summary isotopic characteristics of tartaric acid. One adds 1M of NaOH into the remaining supernatant liquid till pH value is equal to 9, adds 10 cm³ 1M of BaCl₂, heats up to 60°C, cools to 4°C, performs maintenance at the said temperature during 24 hours. The resultant residue is deposited by way of centrifugation, washed with distilled water till pH value is equal to 7 and is dried. Then the residue is subjected to isotopic mass-spectrometer analysis with ¹³C/¹²C stable isotopes occurrence and ratios establishment; the obtained quantitative characteristics and δ¹³C (⁰/₀₀) reference samples characteristics are compared. According to the degree of δ¹³C coincidence or deviation one concludes on organic oxy acids origin.

EFFECT: enhanced accuracy and validity.

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