PROCEDURE
1 . STILL WINES ( 32 )
CAREFULLY DECARBONATE 30 TO 50 ML OF WINE SAMPLE USING A VACUUM PRODUCED BY A WATER-JET PUMP FOR TWO TO THREE MINUTES . IN THE ABSENCE OF A WATER-JET PUMP OR A MECHANICAL PUMP IT IS SUFFICIENT TO SHAKE ENERGETICALLY 30 TO 50 ML OF WINE IN A ONE LITRE BOTTLE FOR FIVE TO 10 SECONDS .
TRANSFER THE WINE TO ANOTHER BOTTLE OF THE SAME CAPACITY AND REPEAT THE SAME OPERATION . THE WINE WILL NOW NOT CONTAIN MORE CARBON DIOXIDE THAN 2 OR 3 ML/L .
POUR A FEW MILLILITRES OF THE DECARBONATED WINE INTO THE LABORATORY BOTTLE . SHAKE ( FOR A SHORT TIME ) TO DISTRIBUTE THE WINE OVER ALL THE INTERNAL WALLS OF THE BOTTLE ; DRAIN QUICKLY , STOPPER THE BOTTLE AND PLACE IT ON THE WATERBATH . AFTER ONE TO TWO MINUTES THE WATER LEVEL IN THE PRESSURE GAUGE WILL HAVE BECOME STEADY .
OPEN THE TAP ON THE PRESSURE GAUGE , INTRODUCE INTO THE CENTRAL TUBE APPROXIMATELY 20 ML OF DECARBONATED WINE , AND THEN 50 ML OF WINE TO BE ANALYZED BY DIPPING THE PIPETTE TO THE BOTTOM OF THE TUBE THUS AVOIDING RAPID DELIVERY . RESTOPPER , CLOSE THE TAP ON THE PRESSURE GAUGE AND SHAKE VIGOROUSLY FOR FIVE TO 10 SECONDS . STAND IN A WATERBATH FOR ONE OR TWO MINUTES AND THEN SHAKE THE BOTTLE FOR TWO SECONDS BEFORE PUTTING IT BACK ON THE WATERBATH . READ THE EXCESS PRESSURE H AS SOON AS THE WATER LEVEL IN THE PRESSURE GAUGE HAS BECOME STEADY . NOTE THE TEMPERATURE T* C OF THE BATH .
CALCULATION : THE HEIGHT OF WATER IN THE PRESSURE GAUGE IN MILLIMETRES MUST BE MULTIPLIED BY THE FACTOR F TO GIVE THE QUANTITY OF CARBON DIOXIDE IN MILLILITRES OF THIS GAS PER LITRE OF WINE .
THIS FACTOR F VARIES BETWEEN 1.7 AND 1.9 ACCORDING TO THE TEMPERATURE AND THE CAPACITY OF THE LABORATORY BOTTLE . IT IS GIVEN IN COLUMN 2 OF TABLE I .
TO EXPRESS THE CONTENT IN MILLIGRAMS PER LITRE OF WINE , MULTIPLY THIS RESULT BY 1.977 .
2 . SPARKLING AND SEMI-SPARKLING WINES , BEER , ETC .
BEFORE COMMENCING , MARK ON THE NECK OF THE BOTTLE OF SPARKLING WINE THE LEVEL OF WINE IN THE BOTTLE . COOL THE FULL AND STOPPERED BOTTLE TO - 4* C . IMMEDIATELY AFTER UNSTOPPERING WITHDRAW 30 ML ( 33 ) OF WINE ( ASSUME THE BOTTLE TO CONTAIN APPROXIMATELY 800 ML OF WINE ) . IMMEDIATELY INTRODUCE 30 ML ( 33 ) OF SODIUM HYDROXIDE SOLUTION 50 % . RESTOPPER ENSURING THAT THE AIR POCKET IS NOT GREATER THAN 3 ML . IMMEDIATELY SHAKE AND THEN BRING THE BOTTLE TO ROOM TEMPERATURE .
INTRODUCE 1 ML OF SODIUM HYDROXIDE SOLUTION 50 % AND 10 ML OF WINE WHICH HAS BEEN MADE ALKALINE ( CASE OF SPARKLING WINE ) OR 20 ML OF ALKALIZED WINE ( CASE OF SEMI-SPARKLING WINE ) INTO