Beer

Procedures to determine the net volume of prepackaged beer products.

Labelling and testing requirement

All packaged foods must be marked and sold with a stated net quantity on the package. All packaging must be excluded from the quantity statement.

For more information see:

The following procedures have been developed to help Trading Standards Officers, packers and importers determine whether the stated net volume on packaged beer products is correct.

Procedure 1 – direct volumetric measurement

Required equipment

You’ll need the following equipment to complete the testing procedure:

  • Calibrated volumetric cylinder.
  • Timer or stopwatch.
  • Antifoaming agent.
  • Dropper or pipette.
  • Can / tin opener.
  • Solid level surface, workbench or table.
  • White background (paper or wall).
  • Calculator.

Step 1

  • Record the product name, batch number / ID and stated net volume of product.

Step 2

  • Wet the volumetric cylinder by filling it to at least the stated net volume with a sample of the beer to be tested. Empty the cylinder and once the flow slows to drips, allow draining for 30 seconds, using the stopwatch to time this. Place the cylinder upright on a flat surface.

Photo of step 2

Step 3

  • Use a dropper or pipette draw up 0.5 mL of the antifoaming agent.

Photo of step 3

Step 4

  • Insert the tip of the dropper or pipette inside the rim of the volumetric cylinder.

Step 5

  • Hold the volumetric cylinder at approximately 15 degrees and dispense the antifoaming agent slowly into the volumetric cylinder.

Photo of step 5

Step 6

  • Select a prepackaged beer product:
    • Bottled beer: open the product and empty its entire contents into the volumetric cylinder, near to the spot where the antifoaming agent was added, while holding the volumetric cylinder at approximately 15 degrees.
    • Canned beer: open the ring pull slightly to allow the CO2 to escape, then use a can / tin opener to remove the top of the can. Empty the entire contents into the volumetric cylinder, near to the spot where the antifoaming agent was added, while holding the volumetric cylinder at approximately 15 degrees. 

Photo of step 6

Step 7

  • Once the flow slows to drips from the product, allow draining for 30 seconds using the stopwatch to time this.

Photo of step 7

Step 8

  • Place the volumetric cylinder on the solid level surface, workbench or table in front of the white background (paper or wall) and take the volume reading on the graduated scale.

Photo of step 8

Note: Reading a graduated cylinder  It is important to ensure you are taking an accurate reading when using a graduated cylinder. Ensure you are eye level with the liquid and you are reading from the bottom of the meniscus.

Diagram showing how to judge the correct level in a graduated cylinder

Step 9

  • Calculate the actual net volume by subtracting 0.5 mL from the volume reading taken in Step 8 to account for the antifoaming agent added in Step 5.

Step 10

  • Calculate the error by subtracting the actual net volume recorded in Step 9 from the stated net volume recorded in Step 1.

Step 11

  • Repeat Step 1 to Step 10 for each sample selected.

Example of recording volume checks for packers

Product NameBatch Number / IDStated Net Volume (mL)Anti-foaming Agent Added (mL)Actual Net Volume (mL)Error (mL)
Lager  20191109  440  0.5  445  + 4.5
Porter  20191108  750  0.5  742  - 8.5

Note: This is a destructive test method, which means that each individual sample tested is destroyed in order to determine its volume.

Procedure 2 – using density to determine volume

Required equipment

You’ll need the following equipment to complete the testing procedure:

  • Electronic density meter.
  • Conical filter paper.
  • Weighing instrument.
  • Solid level surface, workbench or table.
  • Beaker/vessel.
  • Funnel.
  • Calculator.

Step 1

  • Record the product name, batch number / ID and stated net volume of the packaged beer.

Step 2

  • Select a packaged beer, zero the weighing instrument, place the packaged beer on the weighing pan and record the weight.

Step 3

  • Fold the conical filter paper into a cone shape.

Step 4

  • Place the filter paper inside the top of an appropriate sized funnel.

Step 5

  • Place the funnel into a suitable sized beaker / vessel.

Step 6

  • Open the packaged beer and pour the liquid into the conical filter paper. Ensure that any removable bottle cap, ring pull or lid is retained.

Photo of step 6

Step 7

  • Allow the liquid to pass through the filter paper until at least 5 mL of degassed beer is collected in the beaker / vessel. 

Photo of step 7

Step 8

  • Check if filtered liquid contains any visible gas bubbles. If so, pass the liquid through the filter paper again. Repeat this step until the liquid is fully degassed.

Step 9

  • Using the electronic density meter, take the density measurement of the degassed liquid. 

Photo of step 9

Step 10

  • Empty the packaged beer of all liquid, zero the weighing instrument, place empty vessel (including any cap, ring pull or lid previously removed) on the weighing pan and record the weight.

Step 11

  • Calculate the actual net volume by dividing the weight of the contents by the density figure. 

Example calculations

Weight of a full package:  400 g
Weight of empty packaging: - 75 g
Weight of the beer in the package = 325 g

Weight of the beer in the package: 325 g
Density of the beer: ÷ 1.011 g/mL
Actual net volume = 321.5 mL

Actual net volume: 321.5 mL
Stated net volume: - 330 mL
Error = - 8.5 mL

Example of recording volume checks for packers

Product NameBatch Number / IDStated Net Volume (mL)Weight of Full Package (g)Weight of Empty Packaging (g)Weight of Beer in Package (g)Density of Beer (g/mL)Actual Net VolumeError (mL)
Stout  20181111  330  400  75 325 1.011 321.5 - 8.5
IPA  20181110  650  750  80 670 1.014 660.7 + 10.7

Note: This test method can be used to determine the volume of multiple packages from the same batch without destruction of each sample, assuming that the density of the beer and the packaging weight remains constant.

Required equipment – specification and maintenance

All weighing and measuring equipment used by beer manufacturers / packers to complete quantity checks should be calibrated at regular intervals, or when the equipment may have been damaged. Check equipment regularly to ensure it remains accurate and the recommended manufacturer service regimes are followed.

Below is a list of the equipment that you may use as part of a quantity control system and the recommended specifications.

  1. Graduated cylinder:
    1. Total capacity should be greater than the stated volume of the package.
    2. Measurement increments should be no greater than either 1% of its capacity or 5 mL, whichever is less.
  2. Antifoaming agent:
    1.  1-Octanol, n-Octanol, Capryl alcohol, Octyl alcohol, Hexanol or equivalent.
  3. Electronic density meter:
    1. Accurate to 0.001 g/mL.
    2. Calibrate the meter every time before use, or at least once at the beginning of each day by using distilled water or other accurate reference density liquid, i.e. 1.000 g/mL at the intended sample measurement temperature.
    3. Clean and dry the U-tube of the meter at the end of each working day. Follow this three-step process:
      1. A solvent to dissolve sample residues (eg distilled water or enzymatic lab cleaner).
      2. An alcohol to remove sample residues.
      3. Air via syringe to dry U-tube.
    4. When measuring a sample that is very different from the previous sample, flush the U-tube with distilled water.  For example, when testing two distinct types of beer.
    5. Follow the density meter manufacturer’s instructions when maintaining the equipment and when taking density readings.
  4. Conical filter paper:
    1. Filter paper with a pore size of 11 micrometres and a filtration speed of 150 seconds per 100 mL is suitable for degassing the beer.
  5. Weighing instrument:
    1. An instrument that weighs in increments of 0.1 gram for beers between 250 mL and 1 L.
    2. It is recommended that the instrument is verified (bearing a Mark of Verification) and has a current Certificate of Accuracy, both of which can be issued by an Accredited person.

Maintaining a valid certificate may provide you with a defence if a breach of the Weights and Measures Act 1987 is discovered by Trading Standards.

Equipment used for weighing and measuring has more information.