Open Bottle Storage: Vacuum Seal
750 ml bottle top vacuum sealed
750 ml bottle and "Foodsaver Bag" before being vacuum sealed
750 ml bottle and "Foodsaver Bag" after being vacuum sealed

Open Bottle Storage: Vacuum Seal

We wanted to see if there was any additional value in creating a perfectly airtight seal. Many people in the whisky would use a paraffin to create an additional seal by using a product called "Parafilm." Paraffin wax is great because it does not get eaten away by alcohol. However, paraffin wax still allows for the passage of gasses which means it is only functional as a liquid barrier. This is why we did not use paraffin wax for any tests. Instead we used vacuum sealing to create an airtight seal.

The method of vacuum sealing we used was to create a seal, not necessarily to remove air from within the bottle. (Although this might occur during the sealing process.) To create the seal, we first took the bottle and sealed with its regular cap. Then placed the entire bottle into a "FoodSaver Bag" which is vacuum sealed with the "FoodSaver FM2000." All bottles were stored upright in a dark temperature controlled environment to eliminate other variables.

We created three sets of vacuumed vs not vacuum sealed specimens to test.

  • Set One: five 4 oz amber glass bottles filled to the top.
    • Three were vacuum sealed.
    • Two were not vacuum sealed.
  • Set Two: four 750 ml bottles filled with 150 ml of whisky and sprayed with 15 seconds of "Private Preserve."
    • Two were vacuum sealed.
    • Two were not vacuum sealed.
  • Set Three: four 750 ml bottles filled with 150 ml of whisky.
    • Two were vacuum sealed.
    • Two were not vacuum sealed.
All were stored upright in a dark temperature controlled environment to keep cool and eliminate other variables.


A Year Later

NOTE: When we speak about the differences in taste or score, it is the difference between a specimen and the control, and another specimen and the control. Not the direct difference between the two specimens.

The value of vacuum sealing is uncertain. In fact, it could actually be harmful to whisky. The first two sets showed vacuum sealing yielded a slight benefit of 0.44 and 0.17 points. However, the last set yielded a negative effect of -0.92 points. This left us with vacuum sealing hurting the quality of the whisky by an average of -0.10. While this is well under the standard deviation of 0.39 points, the range of variation in the raw data is large enough to void the standard deviation. Because of this we do not suggest vacuum sealing.

The average scores of each set of specimens. (Lower is better.)
Specimen Description Total Average Nose Average Palate Average Finish Average
Vacuum sealed, 4 oz decanted bottle, filled to the top, cool dark place 1.56 0.94 2 1.75
4 oz decanted bottle, filled to the top, cool dark place 2 1.25 2.38 2.38
Vacuum sealed, Private Preserve, 750ml bottle, 150ml fill, cool dark place 3.5 3 3.75 3.75
Private Preserve, 750ml bottle, 150ml fill, cool dark place 3.67 3.75 3.75 3.5
Vacuum sealed, 750ml bottle, 150ml fill, cool dark place 2.88 2.5 3.38 2.75
750ml bottle, 150ml fill, cool dark place 1.96 2 2.13 1.75