Innovations & Sustainable Solutions

Aroma and Flavour Testing of Water Bottles

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Aroma and Flavour Testing of Water Bottles
Aroma & Flavour
The testing centre used has a full sensory panel accredited by one of our professional research associates. The panel is trained to evaluate aroma and flavour effects of packaging testing and environment upon food products. Two evaluations are made:
A. Total impact of the flavour or aroma is rated on over a scale of 1 to 3, with 1 being low.
B. The description of the aroma or flavour is through character notes, i.e. of what does it remind the panelist?
Extensive training has heightened the panelists’ awareness and "calibrated" their senses.

Bottle Sourcing
Western Environmental Plastics provided three, one gallon bottles made from: Sample
  • Enviroclear® Copolymer
  • Polyvinyl chloride (PVC)
  • High density polyethylene (HDPE) copolymer
Two additional samples were purchased off the shelf, both containing commercial brand bottled water:
  • One gallon HDPE bottle, probably a homopolymer
  • One quart polyethylene terephthalate (PET) bottle

Analysis Procedure

All five bottles plus a glass jar control were filled with commercial brand bottled water from a five gallon polycarbonate container. After aging for five days at room temperature, portions of the water were placed in beakers, numbered to correspond to the bottle sampled. The numbered beakers were then used in a "blind" aroma and flavour test. The procedure was repeated for samples aged for five days at 45 degrees centigrade.


Laboratory

The Enviroclear® copolymer bottle has the lowest total impact ratings in all tests and results matched the control in three out of four tests. The character notes were the same as the control plus a slight fruity note.


The water aged at 45 degrees was analyzed for organic concentration. The low levels measured on the Enviroclear®, HDPE homopolymer and PVC samples correlate well with panel results. The PET and HDPE copolymer samples tested much higher. Conclusion: The laboratory conclusion is that the Enviroclear® copolymer bottle should be excellent for packaging water.

Results for Aroma and Flavour Testing of Water Bottles


Test Procedure
Five bottles plus a glass jar control were filled with commercial brand bottled water from a five gallon polycarbonate container. After aging for five days, the water was tested for aroma and flavour by a sensory panel.

Bottle Tested

The bottles tested for aroma and flavour were:

Bottle Material Bottle Size
High density polyethylene (HDPE) copolymer 1 Gallon
Enviroclear® copolymer 1 Gallon
Polyvinyl chloride (PVC) 1 Gallon
HDPE homopolymer 1 Gallon
Polyethylene terephthalate (PET) 1 Quart

Results Storage at Room Temp.

For bottles of water stored at room temperature, the aroma and flavour test results were:

Bottle Material Aroma Flavour
Total Impact Character Notes Total Impact Character Notes
HDPE Copolymer 1.0 Musty Gravel Citrus 1.0 Sweet Burnt Poly Throat Catch Plastic
Enviroclear® Copolymer 1.0 Musty Soil/Gravel Fruity Citrus 1.0 Cotton Candy Fruity Throat Catch Plastic
PVC 1.5 Musty Soil/Gravel Sour Old, wet rags 1.5 Plastic Waxy, Musty Throat Catch Sour, Briny
HDPE Homopolymer 1.5 Fruity Sweet Alcohol Musty 1.5 Solvent Sweet, Rye Throat Catch Stale
PET 2.0 Fruity Candy Musty Wax 2.5 Waxy Burnt Poly Throat Catch Bitter
Glass (control) 1.0 Musty Gravel Citrus 1.0 Gravel Plastic

Results for Storage at 45°C

For bottles of water stored at 45 degrees centigrade, the aroma and flavour test results were:

Bottle Material Flavour Measured Organic Concentration
Total Impact Character Notes Total Impact Character Notes
HDPE Copolymer 2.0 Burnt Poly Smokey 2.0 Burnt Poly Plastic Throat Catch 5.3 ng/ml
Enviroclear® Copolymer 1.0 Dusty Pool Water 0.5 Sour Throat Catch 1.0 ng/ml
PVC 1.5 Sour Plastic Pool Water 1.0 Fishy Pool Water Stale 1.5 ng/ml
HDPE Homopolymer 1.0 Dusty Pool Water 1.5 Pool Water 0.6 ng/ml
PET 2.0 Sweet Solventy 2.0 Sweet Solventy Plastic Throat Catch 7.7 ng/ml
Glass (control) 0.5 Clean Water Pool Water 0.5 Gravel Plastic
Observations

The control suggests the following character notes to be common to the water used for the tests, which was commercial brand bottled water from a five gallon polycarbonate container:

Aroma Flavour
Musty Gravel Citrus Pool Water Gravel Plastic Throat Catch

The Enviroclear® copolymer bottle had the least difference from the control in aroma and flavour of the five polymer bottles evaluated.