Does Temperature Affect Vegetable Glycerine and Propylene Glycol?

Yes. Temperature can have a noticeable effect on both Vegetable Glycerine and Propylene Glycol.

The biggest change you are likely to notice is viscosity. In simple terms this means how thick or thin a liquid is and how easily it flows.

When temperatures drop both VG and PG become more viscous. When temperatures rise they become thinner and flow more easily.

The effect is particularly noticeable with Vegetable Glycerine because VG is already considerably thicker than Propylene Glycol at normal room temperature.

So why does this happen and does it matter when using VG and PG?

How Does Temperature Affect Vegetable Glycerine?

Vegetable Glycerine is naturally a thick and syrup like liquid.

As the temperature drops VG becomes even thicker. This means it may pour more slowly and take longer to move through measuring equipment.

As Vegetable Glycerine becomes warmer its viscosity decreases which allows it to flow more freely.

This does not necessarily mean there is anything wrong with your VG.

A bottle stored somewhere cold may simply behave differently from the same product stored at a normal room temperature.

Can Vegetable Glycerine Become Very Thick in Cold Weather?

Yes.

Cold temperatures can make Vegetable Glycerine noticeably thicker.

You might notice:

• Slower pouring

• More VG remaining around the sides of a container

• Longer filling times

• More difficulty using syringes or other measuring equipment

• Bubbles taking longer to rise through the liquid

At sufficiently low temperatures glycerine can also begin to crystallise.

If VG has simply become thicker because it is cold allowing the sealed container to gradually return to normal room temperature should help restore its usual consistency.

How Does Temperature Affect Propylene Glycol?

Propylene Glycol is much thinner than Vegetable Glycerine but its viscosity is still affected by temperature.

Cold PG becomes thicker while warmer PG becomes thinner and flows more easily.

The difference may be less obvious than it is with VG because Propylene Glycol naturally has a much thinner consistency.

Even so temperature can still matter when PG is being measured or used within a precise formulation.

Which Is More Affected by Cold Temperatures: VG or PG?

Both liquids are affected but the change is usually much easier to notice with Vegetable Glycerine.

VG starts with a much thicker consistency than PG.

When it becomes colder that viscosity can increase considerably which makes pouring and measuring more difficult.

Propylene Glycol generally remains much more fluid at temperatures where Vegetable Glycerine may already feel noticeably thicker.

Why Does Temperature Matter When Measuring VG and PG?

Temperature can matter when accurate measurements are important.

A cold bottle of VG may pour much more slowly than expected. Thick liquid can also remain attached to measuring equipment or the inside of a container.

This can make working with precise quantities more difficult if you are measuring quickly.

Temperature can also cause small changes in density and volume.

For consistent results it is therefore useful to measure ingredients under similar conditions each time especially when working with repeat formulations or commercial production.

If accurate measurement is important you can also read our guide on VG vs PG: Weight, Density and How to Measure Them.

Does Temperature Change the Quality of VG or PG?

A temporary change in viscosity does not automatically mean the product has deteriorated.

If your VG appears thicker during colder weather it may simply be a result of the temperature.

The same applies to PG although the change may be less noticeable.

However VG and PG should still be stored correctly.

Long term exposure to excessive heat and direct sunlight and contamination should be avoided. Keep containers securely closed when they are not being used.

For more information see our guide on How to Store Vegetable Glycerine and Propylene Glycol.

Should You Warm Vegetable Glycerine Before Using It?

If Vegetable Glycerine has become particularly thick after being stored somewhere cold the safest and simplest option is normally to allow the sealed bottle to return naturally to room temperature before measuring it.

Avoid exposing VG or PG to unnecessary high temperatures.

For most everyday applications there is no need to actively heat either liquid.

Giving the product time to reach a comfortable room temperature can make pouring and measuring much easier.

Does Temperature Affect VG and PG Mixtures?

Yes.

A mixture containing Vegetable Glycerine and Propylene Glycol can also become thicker or thinner depending on temperature.

The amount of VG within the mixture will have a significant influence on its overall viscosity.

A mixture containing a higher proportion of VG will generally be thicker than one containing more PG.

Cold conditions can make this difference even more noticeable.

Does Temperature Affect Storage?

Temperature is an important consideration when storing both VG and PG.

For general storage keep bottles:

• In a cool and dry location

• Away from direct sunlight

• Away from strong heat sources

• Securely sealed

• Protected from contamination

Try to avoid unnecessary temperature extremes.

Consistent storage conditions help keep the product easier to handle and help protect its quality over time.

Vegetable Glycerine Temperature FAQs

Does Vegetable Glycerine get thicker when cold?

Yes. Vegetable Glycerine becomes more viscous as its temperature decreases. This means it becomes thicker and pours more slowly.

Does Vegetable Glycerine get thinner when warm?

Yes. As Vegetable Glycerine becomes warmer its viscosity decreases and it flows more easily.

Does Propylene Glycol get thicker when cold?

Yes. Temperature also affects the viscosity of Propylene Glycol although the change may be less noticeable because PG is naturally much thinner than VG.

Can Vegetable Glycerine freeze?

Glycerine can crystallise under sufficiently cold conditions. If your VG has been exposed to low temperatures allow it to gradually return to room temperature before assessing its condition.

Why is my Vegetable Glycerine suddenly very thick?

Temperature is one possible explanation. If the bottle has been stored somewhere colder than usual VG can become noticeably thicker.

Should VG and PG be the same temperature when measuring?

For repeat formulations it is good practice to work under similar conditions each time. This helps improve consistency when measuring and handling the liquids.

Temperature Makes a Difference

Temperature can have a noticeable impact on how Vegetable Glycerine and Propylene Glycol behave.

Cold temperatures increase viscosity while warmer temperatures reduce it.

The effect is particularly noticeable with Vegetable Glycerine because VG is naturally much thicker than PG.

If your VG seems unusually thick during colder weather there may be nothing wrong with it. Allowing the sealed container to return naturally to room temperature will often make it easier to pour and measure.

For the best results store VG and PG correctly and try to use them under consistent conditions when accurate measurements are required.

Explore the VGPG Online range of Vegetable Glycerine and Propylene Glycol for home and business and commercial applications across the UK.