When you download the glass jars, you can change and modify them in whatever way you want.
The high-resolution PSD files come with altogether 94 individual PSD layers so you have the greatest flexibility to adapt them to your personal needs!
For example, have you noticed that glass panes often have a color tint?
Depending on where the glass stands and what kind of light is reflecting in it, the glass takes on a blue, green, purplish, etc. tint.
You can recreate that effect by adding a Hue & Saturation Adjustment Layer. Add this adjustment layer above any of the glass layers that you want to apply the effect to.
As you have 94 layers available, you can precisely select which layer or layers you want to give a color tint.
Create a clipping mask for the Hue & Saturation Adjustment Layer and check the Colorize box. Move the Color and Opacity sliders to adjust type and intensity of the color effect.