| Milking staff should look for clots, strings, wateriness or discolouration of milk. |
| Pollutants in the atmosphere and the attentions of birds and humans cause discolouration, encrustation and corrosion. |
| Herbert B. Berkeley recommended the use of sulphite of soda with pyrogallic acid to prevent discolouration of film. |
| Tooth decay, fillings and tartar build-up can also all contribute to discolouration. |
| For instance, you may experience dryness or even mild discolouration in patches. |
| When the job is finished, you should not place items such as mats on the floor for several weeks, as they will cause discolouration. |
