Top Tips on avoiding Glass Bloom

Clouds without silver linings.

The appearance of a glass will have an effect on your customers. If they perceive the glass is dirty, then a large number of people will leave your establishment without a word and simply never return.

If a glass is not treated correctly, then overtime it can develop what is known as bloom.

Bloom takes the form of a milky white mark or in serious cases can look similar to frost lines on a window pane in winter. For most types of drinking glass this is only an aesthetic issue and will not affect the quality of the beverage but to a discerning customer this can ruin their drinking experience.
Blooms are typically caused by a build-up of Sodium Carbonate (Soda Ash) or Calcium Carbonate (Limescale) either on the surface or within micro-fractures of the glass. If you wet the surface of a glass that has bloom it will often look normal until it begins to dry and the bloom reappears.

Tips on treating bloom

These deposits can be created in the following ways:

  • Using a dishwash detergent to clean glassware – Dishwash detergents contain a high amount of sodium hydroxide (Caustic Soda) which can scratch, etch and damage glassware causing micro-fractures that can allow bloom to form. Always ensure you are using a glasswashing machine with a specific glasswash detergent.
  • Too much salt in the glasswashing machine – An excess of salt from a faulty water softener can also etch and scratch the glassware.
  • Using hard water with no water softener – If you are not using a glasswashing detergent that is specially formulated for hard water areas then limescale spots will build up on the glass in the form of small white spots or marks, if left untreated this will eventually turn into bloom.
  • Using too much detergent or water temperature that is too high – Using more than the recommended dosage rate of detergent not only wastes money but can cause damage to glassware. Wash and rinse temperatures that are too high (Above 55 degrees for washing and 65 degrees for rinsing) can cause thermal shock to glasses. Get your service engineer to check your wash/rinse temperatures and dosage levels are correct at each service interval.
  • Stacking glasses inside each other – We know it’s easier when collecting glasses to stack one inside the other but this causes surface scratches that can allow bloom to form.

Minor blooms on the surface of a glass can be removed by using a suitable Sodium/Potassium Hydroxide (Caustic Soda/Potash) free Glass Renovator, but if the glass has become damaged and has an ingrained bloom then these are very difficult to remove and the glass will in most cases need replacing.

It is important to know that even if a bloom can’t be seen there can still be very minor traces of mineral deposits building up on the surface of the glass. Using the right cleaning products along with taking good care of your glasswasher can do wonders for the lifespan of your glassware.

Ask the experts about the best methods and products to stop bloom on your glassware.

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