The taste of water and perception of chlorine

A positive result for the project "Pleasant to drink tap water"

August 19, 2009 Launched in September 2006, the project "Pleasant to drink tap water" that was developed with Vitagora, will soon come to an end. 

Within this project, two post-doctoral theses have been carried out. The first, which will be finished at the end of August, studies the intrinsic taste of water and consumer preferences. The second, to be finished next autumn, is interested in the perception of the taste of chlorine be consumers. Already or soon to be published, several results obtained by these two theses will lead to technological development within Lyonnaise des Eaux. "We will be able to improve our existing processes, with the aim of taking into account in particular the problem of taste," declares Virginie Rouche, project engineer and manager for Lyonnaise des Eaux.

The research carried out for the thesis on the intrinsic taste of water has allowed researchers to observe that the determinants of the taste of water are always the same, wherever the water is from: mineral water or from a tap. "The main determinant is the mineral composition, what we call dry residue at 180° C, which corresponds to the total mineral content in one litre of water," she explains, adding that certain minerals have a greater influence that others. 

It is now possible to categorise waters in three classes according to their taste. First, there are bitter or metallic waters that carry little minerals (less than 200 mg/L). Next tere are the neutral waters that have a moderate mineral contect (around 300 mg/L). The waters that seem salty and give the consumer a sense of astringence or a dry mouth sensation contain a greater quantity of minerals (over 800 mg/L). 

 The mineral content depends on the type of sub-soil that the water has travelled through. "Our research has also showed that the average preference of consumers is for neutral waters, but depends on a number of complex factors."

From the research carried out for the thesis on the consumer perception of chlorin, it has emerged that chlorine added to water to guarantee its safety has no taste, but a smell. "More than half of French people perceive chorine in water where it is added in concentrations defined by regulations that drinking water producers must adhere to," adds Virginie Roche  

This research has shown that the threshold of populations used to drinking tap water, and thus faced with the odour of chlorine, is no different from that of populations used to drinking bottled water. Finally, it has been shown that this is above all the mental perception that consumers have of a product that  is the greatest deciding factor in their decision to drink tap water or not.

Contact
Virginie Roche
Email : virginie.roche@lyonnaise-des-eaux.fr

Source : Agence JFD and Co