Water filtration process increases sugar levels in drinks
Increasing the pH level of water could help tackle health problems caused by high sugar content in drinks.
Scientists at De Montfort University Leicester (DMU) have been working with University of Sheffield, Innovate UK and WET Group Ltd to find a way to create drinks that do not need sugar or additives.
To do this, they looked at why sugar is added to drinks in the first place and found that the water purification process known as Reverse Osmosis (RO) can reduce the liquid’s pH level to values of 6.1 or lower – compared to water’s neutral pH level of 7.
RO removes dissolved salts (ions) and unwanted bacteria from drinking water by pushing it under pressure through a semi-permeable, thin membrane with tiny pores that restrict larger molecules and impurities from getting through.
However, researchers found that this process causes the liquid to become more acidic through the uptake of atmospheric carbon dioxide, leaving a salty, bitter taste. As a result, sugar is added to drinks to cover up this adverse flavour.
“Our study shows that in order to reduce the amount of sugar in drinks, we need to look at the way we treat the water beforehand,” said Professor Martin Grootveld, professor of Bio-analytical Chemistry and Chemical Pathology at DMU.
“Sugar is being used to disguise the acidity in drinks, rather than improve the flavour, and actually adding sugar causes the pH value of water to decrease even further – we found some drinks had a highly acidic pH level of 2.5.”
Companies now have the opportunity to create new filtration innovations that can maintain a higher pH value so sugar does not need to be added.
“With a rapidly growing global population, there is an increasing need for innovation if we are to meet the demand for more efficiently produced, healthier and traceable food,” added Kathryn Miller, Innovation Lead – Food and Nutrition, Innovate UK.