Scientists have developed a breakthrough method to efficiently produce tagatose, a rare natural sugar that tastes almost like regular sugar but contains significantly fewer calories and does not cause sharp spikes in insulin or blood glucose levels. The discovery could pave the way for a healthier alternative to both table sugar and artificial sweeteners.
Tagatose is around 92 per cent as sweet as sucrose but delivers only one-third of the calories, making it an attractive option for people with diabetes, insulin resistance, or those looking to reduce sugar intake without sacrificing taste.
The research was carried out by scientists at Tufts University, in collaboration with biotechnology companies Manus Bio (United States) and Kcat Enzymatic (India). The findings were published in the journal Cell Reports Physical Science.
Why Tagatose Has Been Hard to Use Commercially
Although tagatose occurs naturally in small quantities in certain fruits and dairy products, its commercial use has been limited due to high production costs and inefficient manufacturing processes. Existing methods require complex chemical steps and deliver low yields, making large-scale production impractical.
To overcome these challenges, researchers turned to biotechnology.
Bacteria Turned into Sugar-Producing Factories
The team genetically engineered Escherichia coli (E. coli) bacteria to act as miniature production units. By introducing a newly discovered enzyme from slime mold — called galactose-1-phosphate-selective phosphatase — the scientists enabled the bacteria to efficiently convert glucose into tagatose.
This innovative process achieved production yields of up to 95 per cent, dramatically outperforming existing methods.
“There are established processes to produce tagatose, but they are inefficient and expensive,” said Nik Nair, a biological engineer at Tufts University.
“We developed a way to produce tagatose by engineering the bacteria Escherichia coli to work as tiny factories, loaded with the right enzymes to process abundant amounts of glucose into tagatose.”
Health Benefits Beyond Lower Calories
In addition to its low-calorie and low-glycaemic properties, tagatose offers other health advantages. Researchers say it is tooth-friendly, as it does not promote the growth of harmful oral bacteria, unlike conventional sugar. It may even help limit bacterial activity in the mouth.
Another advantage is its heat stability. Unlike many artificial sweeteners, tagatose can withstand baking and cooking temperatures, making it suitable for a wide range of food products.
A Growing Market for Rare Sugars
While the new method still requires further optimisation before full commercial rollout, scientists believe it could significantly expand the availability of tagatose and other rare sugars.
According to industry estimates, the global tagatose market is expected to reach $250 million by 2032, driven by rising demand for healthier sweeteners amid growing concerns over diabetes, obesity and metabolic disorders.
If successfully scaled, the breakthrough could mark a major shift in how sugar alternatives are produced — offering consumers a natural, tasty and health-conscious option without the drawbacks of traditional sugar.