Tagatose in toast bread changes texture, flavour and glycemic index
What it found
In lab tests, replacing sucrose with tagatose in toast bread lowered the glycemic index and increased flavour compounds, but made the bread denser and more acidic.
What they found
Water holding and volume
Dough made with tagatose held more water, but the finished toast had a smaller specific volume, dropping from 4.74 to 3.01 mL/g.
Acidity
Toast acidity rose from 1.92 to 2.69°T as tagatose increased.
Flavour compounds
Adding tagatose significantly increased flavour substances, especially alcohols, in the toast.
Glycemic index
The glycemic index of the toast fell from 94.39 to 67.96 when tagatose was used.
Overall effect
Using 12% or more tagatose greatly lowered the glycemic index and boosted flavour, but made the bread denser and more acidic.
What the authors conclude
“Overall, the addition of 12% or more tagatose will significantly reduce the GI of toasted bread and enrich the flavor, but it will lead to a decrease in specific volume and an increase in acidity.”
Also in their conclusions
- They say that adding 12% or more tagatose will significantly reduce the GI of toasted bread and enrich the flavor, but it will lead to a decrease in specific volume and an increase in acidity.
- They describe tagatose as a promising alternative sweetener with low calorie.
How it was done
With obesity and diabetes rising worldwide, the authors wanted to find ways to cut sugar without losing food quality. Tagatose has not been widely used in toast bread because it is expensive.
They made five types of toast bread with different amounts of tagatose (0%, 4%, 8%, 12%, and 16%) instead of sucrose, keeping sweetness similar. They then tested the bread's structure, texture, nutrition, flavour, and how it broke down in lab digestion tests.
What it can’t tell you
- We summarised it from the abstract only.
- This study was done in a lab, not in people, so it cannot show how tagatose toast affects blood sugar or health in real life.
- The digestion tests were done outside the body, so they cannot show what happens when people eat the bread.
Who paid
- Funding
- Funded by Key Research and Development Project of Henan Province; Henan Provincial Key Science & Technology Special Project; Key Scientific and Technological Research Projects of Henan Province; Cultivation Programme for Young Backbone Teachers in Henan University of Technology (from the PubMed record).
- Authors work at
- Henan University of Technology, China; Food Laboratory of Zhongyuan, China; Zhengzhou Engineering Research Center of Bioactive Peptides, China
The paper
- Title
- Impact of Tagatose on Physicochemical, Nutritional, and In Vitro Digestive Properties of Toast Bread
- Type
- Study
- Summarised from
- Abstract only
- Cite
- Wang JQ, Liu XG, Ding ZR, et al (2025). Impact of Tagatose on Physicochemical, Nutritional, and In Vitro Digestive Properties of Toast Bread. Journal of food science. doi:10.1111/1750-3841.70213PubMed 40344578DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error