Engineered Bacteria Convert Glucose into Tagatose—A Low‑Calorie Sugar That Tastes Like Table Sugar

Breaking: tufts Researchers Unveil Efficient Biosynthesis Of Rare Sugar Tagatose

In a breakthrough that could redefine how the world sweetens foods, scientists from tufts University report a new biosynthetic method to produce tagatose, a rare sugar that tastes like table sugar but carries fewer calories and health risks.

the research suggests tagatose, already recognized as safe for use in foods, could become a practical option for reducing sugar in the global diet while preserving flavor and baking performance.

The study describes turning common glucose into tagatose through a engineered bacterial system, a process that promises higher efficiency and lower production costs than traditional methods.

What Is Tagatose And Why It Matters

Tagatose occurs naturally in very small amounts, primarily during the heating or enzymatic breakdown of lactose in dairy products such as yogurt, cheese, and kefir. It is also present in tiny traces in certain fruits, but its natural supply is far too scarce for wide use.

As of this scarcity, tagatose is typically produced through manufacturing processes rather than extracted directly from foods.It delivers about 92% of the sweetness of table sugar while containing roughly 60% fewer calories, making it an appealing option for reducing caloric intake.

Health-wise, tagatose is absorbed only partially in the small intestine, with much of it fermented by gut bacteria in the colon. This results in a smaller effect on blood glucose and insulin levels compared with conventional sugar. Early clinical observations indicate minimal rises in glucose and insulin after consumption.

In addition to metabolic effects, tagatose may support oral health by limiting the growth of certain cavity-causing bacteria.Some studies also hint at probiotic benefits for both mouth and gut ecosystems.

How The New Biosynthesis Works

The team’s approach relies on genetically engineered bacteria that act as tiny factories, equipped with enzymes to convert abundant glucose into tagatose. A key innovation is the introduction of a slime-mold enzyme that enables the generation of galactose directly from glucose.An additional enzyme then converts galactose into tagatose, enabling highly efficient production.

In laboratory tests, this method achieved tagatose yields up to 95%, a notable betterment over conventional manufacturing techniques, which typically achieve 40% to 77% yields. The higher efficiency translates into lower production costs and greater feasibility for large-scale use.

Engineered bacteria in the study carry a galactose-1-phosphate-selective phosphatase enzyme, along with arabinose isomerase, to complete the conversion process. This configuration allows tagatose to be produced directly from glucose fed to the bacteria.

why This Revelation Could Reshape Sweeteners

Experts say the central advance—splicing a slime-mold Gal1P enzyme into production bacteria—reverses a natural pathway, enabling the generation of galactose from glucose fed into the system. This could unlock efficient production of other rare sugars, potentially transforming how sweeteners are manufactured and used in foods.

Tagatose’s blend of near-sugar sweetness,reduced calories,and favorable metabolic properties positions it as a practical option for reformulating foods and beverages. It also reinforces the role of bioengineering in creating safer, more cost-effective ingredients without sacrificing taste or cooking performance.

Key Facts At A Glance

Aspect	Details
Natural occurrence	Trace amounts in dairy; also found in small amounts in some fruits; typically under 0.2% of sugars in natural sources
Primary source for use	Manufacturing production due to scarcity in nature
Sweetness vs sugar	About 92% of sucrose sweetness
Calorie count	Approximately 60% fewer calories than sugar
Safety status	FDA generally recognized as safe (GRAS)
Metabolic impact	Partial absorption; lower blood glucose and insulin responses
Oral health	May inhibit cavity-causing bacteria; potential probiotic effects
Cooking properties	Browns like sugar; provides bulk and mouthfeel similar to sucrose
Production yields	Yields up to 95% with the engineered system; typical methods 40–77%
Key enzymes	Galactose-1-phosphate-selective phosphatase (Gal1P); arabinose isomerase
Host organism	Genetically modified Escherichia coli

Context And outlook

Experts see this as a turning point for rare sugars, with the potential to expand the palette of safe, low-calorie sweeteners available to food makers. If scaled, tagatose could support reformulation efforts across products from beverages to baked goods, preserving taste while reducing sugar-related health risks.

For curious readers,additional context on regulatory status and safety standards for sugar substitutes can be found on official health agency resources.

What foods would you like to see tagatose used in? Do you think this breakthrough will accelerate the mainstream adoption of safer sweeteners?

Stay Informed, Stay Curious

As researchers refine the process and scale production, tagatose could become a larger part of the conversation about healthier, tastier diets. The ongoing evolution of bio-based sweeteners invites readers to watch how breakthroughs translate into everyday products.

Share this breaking update and tell us your thoughts in the comments below. Do you welcome a future with safer, sugar-like sweeteners in more foods?

Disclaimer: The information presented here is intended for general readers and should not be taken as medical or dietary advice. Consult health professionals for guidance related to sugar intake and metabolic health.

External references: FDA GRAS Substances; Tagatose – PubChem

Return to top for more updates as the research progresses.

How does metabolic engineering enable engineered bacteria to convert glucose into tagatose?

.## How Engineered Bacteria Turn Glucose into tagatose

Key process: Metabolic engineering of Escherichia coli and Corynebacterium strains enables a two‑step enzymatic pathway that transforms inexpensive glucose into tagatose, a low‑calorie sweetener that mimics the taste profile of sucrose.

1. The Science Behind the Conversion

Step	Enzyme (native or engineered)	Reaction
1️⃣	Glucose isomerase (mutated for higher specificity)	Glucose → D‑galactose
2️⃣	L‑arabinose isomerase (optimized for thermostability)	D‑galactose → Tagatose

Why it works: Traditional chemical synthesis of tagatose requires high temperature, strong acids, and costly purification. The engineered bacterial route runs at 30‑37 °C, uses water‑based media, and yields >90 % purity after simple downstream processing.

2. Advantages Over Conventional sweeteners

• caloric reduction: Tagatose provides ~1.5 kcal g⁻¹ versus 4 kcal g⁻¹ for table sugar.
• Glycemic impact: Low glycemic index (GI ≈ 3) makes it suitable for diabetics.
• Prebiotic effect: partial fermentation in the colon supports beneficial gut bacteria.
• Stability: Retains sweetness after heating, ideal for baking and beverage applications.

3. Real‑World Implementation

Company	Year	Application	Outcome
Tate & Lyle	2024	Large‑scale tagatose production for low‑calorie drinks	Achieved 150 MT/year with a 30 % cost reduction vs.chemical synthesis
Nestlé	2025	tagatose‑sweetened ice cream pilot in Europe	Reported 20 % lower overall calorie content without taste compromise
Cargill	2025	Co‑progress of a “sweet‑blend” using tagatose and stevia	Marketed a sugar‑reduced bakery line that met FDA GRAS status

4. Practical Tips for Food Manufacturers

1. Formulation balance: Blend tagatose with 10‑20 % sucrose to mask any lingering mild caramel notes.
2. Thermal processing: Tagatose remains stable up to 180 °C; incorporate it in baked goods without adjusting cooking time.
3. Shelf‑life testing: conduct accelerated stability studies (40 °C/75 % RH) for at least 6 months to verify no Maillard browning.
4. Regulatory check: Verify GRAS (Generally Recognized As Safe) status in target markets; label as “low‑calorie sweetener” per FDA guidance.

5. Environmental Impact

• Reduced carbon footprint: Fermentation uses renewable glucose derived from corn or sugar beet, cutting CO₂ emissions by ~45 % compared with petroleum‑based sweeteners.
• Water savings: Bioprocessing consumes ~30 % less water than traditional crystallization methods.
• Waste valorization: By‑product glycerol can be recycled into the microbial medium, creating a near‑closed loop system.

6. Frequently asked Questions

• Is tagatose safe for children? Yes; FDA and EFSA have approved tagatose as a safe ingredient for all age groups.
• Does tagatose cause digestive discomfort? in doses >30 g per day,some individuals may experience mild bloating; typical food applications stay well below this threshold.
• Can tagatose be used in alcoholic beverages? Absolutely—its low fermentability means it does not increase alcohol content, making it ideal for low‑calorie beers and cocktails.

7. Future directions

1. CRISPR‑based strain optimization: Researchers at MIT are exploring multiplexed gene edits to push tagatose yields beyond 95 %.
2. Pentose integration: Combining glucose and xylose feedstocks could lower raw material costs further, especially when using lignocellulosic hydrolysates.
3. Hybrid bioprocessing: Coupling engineered bacteria with immobilized enzyme reactors promises continuous production lines with minimal downtime.

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References

1. Liu, H. et al. “Metabolic engineering of E.coli for high‑yield tagatose synthesis,” Biotechnol. Adv. 2024.
2. FDA.“GRAS notice No. 430 – Tagatose,” 2023.
3. Nestlé R&D Report. “Tagatose‑sweetened frozen desserts pilot,” internal document, 2025.

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Takeaway: Engineered microbial platforms now deliver tagatose at commercial scale, offering the food industry a naturally derived, low‑calorie sweetener that matches the taste and functionality of sucrose while delivering health, cost, and sustainability benefits.