Developing Low-Calorie Sugars and Functional Jujube Foods Through Biotransformation

Jujube Juice Becomes a Low-Calorie Sweetener Source

Forget adding D-allulose to jujube products. This research starts with the jujube itself. A team applied two enzymes to jujube juice and turned the juice’s own sugars into D-allulose. Under optimized conditions, that conversion reached 110 g/L. That is a production-relevant number, not a lab curiosity.

Why D-allulose matters

D-allulose is a low-calorie sweetener with real metabolic potential. It has caught attention because it does more than replace sugar. The abstract of this paper reports that oral D-allulose induces GLP-1 release and activates vagal afferent signaling. Those signals reduce food intake and improve glucose tolerance.

But D-allulose needs a practical source. Jujube, or red date, is already familiar in food formulations. It contains both glucose and fructose. Those are exactly the sugars you need to make D-allulose. The study turns that natural sugar pool into something more valuable.

What the researchers did

The team worked with concentrated jujube juice. They used two enzymes: D-glucose isomerase and D-allulose 3-epimerase. The first enzyme converts glucose into fructose. The second converts fructose into D-allulose. By optimizing reaction conditions, they pushed the system toward meaningful D-allulose production.

This is a biotransformation, not a chemical synthesis. The starting material stays recognizable as jujube juice. The sugar profile changes, but the product remains a food ingredient. That matters for formulators who want clean processing steps and familiar raw materials.

A 110 g/L shift in the sugar profile

The key result is simple: D-allulose appeared at 110 g/L in concentrated jujube juice. At the same time, glucose dropped by 13.4% and fructose dropped by 18.1%.

Sugar	Change after biotransformation
D-allulose	Produced at 110 g/L
Glucose	Reduced by 13.4%
Fructose	Reduced by 18.1%

Those changes mean the juice now contains a substantial amount of low-calorie sweetener. It also means the sweetness does not disappear. The remaining glucose and fructose still contribute, but the overall sugar composition tilts toward D-allulose.

The physiological evidence adds another layer. D-allulose triggered GLP-1 release and activated vagal afferent signals. That led to reduced food intake and improved glucose tolerance. So this is not just a sugar swap. The target compound carries functional weight.

What formulators and buyers can take from this

First, jujube juice can serve as its own sugar source. You do not need a separate fructose stream to start D-allulose production. The enzymes handle the conversion inside the juice.

Second, functional positioning becomes possible. A jujube-based sweetener could be marketed as more than a low-calorie option. The metabolic effects described in the paper give product developers a story backed by measurable endpoints like GLP-1 release and glucose tolerance.

Third, this opens a route for upcycling or upgrading existing fruit ingredients. Jujube is not an exotic raw material in many markets. Turning its natural sugars into D-allulose adds value without introducing artificial processing steps.

Ingredient buyers should watch for enzyme systems that work directly in fruit juices. The combination of glucose isomerase and D-allulose 3-epimerase is the core of this process. Ask suppliers whether they can handle concentrated juice matrices and whether the conversion holds at scale.

Questions you might ask

Which enzymes did the study use? The process used D-glucose isomerase and D-allulose 3-epimerase. These work sequentially to convert glucose to fructose, then fructose to D-allulose.

How much D-allulose did they get? Under optimal conditions, D-allulose reached 110 g/L in concentrated jujube juice. Glucose and fructose fell by 13.4% and 18.1%, respectively.

What metabolic effects did D-allulose show? Oral D-allulose induced GLP-1 release and activated vagal afferent signaling. The result was reduced food intake and improved glucose tolerance.

Jujube is no longer just a dried fruit or a traditional ingredient. It can be a production platform for a low-calorie sweetener with metabolic benefits. The numbers are clear, and the physiological signals point the same direction. For food brands looking to cut sugar while keeping natural ingredients, this enzyme route deserves serious evaluation.