Development of Low-Calorie Sugar and Functional Jujube Food via Biotransformation

Jujube juice already contains sugar. With the right enzymes, you can turn a good chunk of that sugar into D-allulose. That makes the juice a lower-calorie functional ingredient while keeping the fruit matrix intact. A recent study published in Food Science & Nutrition (DOI: 10.1002/fsn3.963) tested exactly that approach.

The problem with sugar in fruit ingredients

Fruit juices bring flavor, color, and nutrition. They also bring glucose and fructose. For food formulators, that sugar load can be a problem when the goal is a reduced-calorie label. Removing sugars from fruit juice often strips flavor and body. Adding sweeteners later complicates the label. The better route might be changing the sugars already present into something less caloric.

D-allulose fits that need. This rare sugar tastes like sucrose, bulks like sugar, and delivers almost no calories. Most formulators source it as a purified powder. But this study asked a different question: can we produce D-allulose inside the fruit ingredient itself?

What the study did

The researchers applied two enzymes to jujube juice: D-glucose isomerase and D-allulose 3-epimerase. These enzymes convert glucose and fructose into D-allulose. The work was done in concentrated jujube juice under optimized reaction conditions. The team then looked at what happened to the sugar profile and what that D-allulose-enriched juice might do physiologically.

This is not just a lab curiosity. Jujube is a high-sugar fruit, and it grows in large volumes. A process that generates allulose in situ could turn a commodity syrup into a functional sweetener system.

Key findings

The numbers are practical. Under the best reaction conditions, D-allulose reached 110 g/L in concentrated jujube juice. That is a meaningful concentration for a sweetener ingredient. At the same time, glucose and fructose dropped significantly.

Parameter	Result
D-allulose produced	110 g/L
Glucose reduction	13.4%
Fructose reduction	18.1%
Physiological response	GLP-1 release, vagal afferent activation, reduced food intake, improved glucose tolerance

The sugar reductions matter. They show real substrate conversion, not a trace reaction. And the physiological findings add another layer. Oral D-allulose induced GLP-1 release and activated vagal afferent signals. That led to reduced food intake and better glucose tolerance in the study model. For formulators, that suggests a satiety angle, not just a sweetness angle.

What this means for manufacturers

If you work with fruit-based sweeteners, this biocatalytic approach gives you a way to rebalance the sugar profile. Instead of blending allulose into a syrup, you generate it from the fruit’s own glucose and fructose. That simplifies sourcing and may support cleaner label claims.

There is also a functional positioning opportunity. D-allulose is already used in reduced-calorie food and beverage systems. Adding the GLP-1 and feeding behavior data points to possible use in weight-friendly or glucose-management products. Jujube itself has a clean, familiar flavor profile. A jujube syrup with built-in allulose could work in sauces, bakery fillings, beverages, or dairy alternatives.

Of course, process economics matter. Enzyme costs, reaction time, and yield at scale will determine whether this works outside the lab. But the proof of concept is strong. The study delivered 110 g/L allulose with measurable sugar reduction in a real fruit juice system.

FAQ

How much allulose did the jujube juice contain? Up to 110 g/L under optimal reaction conditions.

What happened to the original sugars? Glucose dropped by 13.4% and fructose by 18.1%. Those sugars were converted into D-allulose.

Does D-allulose really reduce food intake? In this study, oral D-allulose triggered GLP-1 release and activated vagal afferent signals, which led to reduced food intake and improved glucose tolerance. That is a strong physiological signal for formulators watching the metabolic health space.

Why this matters now

The food industry needs sugars that taste familiar but behave differently in the body. This study offers a practical path: use fruit juice as the factory, not just the carrier. Jujube juice plus two enzymes produces a low-calorie sweetener system with functional potential. That is the kind of result formulators can actually build on. The next step is scale-up. But the direction is clear. Sugar reduction does not have to mean removing the fruit. Sometimes it means converting what is already there.