Development of Low-Calorie Sugars and Functional Jujube Foods via Biotransformation

Jujube Juice as a Sweetener Base

Jujube juice is sweet, but its sweetness comes with calories. That may be about to change. A paper in Food Science & Nutrition (DOI: 10.1002/fsn3.963) shows how enzymes can turn the natural sugars in jujube juice into D-allulose, a low-calorie sweetener. The process works, and the resulting sweetener has a functional side.

The Sugar Problem in Jujube

Ripe jujube carries a heavy load of glucose and fructose. Those sugars taste good, but they raise the calorie count of whatever you put them in. For formulators, that is a real limitation. You cannot rely on jujube alone when you need sweetness without the metabolic load. This study offers another route: convert the juice’s own sugars into something better.

What the Study Did

The researchers applied two enzymes to concentrated jujube juice: D-glucose isomerase and D-allulose 3-epimerase. That enzyme pair converts glucose and fructose into D-allulose. Under optimal reaction conditions, the juice began accumulating D-allulose instead of just carrying its original sugars.

The results were clear. D-allulose concentration reached 110 g/L. Glucose and fructose did not disappear completely, but they dropped by 13.4% and 18.1%, respectively.

Key Findings

Here are the main numbers from the study:

Parameter	Finding
D-allulose concentration	110 g/L
Glucose reduction	13.4%
Fructose reduction	18.1%
D-allulose bioactivity	Stimulates GLP-1 release, activates vagal afferent signals, reduces food intake, improves glucose tolerance

The physiological side matters just as much as the sugar chemistry. Oral D-allulose triggered GLP-1 release and sent signals through the vagus nerve. Those signals led to reduced food intake and improved glucose tolerance. D-allulose is not just a sugar replacement. It has biological activity.

What It Means for Manufacturers

For formulators, this points to a practical way to generate low-calorie sweetness inside a fruit ingredient. You do not need to source isolated D-allulose and add it into the formula later. The enzymes do that work in the jujube juice itself.

For ingredient buyers, this changes how you evaluate jujube. A standard fruit concentrate could become a functional sweetener base. The dual profile is rare. You get low-calorie sweetness plus the satiety and glucose-regulating effects tied to GLP-1.

The 110 g/L benchmark gives you a realistic target for what the enzyme system can achieve in a concentrated juice matrix. Reaching that number in production will depend on controlling enzyme activity, temperature, substrate levels, and reaction time. But the technical baseline is now on the table.

Questions Formulators Ask

Which enzymes were used? D-glucose isomerase and D-allulose 3-epimerase. Together, they convert glucose and fructose in jujube juice into D-allulose.

How much D-allulose was produced? In concentrated jujube juice, D-allulose reached 110 g/L. Glucose fell by 13.4% and fructose by 18.1%.

Does D-allulose only sweeten? No. Oral D-allulose stimulated GLP-1 release, activated vagus nerve signaling, reduced food intake, and improved glucose tolerance.

The commercial angle is straightforward. Jujube juice with built-in D-allulose can support reduced-calorie sweetening and functional food development at the same time. The enzyme step is specific, the results are measurable, and the physiological benefit gives you a product story that ordinary sugar cannot tell.