Developing Low-Calorie Sugar and Functional Jujube Food Using Biotransformation

Opening

Jujube juice is full of glucose and fructose. That makes it sweet, but it also makes it a problem in low-calorie formulations. A study published under DOI 10.1002/fsn3.963 took those natural sugars and converted them into D-allulose. The process worked. The juice ended up with 110 g/L of D-allulose.

Background

The research sits at the intersection of sugar reduction and functional foods. The paper’s stated goal is low-calorie sugar development and functional jujube food. The solution was biotransformation. Two enzymes did the work. D-glucose isomerase converts glucose into fructose. D-allulose 3-epimerase converts fructose into D-allulose. Jujube juice was the feedstock because it already contains both glucose and fructose.

What the study did

The team applied these enzymes to concentrated jujube juice. They optimized the reaction conditions. The conversion happened directly in the juice matrix. That is different from typical sugar reduction approaches, which remove sugar first and add a sweetener later.

D-allulose accumulated to 110 g/L. The original sugar levels changed. Glucose went down 13.4%. Fructose went down 18.1%. The product was not sugar-free. It had a different sugar profile, with lower glucose and fructose and meaningful amounts of D-allulose.

The study did not stop at sugar composition. Oral D-allulose also triggered GLP-1 release and activated vagal afferent signaling. Those effects reduced food intake and improved glucose tolerance. That gives the ingredient a functional dimension.

Key findings

| Component / Step | Enzyme or action | Observed result | | Glucose in jujube juice | D-glucose isomerase | Glucose content down 13.4% | | Fructose in jujube juice | D-allulose 3-epimerase | Fructose content down 18.1% | | D-allulose | Accumulated in concentrated juice | 110 g/L | | Oral D-allulose | GLP-1 release + vagal afferent activation | Reduced food intake, improved glucose tolerance |

The numbers give formulators a clear benchmark. 110 g/L is a working concentration, not a trace. The 13.4% glucose drop and 18.1% fructose drop show the enzymes shifted a measurable portion of the sugar pool.

What it means for manufacturers

This is an in situ approach. You do not need to strip the juice down and rebuild it. The enzymes transform part of the fruit’s own sugar into a low-calorie sweetener. That could simplify ingredient sourcing and label strategy. You keep the fruit base and change its sugar composition.

For ingredient buyers, the key issue is process scalability. The enzymes are known, but reaction conditions matter. Ask suppliers how they run the enzymatic step at scale. Ask for the final D-allulose concentration and the residual glucose and fructose levels. The study’s 110 g/L result provides a useful reference point.

The physiological results open another door. D-allulose is not just a bulking sweetener. It showed bioactivity in this study. That may appeal to formulators developing products for appetite control or glucose management.

FAQ

Why did the researchers use jujube juice?

Because it contains glucose and fructose, the exact substrates for the two enzymes. The juice acts as both the flavor base and the reaction medium.

Did the conversion remove all the sugar?

No. Glucose fell 13.4% and fructose fell 18.1%. Some glucose and fructose remained. D-allulose joined them at 110 g/L.

What makes this more than a sweetener swap?

Oral D-allulose induced GLP-1 release and activated vagal afferent signals. The result was reduced food intake and improved glucose tolerance.

Closing

You can now look at jujube juice differently. It is not only a sweet fruit ingredient. It is a substrate for low-calorie sugar production. The enzymes did the work, and the juice carried it. That is a practical route for food developers who want sugar reduction without losing the fruit.