Stevia in kale juice spheres during refrigerated storage
What it found
Adding stevia to kale juice spheres improved flavour without harming quality over 7 days in the fridge.
The sulforaphane content stayed the same.
What they found
Studies in people
Sensory quality
Stevia smoothed the bitter flavour. The 1.25 and 2.5 g per litre samples scored highest for flavour and overall quality after 7 days.
Other findings
Physical quality
Stevia did not affect the spheres' diameter or surface. The spheres had high mechanical resistance and low swelling.
Colour changes
The spheres with the most stevia (2.5 g per litre) had the least colour change after 7 days. Stevia did not cause colour changes at the start.
Microbiological quality
All spheres stayed below 7 log CFU per gram throughout storage, regardless of stevia concentration. Stevia did not show antimicrobial effects at these levels.
Sulforaphane content
The sulforaphane content of kale spheres was not affected by stevia over the 7-day period.
What the authors conclude
“Stevia addition to the kale juice spheres led to a better flavour without altering the product quality during refrigerated storage.”
Also in their conclusions
- They say stevia addition to kale juice spheres led to a better flavour without altering product quality during refrigerated storage.
- They state that the sulforaphane content of kale spheres was not affected by the sweetening with the studied stevia concentrations throughout 7 days.
How it was done
Kale is rich in health-promoting compounds but its bitter flavour limits how much people drink it. Sweetening with stevia could mask the bitterness.
Kale juice spheres were made with a double spherification technique and stored at 5°C for 7 days. Different amounts of stevia extract were added: none, 0.5, 1.25 and 2.5 grams per litre.
What it can’t tell you
- This study looked only at quality changes during storage, not at health effects in people.
- It cannot show what would happen with other amounts of stevia or different storage conditions.
Who paid
- Funding
- Funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico; Sacoje SCL; Sakata Seeds Ibérica SLU (from the PubMed record).
- Authors work at
- Institute of Plant Biotechnology, Spain
The paper
- Title
- Effect of stevia supplementation of kale juice spheres on their quality changes during refrigerated shelf life
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Klug TV, Collado E, Martínez-Hernández GB, Artés F, Artés-Hernández F (2019). Effect of stevia supplementation of kale juice spheres on their quality changes during refrigerated shelf life. Journal of the science of food and agriculture. doi:10.1002/jsfa.9445Free full textPubMed 30357844DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error