Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties

Meryem Akhan; Nazan Tokatlı Demirok

doi:10.31015/jaefs.2026.2.10

Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties

Abstract

In this study, functional grape vinegar enriched with olive leaf powder was produced and subsequently subjected to ultrasound treatment. Response Surface Methodology (RSM) was used to optimize the ultrasound treatment conditions; amplitude, treatment time, and olive leaf powder concentration were evaluated as independent variables. Total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were considered as response variables. Optimum conditions were determined to be 80% amplitude, 4 min treatment time, and 0.6848% olive leaf powder. Under these conditions, the experimental TPC and DPPH values were determined to be 91.68 mg GAE/100 mL and 70.95%, respectively. Furthermore, the effects of different treatments on the total flavonoid content, color characteristics, and antimicrobial activity of the grape vinegar were also investigated. The results showed that the GV-US+OLP sample was superior to both the control and thermal pasteurization groups in total phenolic and flavonoid content, as well as in antioxidant activity. While limited changes were observed in color parameters, the total color change was lower in the ultrasound-treated and enriched sample. Antimicrobial analysis revealed that only the ultrasound-treated grape vinegar fortified with olive leaf powder (GV-US+OLP) sample exhibited inhibitory activity, particularly against Escherichia coli. Overall, the findings indicate that combining ultrasound with olive leaf powder is an effective approach for improving the functional and microbiological quality of grape vinegar.

Keywords

Antioxidant Activity, Grape Vinegar, Olive Leaf Powder, Optimization, Ultrasound

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Details

Primary Language

English

Subjects

Fermentation Technology, Basic Food Processes, Veterinary Food Hygiene and Technology

Journal Section

Research Article

Authors

Meryem Akhan
0000-0001-8065-8635
Türkiye

Nazan Tokatlı Demirok ^*
0000-0003-1936-9337
Türkiye

Early Pub Date

June 28, 2026

Publication Date

June 29, 2026

Submission Date

March 14, 2026

Acceptance Date

June 6, 2026

Published in Issue

Year 2026 Volume: 10 Number: 2

DOI

https://doi.org/10.31015/jaefs.2026.2.10

IZ

https://izlik.org/JA99KK29FM

APA

Akhan, M., & Tokatlı Demirok, N. (2026). Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties. International Journal of Agriculture Environment and Food Sciences, 10(2), 373-384. https://doi.org/10.31015/jaefs.2026.2.10

AMA

1.Akhan M, Tokatlı Demirok N. Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties. int. j. agric. environ. food sci. 2026;10(2):373-384. doi:10.31015/jaefs.2026.2.10

Chicago

Akhan, Meryem, and Nazan Tokatlı Demirok. 2026. “Optimization of Ultrasound-Assisted Grape Vinegar Fortified With Olive Leaf Powder: Effects on Bioactive and Functional Properties”. International Journal of Agriculture Environment and Food Sciences 10 (2): 373-84. https://doi.org/10.31015/jaefs.2026.2.10.

EndNote

Akhan M, Tokatlı Demirok N (June 1, 2026) Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties. International Journal of Agriculture Environment and Food Sciences 10 2 373–384.

IEEE

[1]M. Akhan and N. Tokatlı Demirok, “Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties”, int. j. agric. environ. food sci., vol. 10, no. 2, pp. 373–384, June 2026, doi: 10.31015/jaefs.2026.2.10.

ISNAD

Akhan, Meryem - Tokatlı Demirok, Nazan. “Optimization of Ultrasound-Assisted Grape Vinegar Fortified With Olive Leaf Powder: Effects on Bioactive and Functional Properties”. International Journal of Agriculture Environment and Food Sciences 10/2 (June 1, 2026): 373-384. https://doi.org/10.31015/jaefs.2026.2.10.

JAMA

1.Akhan M, Tokatlı Demirok N. Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties. int. j. agric. environ. food sci. 2026;10:373–384.

MLA

Akhan, Meryem, and Nazan Tokatlı Demirok. “Optimization of Ultrasound-Assisted Grape Vinegar Fortified With Olive Leaf Powder: Effects on Bioactive and Functional Properties”. International Journal of Agriculture Environment and Food Sciences, vol. 10, no. 2, June 2026, pp. 373-84, doi:10.31015/jaefs.2026.2.10.

Vancouver

1.Meryem Akhan, Nazan Tokatlı Demirok. Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties. int. j. agric. environ. food sci. 2026 Jun. 1;10(2):373-84. doi:10.31015/jaefs.2026.2.10

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Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties

Optimization of ultrasound-assisted grape vinegar fortified with olive leaf powder: effects on bioactive and functional properties

Abstract

Keywords

References

Details

Primary Language

Subjects

Journal Section

Authors

Early Pub Date

Publication Date

Submission Date

Acceptance Date

Published in Issue

DOI

IZ

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