Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Mar 14;14(6):985.
doi: 10.3390/foods14060985.

Study on the Effects of Tannase on the De Astringency of Pomegranate Juice

Guida Zhu  1 , Longwen Wang  1 , Han Wang  1 , Zihan Chen  1 , Xue Li  1 , Yi Ji  1 , Jing Yu  1 , Ping Song  1
Affiliations

Study on the Effects of Tannase on the De Astringency of Pomegranate Juice

Guida Zhu et al. Foods. .

Abstract

Reducing the punicalagin content is an effective strategy for eliminating the astringency of pomegranate juice. In this study, pomegranate juice was used as the raw material, and tannase was applied to convert punicalagin into ellagic acid and gallic acid. The effects of tannase concentration, reaction time, and temperature on juice deastringency were evaluated, along with the antioxidant and physicochemical properties of the treated juice. The results demonstrated that, under optimal conditions (33.9 U/100 mL tannase, 30 °C, 90 min reaction time), the punicalagin content decreased by 27.8%, while the ellagic acid and gallic acid levels increased by 24.2% and 32.3%, respectively, effectively reducing the juice's astringency. Under these conditions, the total phenolic content reached 110 mg/100 g, with a free radical scavenging capacity of 69.8%, significantly enhancing the juice's antioxidant properties. These results suggest that tannase treatment of pomegranate juice enhances the polyphenol content, thereby improving its health benefits without compromising the product quality.

Keywords: antioxidant; astringency; polyphenol; punicalagin; tannase.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
The production process of tannase and the determination of its enzymatic activity.
Figure 2
Figure 2
Effect of enzymatic hydrolysis time on the contents of punicalagin (A), ellagic acid (B), and gallic acid (C). Different lowercase letters above the bars (a, b, c, d) indicate statistically significant differences between samples. The significance level was set at 0.05.
Figure 3
Figure 3
Effect of enzymatic hydrolysis temperature on the contents of punicalagin (A), ellagic acid (B), and gallic acid (C). Different lowercase letters above the bars (a, b, c, d) indicate statistically significant differences between samples. The significance level was set at 0.05.
Figure 4
Figure 4
Effect of tannase concentration on the contents of punicalagin (A), ellagic acid (B), and gallic acid (C). Different lowercase letters above the bars (a, b, c, d) indicate statistically significant differences between samples. The significance level was set at 0.05.
Figure 5
Figure 5
A comparative analysis of the contents of punicalagin (A), ellagic acid (B), and gallic acid (C) between the blank and experimental groups under optimal experimental conditions. (D) Changes in punicalagin, ellagic acid, and gallic acid content under optimal conditions. Different lowercase letters above the bars (a, b, c, d) indicate statistically significant differences between samples. The significance level was set at 0.05.
Figure 6
Figure 6
Changes in ascorbic acid (VC) (A), total phenol content (TPC) (B) content and DPPH radical scavenging ability (C). Different lowercase letters above the bars (a, b, c, d) indicate statistically significant differences between samples. The significance level was set at 0.05.
See this image and copyright information in PMC

References

    1. Escarcega G.H., Sánchez-Chávez E., Álvarez S.P., Caballero M.S., Parra J.M.S., Flores-Córdova M.A., Salazar N.A.S., Barrios D.L.O. Determination of antioxidant phenolic, nutritional quality and volatiles in pomegranates (Punica granatum L.) cultivated in Mexico. Int. J. Food Prop. 2020;23:979–991. doi: 10.1080/10942912.2020.1760879. - DOI
    1. Roy B., Singh J., Dewan T. A comparative study of antioxidant activity and total phenolic content of fresh juices of some common Indian fruits with their commercial counterparts. Curr. Sci. 2020;118:300–304. doi: 10.18520/cs/v118/i2/300-304. - DOI
    1. El-Guendouz S., Miguel M.G., Neves M.A., Marreiros A. Comparative Study of Some Physicochemical and in vitro Biological Properties of Juices of Four Pomegranate Cultivars. J. Agric. Sci. Technol. 2023;25:1341–1355.
    1. Masuda M., Horinaka M., Yasuda S., Morita M., Nishimoto E., Ishikawa H., Mutoh M., Sakai T. Discovery of cancer-preventive juices reactivating RB functions. Environ. Health Prev. Med. 2023;28:54. doi: 10.1265/ehpm.23-00160. - DOI - PMC - PubMed
    1. Faria G.M.L., Silva E.K. Pulsed electric field, ultrasound and microwave heating based extraction techniques for valorization of pomegranate peel by-products: A review. J. Environ. Chem. Eng. 2024;12:113078. doi: 10.1016/j.jece.2024.113078. - DOI

LinkOut - more resources