Alkaline ionized water increases green tea polyphenols by up to 2.8 times

New potential benefits of alkaline ionized water

Osaka, Japan, April 3, 2025 – Panasonic Corporation today announced that its Living Appliances and Solutions Company (Panasonic) has confirmed that green tea made with alkaline ionized water contains up to 2.8 times more polyphenols than green tea made with natural drinking water. This was achieved through joint research with Panasonic Appliances (China) Co., Ltd., Panasonic R&D Center Suzhou Co., Ltd., and Bei Wang, a professor at the School of Food and Health, Beijing Technology and Business University.

In recent years, the number of people regularly drinking water has been increasing due to heightened health awareness, leading to a growing demand for safe and healthy water. The government is also considering strengthening the legal regulations related to water quality and reviewing the standards for water quality. Furthermore, many people use water purifiers to filter water before drinking it.

Under such circumstances, as part of the personal care business, Panasonic recognized the potential of green tea,*¹, *² which is frequently consumed and offers various health benefits from its polyphenol content. Panasonic conducted joint research with Professor Bei Wang, a food science specialist in China, the world's largest producer of green tea. A verification using alkaline ionized water with different pH values showed that the amount of polyphenols contained in green tea is greater when using alkaline ionized water than natural drinking water, and the higher the alkalinity, the higher the polyphenol content. It is hoped that this will enable tea to contain abundant polyphenols derived from green tea when brewed with alkaline ionized water. Please note that these are the results of the verification test described later and do not guarantee the effects in the actual usage environment or when drinking.

With the aim of contributing to society by providing safe and secure drinking water, Panasonic will continue improving water purification and conditioning technology while pursuing its potential.

Comments from Professor Bei Wang*³

Tea polyphenols are essential components that determine the color, aroma, taste, and efficacy of tea leaves. They are also among the most important functional components of green tea, which has numerous health benefits, such as oxidation resistance, blood lipid adjustment, virus resistance, antibacterial effects, tumor resistance, and neuroprotection. The results of an omnibus experiment conducted at a laboratory in Beijing Technology and Business University revealed that green tea made with alkaline ionized water (pH values 8.14, 8.79, and 9.19) produced by Panasonic's alkaline water ionizer contains more tea polyphenols than green tea made with unprocessed natural drinking water. This discovery not only provides valuable experiences to tea lovers, but it has also successfully harmonized modern science and technology with traditional food culture.

Profile

Bei Wang: Professor, Doctor Supervisor, and Assistant Dean of School of Food and Health, Beijing Technology and Business University. Professor Wang has extensively conducted big data research on food flavor and sensory omics and has been involved in more than 40 projects related to the food flavor and nutrition science, some of which were supported both by National Natural Science Foundation of China, . She has also published more than 100 high-level SCI research papers and obtained nearly 20 invention patents in China, as well as two USA patents and three software copy right. In addition, she has won first prize at the Shanghai Science and Technology progress Awards, first prize of China Business Federation Science and Technology Progress Award, and First Prize of the State Administration for Market Regulation Research Achievement Award for Market Regulation of China.

■Verification test

Figure 1 Measurement of the amount of polyphenols

Verification agency: School of Food and Health, Beijing Technology and Business University
Verification method: Alkaline ionized water with pH values of 8.14, 8.78, and 9.19 was generated from commercially available natural drinking water (pH 7.68) using an alkaline water ionizer and heated to 85°C. Then, 150 ml of heated alkaline ionized water was poured into a container with 3.0 g of tea leaves, and the amount of polyphenols was measured after four minutes (Figure 1).

■Verification results

Figure 2 Polyphenol content in green tea

When green tea was made with natural drinking water, the polyphenol content was 0.090 mg/mL. Meanwhile, when green tea was made with alkaline ionized water, the content increased by up to 2.8 times, with 0.206 mg/mL (pH 8.14), 0.212 mg/mL (pH 8.78), and 0.253 mg/mL (pH 9.19) (Figure 2).

■What is alkaline ionized water?

Figure 3 Generation of alkaline ionized water using electrolysis technology

Alkaline ionized water is generated by electrolyzing filtered, purified water in an electrolytic cell. The cathode (negatively charged electrode) attracts hydroxide ions and hydrogen, generating alkaline ionized water, while the anode (positively charged electrode) attracts hydrogen ions and oxygen, generating mildly acidic water (Figure 3).

Notes:

*1 Reference: Saori Nakagawa, Takahiro Hoshi, Atsushi Kubo, and Susumu Yamato, "Determination of Tea Polyphenols in Bottled Japanese Tea Drinks and Differences in Polyphenol Content in Tea Leaves from Different Variety," BUNSEKI KAGAKU, vol. 62, No. 1, pp. 51-55, 2013

*2 Reference: Hirofumi Tachibana, "Molecular Nutritional Study on the Bioregulatory Effects of Green Tea Polyphenols," Journal of Japan Society of Nutrition and Food Science, vol. 72, No. 5, pp. 205-210, 2019

*3 Panasonic asked Professor Wang for comments and edited them for publication.

Media Contact:

Living Appliances and Solutions Company, Panasonic Corporation
Public Relations, Corporate Policy Department, Corporate Planning Center
Email: las-pr@gg.jp.panasonic.com

About Panasonic Corporation

Panasonic Corporation offers products and services for a variety of living environments, ranging from homes to stores to offices and cities. There are five businesses at the core of Panasonic Corporation: Living Appliances and Solutions Company, Heating & Ventilation A/C Company, Cold Chain Solutions Company, Electric Works Company and China and Northeast Asia Company. The operating company reported consolidated net sales of 3,494.4 billion yen for the year ended March 31, 2024. Panasonic Corporation is committed to fulfilling the mission of Life Tech & Ideas: For the wellbeing of people, society and the planet, and embraces the vision of becoming the best partner of your life with human-centric technology and innovation. Learn more about Panasonic: https://www.panasonic.com/global/about/

スクロールできます

The content in this website is accurate at the time of publication but may be subject to change without notice.
Please note therefore that these documents may not always contain the most up-to-date information.
Please note that German, French and Chinese versions are machine translations, so the quality and accuracy may vary.