Comprehensive Analysis of Brewed Tea: Boron Content, Total Antioxidant and Oxidant Capacity, Oxidative Stress, and pH value


Cihan A., Ozel Korlu A. B., Tüzüner B., Yarat A.

BIOLOGICAL TRACE ELEMENT RESEARCH, pp.1-13, 2025 (SCI-Expanded)

  • Publication Type: Article / Article
  • Publication Date: 2025
  • Doi Number: 10.1007/s12011-025-04705-y
  • Journal Name: BIOLOGICAL TRACE ELEMENT RESEARCH
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, Chemical Abstracts Core, EMBASE, Food Science & Technology Abstracts, Pollution Abstracts, Veterinary Science Database
  • Page Numbers: pp.1-13
  • Istanbul Gelisim University Affiliated: Yes

Abstract

Tea is widely recognized as the most consumed beverage in the world after water. In recent years, the connection between tea and health has gained growing attention as a significant research topic. In this study, we evaluated the relationship between tea and health by analyzing the boron content, total antioxidant capacity (TAC), total oxidant capacity (TOC), oxidative stress index (OSI), and pH levels of teas commonly consumed in Türkiye. A total of 42 samples were created from various tea brands and different tea types that are widely consumed in Türkiye. The determination of boron in pulverized and brewed tea samples was carried out using the carminic acid method. Additionally, boron transfer was determined in brewed teas. Brewed tea samples were also examined in terms of pH, TAC, TOC, and OSI. It was determined that all teas contained an average of 11.73 mg/L boron, the amount of boron in domestic teas was lower than in imported teas. It was determined that boron transfer into brewed tea was approximately 30%. The pH values ranged between 4–5. No differences were detected in terms of TAC, TOC, and OSI. Our research shows that tea consumption is safe in terms of boron levels and helps meet daily needs. The OSI of teas is less than 1, so their antioxidant effects can be considered quite good. However, it should be noted that excessive tea consumption can lead to the demineralization of tooth enamel due to low pH levels.