ISO 5642:2024

Overview

ISO 5642:2024 establishes the international standard for tea polyphenol extracts, defining their classification and specifying basic quality requirements. These extracts, derived from Camellia sinensis leaves through green extraction processes, are valued for their high antioxidant content, particularly catechins and total polyphenols. This standard applies specifically to tea polyphenol extracts in solid form, providing a globally recognized framework for grading and quality assessment based on chemical characteristics.

The standard supports consistent product quality, facilitates international trade, and promotes the sustainable development of the tea industry. By defining clear chemical thresholds and testing methods, ISO 5642:2024 addresses the need for reliable classification essential to health, food, cosmetic, and medicinal applications.

Key Topics

• Definition of Tea Polyphenol Extracts
  Solid form extracts primarily comprising catechins derived from fresh tea leaves or tea products through accepted extraction, purification, and drying techniques.

• Classification Grades
  Tea polyphenol extracts are classified into three grades (TP-I, TP-II, TP-III) based on total polyphenol and catechin content, reflecting quality and extraction methods used.

• Chemical Requirements

  • Total Polyphenols: Minimum of 40% (TP-I), 70% (TP-II), and 80% (TP-III) by mass fraction.
  • Total Catechins: Minimum of 20% (TP-I), 40% (TP-II), and 50% (TP-III).
  • Caffeine Content: Maximum limits set at 15% (TP-I) and 5% (TP-II and TP-III).
  • Total Ash: Should not exceed 10% (TP-I), 5% (TP-II), and 3% (TP-III).
  • Moisture Content: Maximum of 6% across all grades.

• Sampling and Testing Methods
  Samples are to be collected in accordance with ISO 7516, with chemical analysis performed via standardized ISO test methods:

  • ISO 14502-1 for total polyphenols (colorimetric method).
  • ISO 14502-2 for catechins (high-performance liquid chromatography).
  • ISO 10727 for caffeine content.
  • ISO 7514 for total ash.
  • ISO 7513 for moisture content.

Applications

ISO 5642:2024 plays a pivotal role in various industries where tea polyphenol extracts are utilized:

• Food and Beverage Industry
  Ensures quality control of tea-derived antioxidant ingredients used in health supplements, functional foods, and beverages.

• Pharmaceutical and Nutraceutical Fields
  Provides standardized extract grades critical for manufacturing consistent and efficacious botanical formulations with known polyphenol content.

• Cosmetic Industry
  Supports the use of tea polyphenol extracts in skincare and cosmetic products by verifying purity and active compound levels.

• International Trade and Supply Chain
  Facilitates global commerce of tea polyphenol extracts by harmonizing quality criteria, reducing trade barriers, and promoting fair exchange.

• Sustainability and Industry Development
  Aids in addressing overproduction challenges in tea-growing regions by promoting value-added extraction processes and sustainable resource utilization.

Related Standards

ISO 5642:2024 references several complementary standards critical for comprehensive quality assurance:

• ISO 7513 – Moisture determination of instant tea products.
• ISO 7514 – Total ash content determination for instant tea.
• ISO 7516 – Sampling methods for instant tea in solid form.
• ISO 10727 – Caffeine content determination via high-performance liquid chromatography.
• ISO 14502-1 – Determination of total polyphenols using the Folin-Ciocalteu reagent.
• ISO 14502-2 – Catechins content determination in green tea by HPLC.

Adopting ISO 5642:2024 alongside these standards ensures rigorous testing, uniform classification, and quality consistency of tea polyphenol extracts worldwide.

By implementing ISO 5642:2024, manufacturers, traders, and end-users of tea polyphenol extracts can confidently rely on a standardized approach to product quality-optimizing health benefits, ensuring regulatory compliance, and enhancing sustainability within the global tea industry.