ISO/TR 21380:2022 抹茶—定義と特徴 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 34 Food products, Subcommittee SC 8, Tea.

Introduction

Tea is grown and manufactured in numerous countries in the world and is blended and/or consumed in many more. There is some confusion as to the origins, cultivation, appearance and processing for matcha tea and how this can or does differ from green, black, white and other types of tea.

Matcha tea (see Figure A.1) is traditionally prepared with hot water as a beverage in the Japanese tea ceremony called “Chanoyu”. Matcha tea is now consumed as a tea beverage prepared with hot water worldwide. In modern usage, matcha tea is also an ingredient in food and beverages.

The desired characteristics of matcha tea and the resulting liquor infusion depend upon a number of factors including the tea plant cultivation and the unique processing method and manufacture using fresh tea leaves.

This document:

• specifies the plant source of matcha tea;
• explains the requirements for cultivation, processing (drying) and grinding;
• identifies the physical and chemical characteristics which, if met, identify that the tea has followed good manufacturing practice.

The cultivation and processing methods are presented as the typical examples which have been developed for the harvest of tencha tea leaves (see Figure A.2) and the production of matcha tea in Japan.

Matcha tea is a specific type of green tea prepared with plant cultivation using shading, leaf steaming and leaf grinding processes. An investigation of the levels of L-theanine, chlorophyll and catechins – including epigallocatechin gallate (EGCG) and epigallocatechin (EGC) – in matcha tea indicates that the levels can vary to those in green and black teas and shows they support the discrimination between matcha, green and black teas. It is possible that the differentiation between matcha, green and black teas needs the use of ratios of the various chemical components, among others.

1 Scope

This document contains information regarding the tea cultivation, manufacture (including processing and grinding) and sensory analysis of the tea referred to as “matcha tea” in international trade.

It provides an internationally agreed definition of matcha tea based on the plant source, cultivation and production methods used. These are important for the physical, chemical and sensory characteristics of matcha tea.

It does not apply to flavoured matcha tea, blended matcha tea, or decaffeinated or soluble extracts of matcha tea.

2 Normative references

There are no normative references in this document.

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

Bibliography