ISO 20716:2022

INTERNATIONAL ISO
STANDARD 20716
First edition
2022-09
Oolong tea — Definition and basic
requirements
Thé Oolong — Définition et caractéristiques de base
Reference number
© ISO 2022
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Published in Switzerland
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 N ormative references . 1
3 T erms and definitions . 1
4 R equirements . 2
4.1 General requirements . 2
4.2 Manufacturing requirements . 2
4.2.1 Harvest . 2
4.2.2 Withering . 2
4.2.3 Tumbling and aeration . 2
4.2.4 Enzyme inactivation . 2
4.2.5 Shaping . 2
4.2.6 Drying . 3
4.3 S ensory analysis . 3
4.4 Chemical requirements . . 3
5 S ampling . 3
6 P acking, storage and marking. 3
6.1 Packing . 3
6.2 S torage . 4
Annex A (informative) Typical manufacturing process of oolong tea . 5
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 8,
Tea.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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Introduction
Tea is grown and manufactured in numerous countries of the world and is blended or drunk in many
more.
The desired characteristics of an oolong tea and the resulting liquor depend upon a number of factors,
including the type of water to be used for brewing, the preparation method, the degree of aeration/
oxidization (formerly known as “fermentation”), the variety of tea plant and the unique processing
method using fresh tea leaves. Oolong tea is a partially aerated/oxidized tea and, as such, the bruised
edges of withered leaves and enzyme deactivation are compulsory processes.
This document specifies the plant source from which the oolong tea is to be manufactured, the process
of making oolong tea, and requirements for certain chemical characteristics which, if met, are an
indication that the tea has been subjected to good manufacturing practice.
The quality of oolong tea is usually assessed sensorially by skilled tea tasters, who base their judgements
on their previous experience of oolong tea, their knowledge of the conditions in the producing areas,
and the preferences of the consuming country. A number of factors are considered when evaluating the
quality of oolong tea, including the appearance of the dry tea leaf (such as shape, colour, cleanliness and
evenness), the appearance and odour of the infused leaf, and the appearance, odour and taste of the tea
liquor. In practice, teas are submitted for chemical analysis only if a tea taster suspects that the product
has been adulterated, or if it exhibits abnormal characteristics.
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