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 20716:2022(E)
© ISO 2022

---------------------- Page: 1 ----------------------
ISO 20716:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2022 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 20716:2022(E)
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
© ISO 2022 – All rights reserved

---------------------- Page: 3 ----------------------
ISO 20716:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
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
complete listing of these bodies can be found at www.iso.org/members.html.
iv
  © ISO 2022 – All rights reserved

---------------------- Page: 4 ----------------------
ISO 20716:2022(E)
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.
v
© ISO 2022 – All rights reserved

---------------------- Page: 5 ----------------------
I
...