KENYA STANDARD           KS 940: 2016 
    ICS 67.080.01 
 
 
 
  
 
  
 
 
 
  
  
Head lettuce — Specification 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
 
 
  ©KEBS 2016      Third Edition 2016 
 
 
 
  
 
 
    
                     © KEBS 2016 — All rights reserved iiTECHNICAL COMMITTEE REPRESENTATION : 
 
The following organizations were represented on the Technical Committee: 
:  
Agriculture Food and Fisheries Authority — Horticultural Crops Directorate 
Kenya Flower Council (KFC) 
Kenya Plant Health Inspectorate Service (KEPHIS) 
Ministry of Agriculture, Livestock and Fi sheries — State Department of Agriculture 
Rapid Result Agricultural program 
Consumer Information Network 
Institute of Packaging 
Fresh Produce Exporters Association of Kenya 
Kenya institute of food science and technology. University of Nairobi-Department of Plant science and crop protection 
AAA growers 
Hortimpact program-SNV 
Society of crop Agribusiness advisors  
Kenya Bureau of Standards — Secretariat  
 
REVISION OF KENYA STANDARDS 
 
In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed. Suggestions for 
improvements to published standards, addressed to the Managing Director, Kenya Bureau of Standards, are 
welcome.  
 
  
 
  
 
  
© Kenya Bureau of Standards, 2016 
Copyright. Users are reminded that by virtue of section 6 of the Copyright Act, Cap. 130 of the Laws of Kenya, copyright subsis ts in all 
Kenya Standards and except as provided under section 7 of this act, no Kenya Standard produced by Kenya Bureau of Standards may  be 
reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing from the M anaging 
Director. 
 
 
 
 
  
 
  
 
  
 
  
ISBN 9966-19-588-2 
 
 
  
© KEBS 2016 — All rights reserved           iii  
 
KENYA STANDARD                           KS 940: 2016 
     ICS 67.080.01 
 
 
 
  
 
 
 
  
 
  
  
Head lettuce — Specification  
 
 
 
 
  
 
 
 
  
 
 
 
  
 
 
 
KENYA BUREAU OF STANDARDS (KEBS) 
 
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                     © KEBS 2016 — All rights reserved iv  
Foreword 
 
 This Kenya standard has been prepared by the Horticultural fresh produce technical committee and is in accordance with the procedures of the Kenya Bureau of standards.  
This standard has been developed in recognition of the contribution of the horticultural 
industry towards the Kenyan Economy.It is expected that the standard will promote trade fair 
practices, safeguard the health and safety of the consumer and protect the environment. 
 In the development of this standard reference has been made to the following standards. 
 
UNECE STANDARD FFV-22 
. 
 Acknowledgement is made for the assistance received from these sources. 
 
  
 
 
 
 
  
© KEBS 2006 — All rights reserved          1  
                                                     KS 940: 2016 
 
 
Head lettuce — Specification 
 
1 Scope 
 
This Kenya Standard prescribes quality requirements for head lettuce ( lactuca sativa var 
capitata,Lactuca sativa var.crispa L.- Leaf lettuce ) . (head lettuces including crisphead and 
“iceberg” type lettuces.  
The standard does not apply to produce for industrial processing, produce presented as 
individual leaves, lettuce with root ball or lettuces in pots.   
 
2. Normative references  
The following referenced documents are indispensable for the application of this document. 
For    dated references, only the edition cited applies. For undated references, the latest 
edition of the   referenced document (including any amendments) applies.  
 
CAC/RCP 53-2003, Code of hygienic practice for fresh fruits and vegetables  
 EAS 38, Labelling of pre-packaged foods — Specification  
 
ISO 874, Fresh fruits and vegetables – Sampling  
 
ISO 6633, Fruits, vegetables and derived products — Determination of lead content — Flameless atomic  
 
ISO 7558, Guide to the prepackaging of fresh fruits and vegetables 
 
 
3. Applications  
The purpose of the standard is to define the quality requirements for produce at the market control stage after preparation and packing. 
 
However, if applied at stages after point of sale produce may show in relation to the requirements of the standard: 
 
i) a slight lack of freshness and turgidity  
ii) a slight deterioration due to their development and their tendency to perish. 
 
The holder/seller of produce may not display such produce or offer them for sale, or 
deliver or market them in any manner other than in conformity with this standard. The Holder/seller shall be responsible for observing such conformity 
 
4. Terms and definitions In addition to the terms and  definitions contained in KS 1559, the following shall apply:  
4.1  KENYA STANDARD  
                     © KEBS 2016 — All rights reserved 2bitter 
pronounced bitterness in taste. 
 
4.2 
clean 
free from dirt, dust, insect stains or other foreign substances 
 4.3  
 firm 
the head is compact 
 
4.4 
split or Bust 
the head is open because of over-maturity 
 
4.5 damage any injury that may be due to any of the following causes 
 
4.5.1  
broken mid-ribs 
when more than two outer heal leaves have the mid-rib broken. 
 
4.5.2  freezing when more than three leaves, other than the wrapper leaves, show more than slight injury by 
freezing, by outdoor frost or by storage. 
 
4.5.3  sun-burn the head leaves show a brown discoloration over more than half of the crown of the heads. 
 4.5.4  
disease 
any unhealthy condition caused by any fungus, bacterium, virus or pest. 
 4.6  fresh 
the head is crisp 
 4.7  
head each individual plant   
 4.8  doubles 
the growth of more than one head on the same stem. 
 4.9  
seed-head KS 940:2006  
© KEBS 2016 — All rights reserved  3the heart has become misshapen and hollow through the growth of the center stalk 
deforming the lettuce as the head bolts. 
 
4.10  
similar varietal characteristics  
the heads in any container have the same characteristic leaf growth. 
 
5 Quality requirements  5.1 Minimum requirements  
All head lettuce shall comply with the following requirements.  
In all classes, subject to the special provisions for each class and the tolerances allowed, the 
produce must be : 
5.1.1Intact 
5.1.2 Sound; produce affected by rotting or deterioration such as to make it unfit for 
consumption is excluded 5.1.3 Clean and trimmed i.e. practically free from all earth or other growing medium and 
practically free from any visible foreign matter 
5.1.4 Fresh in appearance  
5.1.5 Practically free from pests/pest damages/disease 
5.1.6 Turgescent 5.1.7 Not running to seed 
5.1.8 Free from abnormal external moisture 
5.1.9  Free of any foreign smell and /or taste 
In the case of lettuce,a redissh discolouration caused by low temperatures during growth, 
isallowed,unless it seriously affects appearance of the lettuce. The roots must be cut close to the base of the outer leaves and must be neat 
 
The development and condition of produce must be such as to enable it : 
5.1.10 Withstand transportation and handling 
 5.1.11 To arrive in a satisfactory condition at the place of destination. 
 
5.2 Classification  All head lettuce shall comply with the minimum requirements  and shall be classified as below: 
 5.2.1 Class I 
 
i)The Head Lettuce in this class shall have wrapper leaves which shall be fresh, free from 
damage and  Of the minimum number and length necessary to protect the head from injury. 
 
ii)The head shall be firm and well formed iii) Free from damage or deterioration impairing edibility 
iv) Free from frost or chill damage. 
 
v) The stems shall be trimmed so that not more than 15 mm remains past the point of 
attachment to the outside wrapper leaves. 
vi) Head lettuce must have a single well formed heart.However in the case of head lettuces 
grown under protection,the heart may be small 
  
                     © KEBS 2016 — All rights reserved 45.2.2. Class II 
 5.2.1 The head lettuce in this class shall comply with the requirements of class I except that; the head may be trimmed of all wrapper leaves. 
 
5.2.2 The head shall be reasonably firm. 5.2.3  Free from damage and deterioration which may seriously impair edibility 
 
The following defects may be allowed provided the produce retains its essential 
characteristics as regards the quality,keeping quality and presentation. 
i)Slight discolouration ii)Slight pest damages 
Head lettuce must have a heart, which may be small. However, in the case of head lettuces 
grown under protection, absence of heart is permissible. 
 6 Sizing 
 
The size shall be determined by unit mass/weight of one unit .  The minimum mass shall be 
150 g. The tolerances shall be as follows 
 
• 40 g when the lightest unit weighs less than 150 g per unit • 100 g when the lightest unit weighs between 150 g and 300 g per unit 
• 150 g when the lightest unit weighs between 300 g and 450 g per unit 
• 300 g when the lightest unit weighs more than 450 g per unit 
 
 7.1 Quality tolerance 
 
Tolerances in quality and size for each container shall be as follows: 
 7.1.1 Class I  
 
Not more than 10 % of head lettuce not complying with the requirement of class I, but 
complying with the requirements class II.  
7. 1.2 Class II  
 
Not more than 10 % of head lettuce not complying with neither the requirements of class II 
nor the minimum requirements, with the exception of produce affected by rotting or any other deterioration rendering it unfit for consumption. 
 7.2 Size Tolerances  
 For both classes, not more than 10 % of head lettuce not complying with the standard size 
but weighing not 
more than 10 % over or under that size.  8. Provisions concerning presentation 
 
8.1.Uniformity 
The content of each package must be uniform and contain only produce of the same origin, 
variety or commercial type, quality and size. KS 940:2006  
© KEBS 2016 — All rights reserved  5However a mixture of lettuce of distinctively different varieties, commercial types and or 
colours may be packed together in a package,provided they are uniform, in quality and, for each variety, commercial type and or colour concerned in origin 
The visible part of the contents of the package must be representative of the entire contents. 
 9 Contaminants  
 
9.1 Pesticide residues 
the produce covered by this standard shall comply with the maximum residue limits for 
pesticides established by the codex alimentarius commission for this commodity 
  
 9.2 Other contaminants 
 The produce covered by this standard shall comply with the maximum levels of the general 
standard for contaminants and toxins in food and feed(CODEX STAN 193-1995). 
 
 
 
 
 
10 HYGIENE 
 10.1  It is recommended  that the produce covered by the provisions of this Standard be 
prepared and handled in accordance  with  the appropriate  sections  of the General  
Principles  of Food  Hygiene  (KS CAC/RCP  1-1969), Code of Hygienic Practice for Fresh Fruits and Vegetables (KS CAC/RCP 53-2003), and other relevant texts such 
as codes of hygienic practice and codes of practice. 
 
10.2  The produce should comply with any microbiological criteria established in 
accordance with the Principles and Guidelines for the Establishment and Application of Microbiological Criteria related to Foods (KS CAC/GL 21-1997). 
 11. Packaging 
The package used shall ensure product safety and integrity.  The packaging material that is 
in contact with the produce shall be of food grade, clean and of a quality such as to avoid causing any external or internal damage to the produce. The use of materials, 
particularly of paper or stamps bearing trade specifications is allowed, provided the 
printing or labelling has been done with non-toxic ink or glue. Packages shall be free from any foreign matter and the material shall be recyclable 
12. Labeling 
 The following information shall be legibly and indelibly marked on the packets containing the 
produce 
i)Name of the produce i.e “head lettuce” and/or commercial type if the contents are not 
visible from the outside. 
ii) Class 
iii) Size code: 
vi) name and physical address of the importer/packer/distributor;  vii) country of origin;  
viii) net weight in kilograms;  
ix) identification code and/or batch number  
                     © KEBS 2016 — All rights reserved 6x) name of the variety or commercial type;  
xi) storage instructions.  
xii) GMO status  
  13.  Sampling   
 
Head lettuce shall be sampled in accordance with the standard KS ISO 874-Fruits and 
vegetables-Sampling.