KENYA STANDARD            KS 789: 2016 
        ICS 67.080.20 
 
 
 
  
 
  
 
 
 
  
  
 Fresh bulb onions — Specification 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
 
 
  ©KEBS 2016            Second  Edition 2016 
 
 
 
  
 
 
 
 
 
 KS 789: 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. 
 
 
 
  
 
  
 
  
 
  
  
© KEBS 2016 — All rights reserved           iii ISBN 9966-19-586-6 
 
 
  
 
KENYA STANDARD
                          KS 789: 2016 
     ICS 67.080.20 
 
 
 
  
 
 
 
  
 
 
 
  
Fresh bulb onions — Specification 
  
 
 
 
 
 
 
KENYA BUREAU OF STANDARDS (KEBS) 
 
Head Office:  P.O. Box 54974, Nairobi-00200, Tel.: (+254 020) 605490, 602350, Fax: (+254 020) 604031 
E-Mail: info@kebs.org,  Web:http://www.kebs.org   
Coast Region   
 Lake Region     
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P.O. Box 2138, Nakuru-20100 Tel.: (+254 041) 229563, 230939/40               Tel.: (+254 057) 23549, 22396       Tel.: (+254 051) 210553, 210555 
Fax: (+254 041) 229448  
 Fax: (+254 057) 21814  
 
 
  
 
 
 KS 789: 2016  
                     © 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 expecte d 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-25  ONIONS 
 
Acknowledgement is made for the assistance received from these sources 
© KEBS 2006 — All rights reserved          1  
                                                     KS 789: 2016 
 
 
Fresh bulb onions — Specification 
 
1.Scope 
This Kenya standard applies to onions of varieties (cultivars) grown from Allium cepa  L. 
Cepa Group to be supplied to the consumer in the natural state, green onions with full leaves 
and Onions for industrial processing being excluded. 
 
 
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. Application 
 
The standard is to define the quality requirements for fresh bulb onions after preparation and 
packaging. 
However, if applied at stages after point of sale or following export, 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 
clean 
free from dirt, dust, insect, stains or other foreign substances and material 
 
4.2 decay  
soft or dry rot 
 KENYA STANDARD  
                     © KEBS 2016 — All rights reserved 24.3 
firm 
the onion, which may yield slightly to moderate finger pressure 
 
4.4 
damage 
any defect or injury, which affects the appearance or storage quality of the onions 
 
4.5 
disease  
any unhealthy condition caused by any fungus bacterium, virus or pest 
 
4.6  
doubles 
onions which have developed more than one distinct bulb joined only at the base, whether 
the outer skin is broken or otherwise  
4.7 
size 
the maximum diameter of the bulb along the equatorial section 
 
4.8 
seed stem 
the bulb heart, which has become misshapen and hollow through the center stem deforming 
the onion 
 
4.9 malshaped bulbs 
bulbs with seed stems and /or with abnormal swelling 
 
4.10 
intact 
(Outer Skin Included) Onions which have not suffered any mutilation during growth or at the 
time of pulling, drying, removing the stem, packing, handling or any other operations 
 
4.11 
sound 
onions which are free from any rot, disease and damage 
 
 
4.12 
sufficiently dry 
onions which are sufficiently firm and do not become soft or spongy to moderate finger 
pressure, the neck being fairly dry  
 
5 Quality requirements 
 
5.1 Minimum requirements  
 
In all classes, subject to the special provisions for each class and the tolerances allowed, the 
Bulb onions  shall  be: KS 789: 2006  
© KEBS 2015 — All rights reserved  35.1.1 intact 
5.1.2 Sound; produce affected by rotting or deterioration such as to make it unfit for 
Consumption is excluded 5.1.3 Clean, practically free of any visible foreign matter 
5.1.4 Fresh in appearance 
5.1.5 Free from parchment (hard endoderm) 
5.1.6 Practically free from pests 
5.1.7 Practically free from damage caused by pests 5.1.8 Free of abnormal external moisture 
5.1.9 Free of any foreign smell and/or taste. 
 
The development and condition of the bulb onions must be such as to enable them: 
 5.1.10 to withstand transportation and handling 
5.1.11 to arrive in satisfactory condition at the place of destination 
 
 
5.2. Classification 
onions are classified into two classes, as defined below: 
 (i) Class I 
Onions in this class must be of good quality. They must be characteristic of the variety 
and/or commercial type. 
The bulbs must be: a) firm and compact 
b)free from externally visible shoots 
c free from swelling caused by abnormal vegetative development d) practically free of root tufts; however, for onions harvested before complete 
maturity, root tufts are allowed. 
 
The following slight defects, however, may be allowed, provided these do not affect the 
general appearance of the produce, the quality, the keeping quality and presentation in the package: 
a) a slight defect in shape 
b) slight defect s in colouring 
c) light staining that does not affect the outer skin, provided it does not cover more 
than one fifth of the bulb’s surface d) superficial cracks in and partial absence of the outer skins, provided the flesh is 
protected. 
(ii) Class II 
This class includes onions that do not qualify for inclusion in Class I but satisfy the 
minimum requirements specified above. The bulbs must be reasonably firm. 
The following defects may be allowed, provided the onions retain their essential 
characteristics as regards the quality, the keeping quality and presentation: 
a) defects in shape 
b) defects in colouring c) traces due to rubbing 
d) slight marking caused by parasites or disease 
e)small healed cracks f) slight healed bruising 
g) root tufts 
  
                     © KEBS 2016 — All rights reserved 4h)stains that do not affect the outer skin, provided they do not cover more than half the 
bulb’s surface 
i) cracks in the outer skins and partial ab sence of the skins over a maximum of one 
third of the bulb’s surface, provided the flesh is not damaged. 
 
 
 
6.0 Provisions concerning tolerances 
 
At all marketing stages, tolerances in respect of quality and size shall be allowed in each lot 
for produce not satisfying the requirements of the class indicated.  
6.1 Quality tolerances 
 
(i) “Extra” Class 
A total tolerance of 5 per cent, by number or weight, of beans not satisfying the requirements of the class but meeting those of Cl ass I is allowed. Within this tolerance not 
more than 0.5 per cent in total may consist of produce satisfying the requirements of 
Class II quality. 
 
(ii) Class I A total tolerance of 10 per cent, by number or weight, of beans not satisfying the 
requirements of the class but meeting those of Class II is allowed. Within this tolerance not 
more than 1 per cent in total may consist of produce satisfying neither the requirements of 
Class II quality nor the minimum requirements, or of produce affected by decay. No 
tolerance is allowed for produce affected by Colletotrichum lindemuthianum (bean spot 
disease). 
Within this tolerance, a maximum of 5 per cent, by number or weight, may have strings in 
the case of a variety and/or commerci al type that should be stringless. 
In addition, a maximum of 15 per cent, by number or weight, of beans (excluding needle 
beans) may have the stalk and a small section of the narrow part of the neck missing. provided these pods remain closed, dry and not discoloured 
 
(iii) Class II 
A total tolerance of 10 per cent, by number or weight, of beans satisfying neither the 
requirements of the class nor the minimum requ irements is allowed. Within this tolerance 
not more than 2 per cent in total may consist of produce affected by decay. No tolerance is 
allowed for produce affected by Colletotrichum lindemuthianum (bean spot disease). 
In addition a maximum of 30 per cent, by number or weight, of beans (excluding needle 
beans) may have the stalk and a small section of the narrow part of the neck missing, 
provided these pods remain closed, dry and not discoloured.  
7.0 Provisions concerning sizing 
Size is determined by the maximum diameter of the equatorial section. 
The minimum diameter shall be 10 mm. 
To ensure uniformity in size, the range in size between produce in the same package shall 
not exceed: 
• 5 mm where the diameter of the smallest onion is 10 mm and over but under 20 mm. 
However, where the diameter of the onion is 15 mm and over but under 25 mm, the difference may be 10 mm 
• 15 mm where the diameter of the smallest onion is 20 mm and over but under 
40 mm KS 789: 2006  
© KEBS 2015 — All rights reserved  5• 20 mm where the diameter of the smallest onion is 40 mm and over but under 
70 mm • 30 mm where the diameter of the smallest onion is 70 mm or over. 
 
7.1 Size tolerances 
For all classes (if sized): a total tolerance of 10 per cent, by number or weight, of beans not 
satisfying the requirements as regards sizing is allowed. 
  
 
 
 
 
 
8.0 Provisions concerning presentation 
 8.1 Uniformity 
The contents of each package (or lot for produce presented in bulk in the transport vehicle) 
must be uniform and contain only onions of the same origin, variety or commercial type, 
quality and size. 
However, a mixture of onions of distinctly different commercial types and/or colours may 
be packed together in a sales package, provided they are uniform in quality and, for each 
commercial type and /or colour concerned, in origin. 
The visible part of the contents of the package (or lot for produce presented in bulk in the 
transport vehicle) 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.   
                     © KEBS 2016 — All rights reserved 610.2  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 “bulb onions” 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 
x) name of the variety or commercial type;  
xi) storage instructions.  
xii) GMO status 
 
13.   Sampling   
 
Beans shall be sampled in accordance with the standard KS ISO 874-Fruits and 
vegetables-Sampling.