KENYA STANDARD  DKS/2993 :2023  
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First Edition  
  
 © KEBS 2023  
 Raw Walnut  Kernels— Specification    
 
  
 
 
KENYA STANDARD  DKS 2993 :2023  
ICS ##.###  
First  Edition  
 
© KEBS 2023  – All rights reserved  ii 
  TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
Agriculture and Food Authority - Nuts and Oil Crops Directorate  
Government Chemist's Department  
Jungle Nuts Ltd.  
Kakuzi PLC  
Kenya Agricultural and Livestock Organization  
Kenya Industrial Research and Development Institute  
Kenya Nut Company Limited  
Kenyatta University  
Kenya Plant Health Inspectorate Service (KEPHIS)  
Ministry of Health  
National Public Health Laboratories  
Sagana Nuts Limited  
SGS Kenya Limited  
Syncom Food Consultancy Ltd.  
Tensenses Africa EPZ Ltd.  
Topnuts Enterprises Ltd.  
Agventure  Ltd  
Healthy U 2000 limited  
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, 2024  KENYA STANDARD  DKS 2993 :2023  
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First  Edition  
 
© KEBS 2023  – All rights reserved  iii 
  Copyright. Users are reminded that by virtue of Section 25 of the Copyright Act, Cap. 130 of 2001 of the Laws of Kenya, copyr ight subsists in all Kenya Standards and 
except as provided under Section 25 of this Act, no Kenya Standard produced by Kenya Burea u 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 Managing Director.   KENYA STANDARD  DKS 2993 :2023  
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First  Edition  
 
© KEBS 2023  – All rights reserved  iv 
   Raw Walnut Kernels  — Specification   
 
 
Kenya Bureau of Standards, Popo Road, Off Mombasa Road,  
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 kenya bureau of standards (kebs)  
  
KENYA STANDARD  DKS 2993 :2023  
ICS ##.###  
First  Edition  
 
© KEBS 2023  – All rights reserved  v 
  Foreword  
This draft Kenya Standard was prepared by the Edible Nuts and Seeds Technical Committee under the guidance 
of the Standards Projects Committee, and it is in accordance with the procedures of the Kenya Bureau of 
Standards  
Walnut (Juglans regia L.) is considered as a high -quality food with human health benefits because walnut 
kernels are rich in proteins, unsaturated fatty acids, phospholipids, vitamins, minerals, essential fatty acids, and 
other nutrients. Walnuts are most often eaten on their own as a snack but can also be added to salads, pastas, 
breakfast cereals, soups, baked goods, and other different food products.  
This Kenya standard lays down specifications aiming at ensuring the safety and quality of walnut kernels 
produced or traded in and outside the country for human consumption.  
During the preparation of this standard, reference was made to the following document:  
UNECE STANDARD DPP -02 Walnut kernels published by the United Nations, New York, and Geneva,2019.  
Acknowledgement is hereby made for the assistance derived from this source  
 
 KENYA STANDARD  DKS  2993 : 2023  
 
© KEBS yyyy – All rights reserved  1 
  Raw Walnut Kernels  — Specification  
1 Scope  
This Draft Kenya Standard specifies requirements, methods of sampling and test for raw  walnut kernels  obtained 
from walnut tree  (Juglans regia L intended for human consumption.   
2 Normative references  
CXS 193, General standard for contaminants and toxins in food and feed  
KS EAS 39, Hygiene in the food and drink manufacturing industry — Code of practice  
KS EAS 803, Nutrition labelling — Requirements  
KS EAS 804, Claims on foods — General requirements.  
KS ISO 665, Oilseeds — Determination of moisture and volatile matter content  
KS ISO 729, Oilseeds — Determination of acidity of oils  
KS ISO 6579 -1, Microbiology of the food chain — Horizontal method for the detection, enumeration and  
serotyping of Salmonella — Part 1: Detection of Salmonella spp.  
KS ISO 6888 -1, Microbiology of the food chain — Horizontal method for the enumeration of coagulase -positive  
Staphylococci (Staphylococcus aureus and other species) — Part 1: Method using Baird -Parker agar medium  
KS ISO 16050, Foodstuffs — Determination of aflatoxin B1, and the total content of aflatoxins B1, B2, G1 and G2 
in cereals, nuts and derived products — High-performance liquid chromatographic method  
KS ISO 16649 -2, Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of  
beta-glucuronidase -positive Escherichia coli — Part 2: Colony -count technique at 44 degrees C using 5 - 
bromo -4-chloro -3-indolyl beta -D-glucuronide  
KS ISO 21294, Oilseeds — Manual or automatic discontinuous sampling  
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply.  
3.1 
Walnut  
edible nuts obtained from varieties of the species Juglans regia  DKS  2993 :2023  
© KEBS yyyy – All rights reserved  2 
 3.2  
Raw walnut  kernels  
raw walnuts  with their shells removed and which have not been subjected to roasting and/or various forms  
of chemical treatment  
3.3 
damage/defects  
kernel, which is damaged mechanically, or by mould or insects or those showing internal discoloration of 
kernels materially affecting the quality’  
3.4 
other defects  
walnut  kernel that ha s skin discolouration, flesh discolouration and/or sprouted kernels  
3.5 
whole  
walnut  kernel which is not split or broken  
3.6 
split 
separated 'half' of a walnut  kernel  
3.7 
broken  
more than one fourth of the walnut  kernel is broken off  
3.8 
foreign matter  
Any visible and/or apparent matter or material not usually associated with raw and roasted hazelnut kernels.  
 
4 Requirements  
4.1 General requirements  
Raw walnut kernels shall be;  DKS  2993 :2023  
© KEBS yyyy – All rights reserved  3 
 4.1.1, clean, matured, and dry.  
 
4.1.2 free from rancidity, mould, foreign smell and/or  undesirable  taste  and flavour   
 
4.1.3  free from foreign matter  including  insects, insect fragments and mites  
 
4.2 Specific requirements  
4.2.1  Raw walnut kernels shall comply with specific requirements given in Table 1 when tested in accordance 
with the methods specified therein.  
 
 Table 1 — Specific requirements for raw walnut  kernels  
S/N Characteristic  Requirement  Test Method  
1. Moisture  
content, %, m/m,  
max.  Raw Kernels  
5.0 
 
 KS ISO 665  
2. Free fatty acids, %, m/m,  
max.  2 KS ISO 729  
 
 
5 Contaminants  
6.1 Aflatoxin  
Aflatoxin levels in walnut kernels shall not exceed the limits given in Table 3 when tested in accordance with the 
test methods specified therein.  
 
                 Table 3 — Aflatoxin limits for  walnut  kernels  
S/No.  Aflatoxin  Maximum Limit  Test Method  
i)  Total Aflatoxin  
µg/kg  10  
KS ISO 16050  
ii)  Aflatoxin B1  µg/kg  5 
 DKS  2993 :2023  
© KEBS yyyy – All rights reserved  4 
 6.2 Pesticide residues  
Raw w alnut  kernels shall comply with those maximum residue limits established by the Codex Alimentarius 
Commission.  
 
6.3 Other contaminants  
Raw w alnut  kernels shall comply with those maximum limits for other contaminants established in CXS 193.  
7 Hygiene  
7.1 Raw Walnut  kernels shall be produced, prepared,  and handled in accordance with KS EAS 39.  
 
7.2 Raw walnut  kernels shall comply with the microbiological requirements given in Table 4 when tested in 
accordance with the test methods specified therein.  
S/No.  Characteristic  Requirement  Test Method  
i)  Escherichia coli, 
CFU/g A  Absent   
KS ISO 16649 -2 
ii)  Salmonella spp. in 
25 g Absent  KS ISO 6579 -1 
iii)  Staphylococcus 
aureus,CFU/g  Absent  KS ISO 6888  
 
 
8 Packaging  
Raw w alnut  kernels shall be packaged in food grade packaging material that will safeguard the hygienic,  
nutritional, technological,  and organoleptic qualities of the product.  
9 Labelling  
9.1 General  
In addition to the requirements given in KS EAS 38, the product shall be legibly and indelibly labelled with the  
following information:  DKS  2993 :2023  
© KEBS yyyy – All rights reserved  5 
 a) name of the product as “Raw walnut s” and  
 b) where grading is applied, it shall be in accordance to Annex A of this standard.  
9.2 Nutrition labelling and health claims  
Nutrition labelling and health claims shall comply with the requirements given in KS EAS 803, KS EAS 804, and 
KS EAS 805. 
10 Sampling  
Sampling shall be done in accordance with KS ISO 21294DKS 2993: 2023    
 
© KEBS yyyy– All rights reserved   
 Annex A  
(Normative)  
Grading requirements for raw walnut kernels  
 
 Tolerances allowed  
(per cent of defective raw walnut kernels by weight)  
Defects allowed  Extra  Class  I Class II  
Tolerances for produce 
not satisfying the 
minimum  requirements 
of which no more than:  4 6 8 
Mouldy  0.5 1 2 
Rancid or foreign smell 
or taste  1 1 2 
Rotten or deterioration  0.5 1 2 
Damaged by pests  1 1 2 
Living pests  0 0 0 
(b) Tolerances for other defects  
Foreign matter, shell 
fragments,  0.5 1 1 
(c) Tolerances for colour        
Walnut kernels that do 
not belong  to the same 
colour classification  15 15 15 
 
 
 
  
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