Reference number  
DRS 170:2018  
© RSB 2018  
 
 
 RWANDA 
STANDARD  DRS 
170 
 
Second edition  
2018 -mm-dd 
 
Macadamia kernels  — Specification  
  DRS 170:2018  
©RSB 2018 - All rights reserved                  ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
© RSB 2018  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reprodu ce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rs b.gov.rw   
ePortal: www.portal.rsb.gov.rw   DRS 170:2018  
iii                ©RSB  2018  - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Requirements  ................................ ................................ ................................ ................................ .........  3 
4.1 Classification  ................................ ................................ ................................ ................................ .........  3 
4.2 General requirements  ................................ ................................ ................................ ...........................  3 
4.3 Specific requirements  ................................ ................................ ................................ ...........................  4 
5 Contaminants  ................................ ................................ ................................ ................................ .........  4 
5.1 Pesticide residues  ................................ ................................ ................................ ................................ . 4 
5.2 Heavy metals  ................................ ................................ ................................ ................................ ..........  4 
6 Mycotoxin limits  ................................ ................................ ................................ ................................ .... 4 
7 Hygiene  ................................ ................................ ................................ ................................ ...................  4 
8 Packaging  ................................ ................................ ................................ ................................ ...............  5 
9 Weights and measures  ................................ ................................ ................................ .........................  5 
10 Labelling  ................................ ................................ ................................ ................................ .................  5 
11 Sampling  ................................ ................................ ................................ ................................ ................  5 
Annex  A (normative)  Determination of moisture content in macadamia kernels ................................ ....... 6 
A.1 Procedure  ................................ ................................ ................................ ................................ ...............  6 
Annex  B (normative)  Determination of oil content  ................................ ................................ ........................  7 
B.1 Reagents  ................................ ................................ ................................ ................................ ................  7 
B.2 Procedure  ................................ ................................ ................................ ................................ ...............  7 
B.3 Calculation and expression of results  ................................ ................................ ................................  7 
Annex  C (informative)  Provisions concerning sizing  ................................ ................................ ....................  8 
C.1 Sizing  ................................ ................................ ................................ ................................ ......................  8 
C.2 Presentation  ................................ ................................ ................................ ................................ ...........  9 
 DRS 170:2018  
©RSB 2018 - All rights reserved                  iv 
 Foreword   
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards 
adop ted by Technical committ ees are ratified  by me mbers of RSB Board of Director s for publication and 
gazettment as Rwanda Standards.  
DRS 170 was prepared by Technical Committee RSB/TC 016, Fresh fruits and vegetables . 
In the preparation of this standard, reference was made to the following standard  (s): 
1) KS 868: 2009 - Macadamia kernels — Specification  
The assistance de rived from the above source is hereby acknowledged with thanks.  
This second edition cancels and replaces the first edition (RS  170:2012 ), which  has been technically revised.  
Committee membership  
The following organizations were represented on the Technical Committee on Fresh fruits and vegetables  
(RSB/TC 016) in the  preparation of this standard.  
Enterprise Urwibutso  
FRESHCO  
National Agricult ural Export Development Board  (NAEB)  
NORELGA Macadamia  
PEBEC Ltd  
Rwanda Nuts Company  
SORWATOM  
Rwanda  Standards Board  (RSB) – Secretariat  DRS 170:2018  
1                ©RSB  2018  - All rights reserved  
 Macadamia kernels  — Specification  
1 Scope  
This Draft Rwanda Standard specifies the requirements , sampling and test methods for macadamia kernels of 
varieties (cultivars) grown from Macadamia integrifolia, Macadamia tetraphylla, M acadamia ternifolia and their 
hybrids . 
This standard does not apply to macadamia kernels that are processed by salting, sugaring, flavouring or 
roasting  or for industrial processing  of macadamia product other than food . 
2 Normative references  
The following documents are referred to in the text in such a way that some or all of  their content constitutes 
requirements 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.  
AOAC 999.10,  Lead, Cadmium, Copper, Iron, and Zinc in foods, Atomic Absorption Spectrophotometry after 
microwave digestion  
RS CAC/RCP1, Code of Practice  — General Principle for food Hygiene  
RS EAS 38, Labelling  of pre -packaged foods  
RS 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  
RS 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  
RS ISO 4833 -1, Microbiology of the foo d chain -- Horizontal method for the enumeration of microorganisms -- 
Part 1: Colony count at 30 degrees C by the pour plate technique  
RS ISO 6579 -1, Microbiology of the food chain -- Horizontal method for the detection, enumeration and 
serotyping of Salmo nella -- Part 1: Detection of Salmonella spp . 
3 Terms and definitions  
For the purposes of this standard, the follow ing terms and definitions apply.   
©RSB 2018 - All rights reserved                  2 
 3.1 
macadamia kernel  
shelled or decorticated and/or dry macadamia  
3.2 
whole kernel  
kernel which has not lost  more than ¼ of it 
3.3 
half kernel  
Approximately half of a whole kernel, with not more than 1/8 of its mass chipped off or missing  
3.4 
piece  
kernel which is less than half a kernel  
3.5 
extraneous matter  
inorganic  and organic  matter  other than macadamia kernels   
3.6 
defective kernels  
defective kernels mean any or all of the following:  
a) kernels with adherings of extraneous matter;  
b) insect damaged kernels;  
c) diseased  kernels  (rotten, decayed or mould kernels) ; 
d) rancid kernels;  
e) immature kern els; 
f) heat damaged kernels;  
g) weather -damaged kernels.  DRS 170:2018  
3                ©RSB  2018  - All rights reserved  
 4 Requirements  
4.1 Classification  
In accordance with the defects allowed, macadamia kernels shall be  classified into the following classes  as 
specified in Table 1: 
a) Class I; and  
b) Class II.  
Table 1 — Specific requirements for each class  
Defects allowed  Tolerances allowed  
(percentage of defective kernels, number by number or 
mass by mass ) Test method  
Class I  Class II  
   
 
 
 
 
EAS 901 Clause 4  Not sufficiently developed, 
shrunken and shrivelled  3 5 
Mouldy  Absent  Absent  
Rancid or damaged by 
pests, rotting or 
deterioration  1.5 2 
Off-odour or off -flavour by 
any cause   Absent  Absent  
(b) Size tolerances   
-For produce not conforming 
to the size indicated, if sized  7 7 
(c) Tolerances for other 
defects   
Macadamia kernels 
belonging to other 
varieties/types than those 
indicated on the package  10 10 
[Foreign matter, loose 
shells, shell fragments, 
fragments of hull, particles 
of the shell, dust (by weight)  Absent  Absent  
4.2 General requirements  
Macadamia kernel shall:  
a) have characteristic colour ; 
b) have the characteristic flavour of the fresh macadamia kernels ;  
©RSB 2018 - All rights reserved                  4 
 c) be free from surface oil and dust ; and  
d) be free from live insects, insect fragments and mites ; 
4.3 Specific  requirements  
Macadamia  kernels shall comply with the requirements stipulated in Table 2 when tested in accordance with 
test methods specified therein . 
Table 2 — Specific r equirements limits for macadamia kernels  
S/N Characteristic  Limits  Test method  
i.  Moisture content, % , m/m, max.  2.0 Annex A 
ii.  Oil content on dry weight basis, % , m/m, min.  70 Annex B 
5 Contaminants  
5.1 Pesticide residues  
Macadamia kernels shall conform to those maximum residue limits for pesticide residues established by 
Codex Alimentarius Commission for this commodity.  
5.2 Heavy metals  
Macad amia kernels  shall not contain heavy metals in amounts which can represent a hazard to human health 
and shall comply with the limits in Table 3. when tested in accordance with test methods specified therein.  
Table 3 —Heavy  metals contaminant limits  
S/N  Heavy metal  Maximum limit  
mg/kg  Test method  
i.  Lead (Pb),  0.10 AOAC 999.10  
ii.  Cadmium (Cd),   0.02 
6 Mycotoxin limits  
Total aflatoxin levels in macadamia kernels for human consumption shall not exceed 10 µg/kg and aflatoxin  
B1 shall not exceed 5 µg/kg when tested in accordance with ISO 16050.  
7 Hygiene  
7.1 Macadamia kernels shall be handled in hygienic manner in accordance with RS CAC/RCP  1. 
7.2 Macadamia kernels shall comply with the microbi ological limits given in Table 4  when tested in 
accordance with test methods specified therein.  DRS 170:2018  
5                ©RSB  2018  - All rights reserved  
 Table 4  — Microbiological limit s for macadamia kernels  
S/N  Microorganisms  Maximum l imit Test Method  
i.  Total plate count, CFU/g  104 RS ISO 4833 -1 
ii.  Escherichia coli,  CFU/g  <1 RS ISO 16649 -2 
iii.  Salmonella spp  in 25g absent  RS ISO 6579 -1 
8 Packaging  
8.1 Macadamia kernels shall be packaged in food grade materials that will safeguard the hygienic, 
nutritional, technological and organoleptic qualities of the produce. They shall be packaged in such a way to 
protect the product from mechanical, heat and frost damage.  
8.2 The packaging materials shall conform to the environmental legislation of the destination country.  
9 Weights and measures  
Macadamia kernels shall be packaged in accordance with  the nation al weights and measurement regulations.  
and environmental requirements in the destination country. be in accordance with.  
10 Labelling  
In addition to the requirements of EAS 38 , the following information shall be legibly and indelibly marked : 
a) name of the produ ce as “Macadamia  kernels”  
b) name and location address of the exporter and/or packer;  
c) country of origin  
d) net weight  
e) lot identification (batch number);  
f) packing date;  
g) expiry date; and 
h) Storage conditions.  
11 Sampling  
Sampling shall be done in accordance with RS ISO 24333.   
©RSB 2018 - All rights reserved                  6 
 Annex  A 
(normative)  
 
Determination of moisture content  in macadamia kernels  
A.1 Procedure  
A.1.1  Weigh accurately about 10 g of the material in a suitable moisture dish previously dried in an electric 
oven and weighed. Place the dish in a vacuum oven at 95 0C to 100 0C under pressure 100 mm/Hg. Cool the 
dish in a desiccator and weigh with the lid on. Repeat the process of heating, cooling and weighing at halfhour 
intervals until the loss in weight between two successive weighings is less than 1 mg. Record the lo west 
weight obtained.  
A.1.2  Calculation and expression of results, moisture % by mass  
100×) (). (
3 12 1
mmmm

 
where,  
1m
 is the mass in g of the dish and sample before drying;  
2m
 is the mass in g of the dish and sample after drying; and  
3m
 is the mass in g of the dish only  
  DRS 170:2018  
7                ©RSB  2018  - All rights reserved  
 Annex  B 
(normative)  
 
Determination of oil content  
B.1 Reagents  
B.1.1  Petroleum ether, of boiling range 40 0C to 60 0C. 
B.1.2  Hexane , food grade.  
B.2 Proc edure  
Weigh accurately about 2.5 g of the sample, dried as described under A.1.1, and extract with petroleum ether 
or hexane, food grade, in a Soxhlet or other suitable extractor. The extraction period may vary from 4 h at a 
condensation rate of 5.6 drops per second. Dry the extract on a steam bath for 30 min ., cool in a desiccator 
and weigh. Continue at 30 min . intervals this alternative drying and weighing until the difference between two 
successive weighing  is less than 1 mg.  
Note the lowest mass.  
B.3 Calculation and expression of results  
Crude fat (on moisture -free basis), % by mass = 
32 1 ) (100mmm
 
where,  
1m
 is the mass in g of the extraction flask with dried extract;  
2m
 is the mass in g of extraction flask; and  
3m
is the mass in g of the dried sample for the test .  
©RSB 2018 - All rights reserved                  8 
 Annex  C 
(informative ) 
 
Provisions concerning sizing  
C.1 Sizing  
C.1.1  Sizing of macadamia kernels is optional. However, when sized, size is determined by the maximum 
diameter of the equatorial section of the whole nut or by widest diameter of the designated style size 
requirements.  
C.1.2  In case style designations  are used; the following provisions apply:  
C.1.2.1  Style 0 - (Wholes) shall consist of not l ess than 98 % whole kernels with the remaining 
percentage consisting of pieces of which not more than 1 % will pass through > 21 mm (1/4 inch) square 
opening.  
C.1.2.2  Style I - (Wholes) shall consist of not less than 95 % whole kernels, with the remaining 
percentage consisting of pieces of which no more than 1 % will pass through between 19 mm to 21 mm (¼ 
inch) square opening.  
C.1.2.3  Style II - (Wholes and halves) shall consist of at least 50 % whole kernels, with the remaining 
percentage consisting of pie ces of which no more than 2 % will pass through a 7.8 -mm (5/16 inch) square 
opening.  
C.1.2.4  Style III - (Cocktail) shall consist of at least 90 % half or larger kernels, included therein at least 15 
% whole kernels, with the remaining percentage consistin g of pieces of which no more than 2 % will pass 
through a 6.25 -mm (¼ inch) opening.  
C.1.2.5  Style IV - (Halves and pieces) shall consist of at least 50 % half kernels, with the remaining 
percentage consisting of pieces with no more than 5 % larger than hal f kernels.  
C.1.2.6  Style V - (Large diced) shall consist of units which are smaller than half kernels but of such size 
that no more than 5 % will pass through a 7.8 -mm x 25 mm ( 5/16-inch x 1 inch) opening, included therein not 
more than 2 % that will pass through a 2.34 -mm (3/32 inch) square opening.  
C.1.2.7  Style VI - (Chips) shall consist of units of such size that at least 95 % will pass through a 7.8 -mm 
x 25 mm ( 5/16-inch x 1 inch) opening but no more than 2 % will pass through a 3/32 -inch square openin g. 
C.1.2.8  Style VII - (Bits and diced) shall consist of units which are smaller than half kernels and of such 
size that at least 95 % will pass through a 7.8 -mm (5/16 inch) square opening but no more than 10 % will pass 
through a 2.34 -mm (3/32 inch) squar e opening.  
C.1.2.9  Style VIII - (Fines) shall consists of broken, chipped or chopped kernels of such size that all units 
will pass through a 6.25 -mm (¼ inch) square opening and most will also pass through a 2.34p -mm (3/32 inch) 
square opening.  DRS 170:2018  
9                ©RSB  2018  - All rights reserved  
 C.2 Presentation  
C.2.1  The contents of each package shall be uniform and contain only macadamia kernels of the same, 
quality, size (if sized) and variety or commercial type (if indicated).  
C.2.2  The visible part of the contents of the package shall be representative of it s entire contents.  
 
 
 
 
 
 DRS 170:2018  
ICS 67.08. 10 
 
 
©RSB 2018  - All right s reserved