NORTHERN CORRIDOR STANDARD   NC 4:2018   
 
 
 
 
 
 
 
 
 
 
 
 
Roasted Macadamia ─ Specification 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 NC 4:2018  
  
 
Roasted macadamia — Specification 
 
 
 
 
1 Scope  
 
 
This Northern corridor  Standard specifies the requirements, methods of  sampling and testing for roasted 
macadamia of varieties  (cultivars) grown from Macadamia integrifolia, Macadamia tetraphylla and 
Macadamia ternifolia , and their hybrids intended for direct consumption 
 
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. 
 
CODEX STAN 192, general standard  for food additives  
EAS 35, Edible salt — Specification  
EAS 38, Labeling of prepackaged foods — Specification  
EAS 39, Hygiene in the food and drink manufacturing industry — Code of practice  
ISO 542:1990, Oilseeds -- Sampling  
ISO 735, Oilseed residues -- Determination of ash insoluble in hydrochloric acid  
ISO 12193, Animal and vegetable fats and oils -- Determination of lead by direct graphite furnace atomic 
absorption spectroscopy  
ISO 15774, Animal and vegetable fats and oils — Determination of cadmium con tent by direct graphite 
furnace atomic absorption spectrometry  
ISO 17239, Fruits, vegetables and derived products -- Determination of arsenic content -- Method using 
hydride generation atomic absorption spectrometry  
ISO 7251, Microbiology of food and anima l feeding stuffs -- Horizontal method for the detection and 
enumeration of presumptive Escherichia coli -- Most probable number technique  
ISO 6579, Microbiology of food and animal feeding stuffs — Horizontal method for the detection of 
Salmonella spp. 
ISO 16050 , Foodstuffs — Determination of aflatoxin B 1, and the total content of aflatoxins B 1, B2, G 1 and G 2 
in cereals, nuts and derived products — High-performance liquid chromatographic method  
ISO 27107 , Animal and vegetable fats and oils — Determination of peroxide value — Potentiometric end -
point determination  
 
3 Terms and d efinitions 
 
 
For the purpose of this standard, the terms and definition in the standard for macadamia kernels and the following 
terms and definitions shall apply: 
 
  NC 4:2018  
  
 
3.1 
 
roasted macada mia 
 
kernels which have been subjected to heat by dry or wet roasting and to which salt or other food ingredients  may 
have been added 
 
 
4  Requirements  
 
4.1 General requirements  
 
Roasted Macadamia shall have characteristic colour and be free from off -flavour  
 
4.2 Macademia Kernels  
Macadamia kernels for roasting shall conform to the standard for Macadamia kernels  
4.3  Specific q uality  requirements  
 
Roasted Macadamia shall comply with the requirements stipulated in Table 1. 
 
 
Table 1 — Limits for Roasted macada mia 
 
Characteristic limit
s Test method 
Moisture content, % m/m, max. 1.5 ISO 1026  
Acid insoluble ash (roasted and salted), % m/m, max. 0.5 ISO 735  
Peroxide value, max. , meq/kg 3  ISO 3960  
 
4.4 Grading 
 
Roasted Macadamia may be  graded. When graded the macadamia shall conform to the grades in Table 2. 
 
 
Table 2 — Grades  for Roasted Macadamia 
 
S/N Grade Description Whole kernel 
percentage Size range 
(m/m) 
i
) Premium Whole kernels 100 25 to 15 
ii
) Popular Wholes and halves min. 50  17 to 10 
iii
) Cocktail Wholes and halves 11 to 49  17 to 10 
iv
) Medium Halves and pieces Max. 10  12 to 4 
v
) Chips Pieces and bits None  5 to 0.5 
a.         Tolerance — Up to 5 %  by mass of the next lower grade. 
 
5 Food additives 
 
 
Roasted Macadamia may be preserved by using food additives complying with CODEX STAN 192. 
 
 
6 Contaminants 
 
 
6.1 Pesticide residues 
 NC 4:2018  
  
Roasted Macadamia shall conform to those maximum residue limits for pesticide residues established by 
Codex Alimentarius Commission for this commodity. 
 
 
6.2  Heavy metals 
 
 
Roasted macadamia shall be free from heavy metals in amounts which may represent a hazard to health. 
Heavy metal contaminants, if present, shall not exceed the limits stipulated in Table 3. 
 
Table 3 — Heavy metal contaminant  limits 
 
SL No. Parameter Maximum Limits Test method 
i) Arsenic (As), ppm, 0.1 ISO 17239  
iii) Lead (Pb), ppm, 0.10 ISO 12193  
iv) Cadmium (Cd), ppm, 0.02 ISO 15774  
 
6.3 Aflatoxin  
Roasted macadamia kernels shall conform to tho se maximum limits for aflatoxin  stated in Table 4  
Table 4 - Limits  for aflatoxin  in roasted macadamia kernels  
SN Aflatoxin type  Limits, µg/kg, max.  Methods of test  
1 Aflatoxi n B 1 5 ISO 16050  
2 Total Aflatoxins  10 
 
 
7 Hygiene  
 
 
Roasted Macadamia shall be handled in hygienic manner in accordance with EAS 39 . Roasted Macadamia 
shall conform  to the microbiological limits in Table 5 
 
 
Table 5 — Microbiological limits for Roasted Macadamia 
SL 
No. Micro -organism  Maximum limits  Test method  
i) Escherichia coli,  cfu/g  Absent  ISO 7251  
ii) Salmonellae,  in 25g Absent   ISO 6579   
 
 
 
9 Packaging  
 
9.1 Roasted Macadamia may be sold packaged or loose. Packaged macadamia kernels shall be packaged 
in such a way to protect the produce from mechanical, heat and frost damage. Macadamia kernels shall be 
packaged in food grade materials that will safeguard the hygienic, nutritional, technological and organoleptic 
qualities of the produce. 
  NC 4:2018  
  
9.2 The packaging materials shall conform to the environmental legislation of the destination country. 
 
 
10 Weights and measures  
 
 
The weight of the package of the product shall comply with Weights and Measures regulations of the 
importing Partner State.  
 
 
11 Labelling  
 
11.1 In addition to the requirements of  EAS 38 , the following specific requirements shall apply and shall be 
legibly and indelibly marked: 
a) name of the product shall be “Roasted Macadamia  
 
b) name of the product shall be “Roasted Macadamia” ;  
c) name and location address of the exporter and/or packer shall be declar ed; 
d) country of origin; 
e) Net weight; 
f) lot identification (batch number); 
g) declar ation of ingredients , if used; 
 
h) expir y date; 
i) grade; and 
j) storage instruct ions. 
 
12 Sampling  
 
Sampling shall be done in accordance to ISO 542. 
 
 NC 4:2018  
  
 
 
Annex A 
(normative) 
 
Determination of moisture content 
 
 
 
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 a nd weigh with the lid on. Repeat the process of heating, cooling and weighing at half- 
hour intervals until the loss in weight between two successive weighings is less than 1 mg. Record the lowest 
weight obtained. 
 
 
A.1.2    Calculation and expression of results, moisture % by mass 
 
  m1  m2 x 100 
m1  m3 
 
where: 
 
 
m1: is the mass in g of the dish and sample before drying; 
m2: is the mass in g of the dish and sample after drying; and 
m3: is the mass in g of the dish only.  NC 4:2018  
  
 
 
Annex B 
(normative) 
 
Determination of oil content 
 
 
 
B.1  Reagents 
 
 
B.1.1    Petroleum ether of boiling range of 40 0C to 60 0C. 
 
 
B.1.2    Hezane of food grade. 
 
 
B.2  Procedure 
 
 
Weigh accurately about 2.5 g of the sample, dried as described under A1.1, and extract with petroleum ether 
or hexane, food grade, in a Soxhlet or other suitable extractor. The extraction period may vary from 4h 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 weighings is less than 1 mg. 
 
 
Note the lowest mass. 
 
 
B.3  Calculation and expression of results 
 
 
Crude fat (on moisture-free basis), % by mass 
 
m   m  
 100         1           2   
m3 
 
where, 
 
 
m1: is the mass in g of the extraction flask with dried extract; 
 
m2: is the mass in g of extraction flask; and 
 
m3: is the mass in g of the dried sample for the test. NC 4:2018  
  
 
 
Annex C 
(normative) 
 
Determination of free fatty acid 
 
 
 
C.1  Apparatus 
 
 
Soxhlet fat extraction apparatus. 
 
 
C.2  Reagents 
 
 
C.2.1    Petroleum, ether,  distilling below 65 0C, or ethylether. 
 
 
C.2.2    Alcohol potassium hydroxide, 0.1N  (use absolute or alcohol denatured with MeOH). 
 
 
C2.3     Alcohol-ether mixture, equal volumes of 96 % alcohol and ethyl ether. 
 
 
C.2.4    Phenolphathalein solution, one % in alcohol ether and add alcoholic KOH solution to a faint pink. 
 
 
C.3  Procedure 
 
 
C.3.1    Extract 10.00 ± 0.01 g of the sample taken in a thimble with petroleum ether  for about 16 h in a 
Soxhlet extraction apparatus. Completely evaporate the solvent from extraction flask (weighed previously) on 
a steam bath, cool and weigh the Soxhlet flask with the residue and  from the difference of the mass of fat 
obtained from the material. Dissolve the residue in the extraction flask with 50 ml  of the alcohol-ether 
phenolphthalein solution. Titrate the dissolved extract, with standard potassium hydroxide solution to a faint 
pink colour which persists for 10s. If emulsion is formed during titration, dispel by adding second 50 ml portion 
of the alcohol-ether phenolphthalein solution. 
 
 
C.3.2    Make a blank titration on 50 ml of the alcohol-ether phenolphthalein solution and subtract this value 
from the titration value of the sample. If the additional 50 ml portion of the alcohol-ether phenolphthalein 
solution is added, double the blank titration.  10
10  
  
Annex D 
(normative) 
 
Determination of salt 
 
 
 
D.1  Reagents 
 
 
D.1.1    Acetone. 
 
 
D.1.2    10 % calcium acetate solution. 
 
 
D.1.3    HNO3. 
 
 
D.1.4    0,1 N AgNO3. 
D.1.5    FeAlum indicator. 
D.1.6    0.1 N NH 4SCN. 
D.2  Procedure 
D.2.1    Weight 2 g of thoroughly mixed sample into a platinum or silica dish. 
 
 
D.2.2    Disperse sample with 10 ml of acetone. 
 
 
D.2.3    Remove acetone at room temperature, with air current. 
D.2.4    Add, and thoroughly mix, 10 ml of 10 % calcium acetate. 
D.2.5    Carefully dry on a steam bath. 
D.2.6    Ash in a muffle oven at 550 0C (10220F) (complete ashing is not necessary). 
 
 
D.2.7    Place ash in a beaker and dissolve ash in 25 ml HNO3 (1 + 3). 
 
 
D.2.8 Add at least 2 - 4 ml of 0.1 N AgNO3 that is just enough to precipitate all chloride present. 
 
 
D.2.9    Add at least 5 ml of 0.1 N AgNO3 in excess, to 8. 
 
 
D.2.10 Heat  to boil, cool, then add 5 ml FeAlum indicator. 
 
 
D.2.11  Titrate excess Ag with 0.1 N NH4SCN (which has been standardized to equalize nomalities) to a 
permanent light brown end point. 11
11  
  
 
 
D2.12   Subtract the amount of NH4 SCN used (D.2.11) from the total AgNO 3  used in D.2.8 and D.2.9. The 
resulting difference is the ml of 0.1 N AgNO3 used in the calculation of salt (D.2.13). 
 
 
D.2.13  Calculate as % NaCl 
 
mL  of  0.1N AgNO 3 0.058 45) 100 
