TBS/ AFDC 22 (5271) P 3 
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DRAFT  TANZANIA STANDARD  
 
Hatching  egg s – Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS  
                                             
                                                                                                                                      
 
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 Hatching  eggs  – Specification  
                        
 
0   FOREWORD   
 
This Tanzania s tandard was developed due  to rapid increase in demand of eggs in Tanzania 
market. The  standard is intended to control safety and quality  of eggs produced and  traded in 
the country  for hatching .  
 
In the preparation of this  Tanzania standard considerable assistance was drawn from TAS 
6702:2010  Hen egg published  by the Thai Agricultural  Standard.  
 
In reporting, the results of a test or analysis made in accordance with this standard, if the final 
value observed or calculated, is to be rounded off, it shall be  done in accordance with TZS 4 
(see clause 2).  
 
1.0 SCOPE  
 
This Tanzania  standard specifies requirements, methods of sampling and test for  
hatching eggs from chicken .  
2.0 REFERENCES  
For the purpose of this draft Tanzania  standard, the following references sh all apply. 
For dated references, only the edition cited applies. For undated references, the latest 
edition of the referenced document (including any amendments) applies:  
 
TZS 4  Rounding off numerical values . 
TZS 34 -1 Animal feeds and feeding stuffs – Samp ling and test methods – Part 1: General  
TZS 122 Microbiology of food and animal feeding stuffs – Horizontal method for the detection of 
Salmonella spp.  
TZS 538 Packaging and labelling of foods.  
CAC/RCP 15 Code of hygienic pra ctice for eggs and egg products . 
CAC/RCP 1 General Principles of Food Hyg iene.  
Codex Stan 193 Codex General Standard for Contaminants and Toxins in Food and F eed. 
 
3.0 TERMS AND DEFINITIONS  
For the purpose of this standard, the following terms and definitions shall apply:  
 
3.1 hatching  egg 
a fertilized  egg produced by a layer hen intended for hatching .  
 
3.2 egg yolk  
an inner composition of the egg, round, natural colour and floating in the middle of the egg 
white.  
 
3.3 egg white  
an inner composition of the egg consist ing of both the pa rt of firm and viscous liquid surrounding 
the egg yolk and the part of clear and transparent liquid which surrounds the inner firm white.  
                                                                                                                                      
 
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 3.4 egg  grading  
the grouping of egg s into lots having similar characteristics as to colour, weight size and quality.   
3.5 check  
an individual egg which has a damaged outer shell such as broken or cracked shell but its shell 
membranes are intact with no leakage of its content.  
  
3.6 fresh  egg 
an egg considered fresh when the egg yolk is still intact and the white is st ill firm.  
3.7 good egg  
an egg whose shell is unbroken.  
3.8 air cell  
an air space in the large end of an egg between the outer and the inner shell membranes.  
 
3.9 egg candling  
an initial inspection of the egg shell and its interior quality through visual l ight. 
 
4.0 REQUIREMENTS   
 
4.1 General requirements  
The quality of egg  shall be determined by its  exterior and interior quality.  
 
4.1.1 Exterior quality : 
a) Oval shape with one large end and a taper end ; 
b) The shell colour shall be of the breed characteristic, clean and  smooth surface.  
c) The shell shall not be broken or cracked ; 
d) Free of visible mold . 
 
4.1.2 Interior quality  
a) Air cell shall be small, the height not more than 0.8 cm and it does not move when the 
egg is twirled . 
b) For the broken -out egg, the yolk shall not attac h to the inner shell. It shall be firm and 
surrounded by the thick egg white.  
c) The egg shall not be spoiled and free from abnormal odour.  
d) The yolk shall have normal and consistent colour. The egg white shall not be cloudy.  
e) Free of visible mold  
 
4.2 Specific req uirements  
4.2.1  Hatching e ggs shall be grouped into three classes namely Grade AA, A and B  as 
prescribed in Table 1.   
 
 
 
 
 
 
 
 
                                                                                                                                      
 
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 Table 1: Grading of the hatching eggs  
Items  Requirements  
Grade AA  Grade A  Grade B  
1.Shell  
-Outer shell  -Free from 
check  
- Clean, wi thout 
stain  
- Smooth 
surface, free 
from ridges or 
rough areas  The same as grade AA.  - Free from check  
-Clean or may have slightly 
stained area.  
-Total scattered stains shall 
not be more than 1/16 of the 
shell surface. Localized stain 
shall be found less than 1/32 
of the shell surface and it 
shall be loosely attached.  
-The shell surface may have 
ridges or rough areas.  
2. Candling  
2.1 Shell   
-Clean and free 
from inner 
cracks   
The same as grade AA.   
Free from inner cracks  
2.2 Air cell  It shall be in the 
large end of 
egg, the height 
not more  than 
0.3 cm and it 
does not move 
following the 
twirl. It shall be in the l arge end of 
egg, the height not more 
than 0.5 cm and it does not 
move following the twirl.  It shall be in the large end of 
egg, the height not mo re 
than 0.8 cm and it does not 
move following the twirl.  
2.3 Egg white  Blood spots or 
meat spots are 
not present  Blood spots or meat spots 
are not present  Blood spots or meat spots 
may be present. *  
2.4 Egg Yolk  The yolk outline 
is slightly 
defined and 
floats in the 
middle of the 
egg. Blood 
spots or meat 
spots are not 
present.  The yolk outline is fairly well 
defined and approaches the 
shell more closely. Blood 
spots or meat spots are not 
present  The yolk outline is plainly 
visible and approaches the 
shell closely. Blood spots or 
meat spots may be present. *  
3. Broken -out 
egg 
 
3.1 Egg yolk  It is round and  
of bulging  
shape located 
in the middle of 
the thick egg 
white. Blood 
spots or meat 
spots are not 
present.  It is round and of bulging 
shape. Blood spots o r meat 
spots are not present.  The yolk is flattened. Blood 
spots and meat spots may 
be present. *  
3.2 Egg white  The thick white  
liquid  is firm 
and round. The The same as grade AA. The 
thick white is reasonably 
firm. The thick egg white and the 
thin egg white are not firm, 
being weak and watery,                                                                                                                                      
 
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 thin white is not 
enlarged. Blood 
spots or meat 
spots are not 
present  enlarged and watery, 
enlarged and flattened. 
Blood spots and meat spots 
may be present. *  
 
Note:  * The aggregating blood spots and meat spots, w hich may be present and shall not be 
more than 0.3 cm in diameter.  
 
4.2.2 Sizing  
The size of egg shall be considered by weight of an individual egg ( see Table 2). Unless 
otherwise specified , for commercial purposes  the size of eggs shall be as follows:  
 
Table 2: Size of egg s based on weight  
S/N. Size Minimum weight (g ) 
1.  Jumbo  70 and above  
 
2.  Extra Large  65 – 70 
 
3.  Large  60 – 65 
 
4.  Medium  55 – 60 
 
5.  Small  50 – 55 
 
6.  Pullet  45 – 50 
 
 
4.3 Tolerances  
Tolerances for each package shall be as follows:  
 
a) Quality tole rances  
i. For grade AA, the minimum number of grade AA shall be 85%. Grade A can be 
included but not more than 15% of the total number of eggs.  
ii. For grade A, the minimum number of grade A shall be 85%. Grade B can be 
included but not more than 15% of the total  number of eggs.  
iii. For grade B, only the eggs conforming to the requirement for eggs of grade B are 
allowed.  
 
b) Size tolerances  
Eggs of all sizes may include the immediate smaller size not more than 3.4% of the total 
number of eggs.  
 
c) Eggs of all grades and siz es shall be free from check except for the one caused by 
transportation but shall not be more than 5% of the total number of eggs.  
 
 
 
                                                                                                                                      
 
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 5.0 CONTAMINANTS  
Hatching eggs  shall comply with the requirements for maximum limits for contaminants and 
Toxins in Food and Feed as established in Codex Stan 193 and the maximum residue limits for 
pesticides and veterinary drugs established in the respective CAC/MRL 2.  
 
6.0 HYGIENE  
6.1 Hatching eggs shall be produced and prepared under strict hygienic conditions 
according to CAC/RC P 15 – 1976  and CAC/RCP 1 (see clause 2).  
6.2 On testing , samples for hatching eggs shall not contain  Salmonella  in 25 g of 
sample  according to  TZS 122. 
 
7.0 SAMPLING AND TESTS  
 
7.1 Sampling  
Sampling for hatching eggs shall be in   accordance with TZS 34 -1 and test samples 
shall be prepared in accordance with TZS 821  (see clause 2).  
 
7.2 Tests  
Testing of this product shall be done according to test methods prescribed in Table s 1, 
3, 4 and 5  in this standard . 
  
8.0 PACKAGING , MARKING  AND LABELLING  
 
8.1 Packaging  
8.1.1 Chicken eggs  for sale shall be packed in cartons or suitable containers that will avoid 
causing any external or internal damage to the produce. The container shall be clean and 
not previously used.  
 
8.1.2  Chicken eggs shall be packed either in carton or in cases  with their tapered ends 
facing down.  
 
8.1.3 Carton/Plastic  – The packaging material shall be new, standard plastic tray or paper 
cartons molded to suit the size of grade, each holding 6, 12 or 30 eggs.  
 
8.1.4 Cases  – Chicken eggs consisting of thirty dozen or more packed in wooden or 
fiberboard boxes.  
 
8.2 Marking and l abelling  
Each container shall delibly and indelibly be marked to display the following information:  
 
a) Breed and  grade of hatching eggs ; 
b) Date of production;  
c) Date of expiry;  
d) Number of eg gs in a package or its net weight in g or kg ; 
e) Name and address of producer, importer and distributor;  
f) Instruction for storage and transportation. The packages shall be labeled as 
“fragile”.                                                                                                                                       
 
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 g) The language on the label shall be “Kiswahili” or Kiswahili and En glish. 
Additional language  may be used depending on the designated market.  
 
8.3 The container may also be marked with TBS Certification Mark.  
NOTE  – The TBS Standards Mark of Quality may be used by the manufacturers only 
under license  from TBS. Particulars  of conditions under which the licenses  are 
granted may be obtained from TBS.