AFDC 14 (4776 ) P3 
 
  
              
 
DRAFT TANZANIA STANDARD  
 
UHT milk – Specification  Part 2: Reconstituted /Recombined/Toned milk 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS  
                                                            
 UHT Milk  – Specification  Part 2: Reconstituted /Recombined/Toned milk                                               
 
0   FOREWORD  
 
Ultra -high temperature  processed (UHT) –sterilized  milk is one of the dairy products produced and 
traded in the country  for human consumption . Whereas  raw milk is  the commonly  used  raw 
material, reconstituted, recombined and toned milk are increasingly been used to fill the raw milk 
supply gap ; especially  during the dry season or periods of prolonged droughts . Hence  it has been 
necessary to prepare this sta ndard to make sure that the product s produced from these raw 
materials are of the required safety and quality .  
 
In the preparation of this Tanzania standard assistance was drawn from EAS 27:2007 , UHT Milk  – 
Specification ; published by the East African Com munity.  
 
In reporting,  the results of a test or analysis made in  accordance with this s tandard, 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 p rescribes the requirements, methods of sampling and test for UHT milk  
derived  from reconstituted, recombined or  toned  milk.  
 
2.0 REFERENCE S 
For the purpose of this Tanz ania s tandard, the fo llowing references shall apply. For dated 
references, only the edi tion cited applies. For undated references, the latest edition of the 
referenced standard  (including any amendments) applies:  
 
TZS 4  – Rounding off numerical values . 
TZS 109  – Food  processing units – code of hygiene . 
TZS 112  – Milk – Production, processing , transportation and distribution – code of hygiene.  
TZS 118 – Microbiology of food and animal feeding stuffs – Horizontal method for enumeration of 
microorganisms – Colony count technique at 30 0C. 
TZS 119  – Microbiology – General guidance for the enumera tion of coliforms – Most Probable 
Number technique (MPN).  
TZS 122 – Microbiology of food and animal feeding stuffs – Horizontal method for the detection of 
Salmonella spp.  
TZS 124  - Milk and milk products – sampling for microbiological examination.  
TZS 125  – Microbiology of food and animal feeding stuffs – Horizontal method for the enumeration 
of coagulase -positive staphylococci ( Staphylococcus aureus  and other species) – Part 1: Technique 
using Baird -parker agar medium – Amendment 1: Inclusion of precision  data.  
TZS 131  – Microbiology  - General guidance for enumeration of yeast and moulds – Colony count 
technique at 25  ºC. 
TZS 538  – Labelling of pre -packaged foods — General requirements  
Codex S tan 193  – Codex General Standard for Contaminants and Toxins in Food and Feed 
ISO 6888 – Enumeration of coagulase positive Staphylococcus spp 
 
3.0 TERMS AND DEFINITIONS  
 
For the purpose of this standard , the following terms and definitions shall apply:  
 
 
3.2 milk  
normal, clean and fresh secretions extracted from the ud der of a healthy milking cow, properly fed 
and kept, but excluding that got during the first seven days after calving . Compare with other 
standards   
 3.3 pasteurized milk  
milk which has been efficiently heat treated at a sufficiently high temperature for app ropriate period 
of time to ensure complete destruction of all pathogenic organisms, so as to enable the product to 
be transported, distributed and consumed as liquid milk . 
3.4 homogenization  
process by which milk fat globules are finely divided and intersp ersed to form a homogeneous 
product so as to prevent the fat from floating on the surface and adhering to the inside of the 
container . 
3.5 UHT   
Utra high temperature treatment usually  above 1350C for 1 to 2 seconds; in milk it aims to destroy all 
microorga nisms including spores . 
 
3.5 UHT milk  
milk that has under gone a ultra-high temperature treat ment , homogenized, filled and sealed 
aseptically into sterile retail containers in order to achieve commercial sterility.  
 
3.6 commercial sterility  
attained practi cal sterility after the product has been treated  and aseptically packaged  aiming at long 
shelf life without refrigeration.  
3.7 reconstituted milk  
is a product resulting from the addition of water to the dried or concentrated form of the product in 
the amo unt necessary to re -establish the appropriate water to solids ratio.  
 
3.8 recombined milk  
is a product resulting from the combining of milkfat and milk -solids -non-fat in their preserved forms 
with or without the addition of water to achieve the appropriate  milk product composition.  
 
3.9 toned milk  
is a product prepared by a mixture of raw cow milk with skimmed milk or powdered milk in the 
amount necessary to re -establish the appropriate milk product composition.  
 
4.1 Culinary steam  
 
4.0 REQUIREMENTS  
 
4.1 Genera l requirements   
4.1.1  Raw materials   
a) Cream and cream powder, butter oil, milk powder, skimmed milk powder when used shall 
comply  with specific Tanzania standard.  
b) UHT milk shall not contain added water, preservatives, or any other added substances.  
4.1.2 Process requirements  
The milk shall be subjected to temperatures between 135 °C and 150 °C for 2 to 6 seconds, direct 
or indirect heating sufficient to attain commercial sterility, followed by immediate cooling to ambient 
through temperature and aseptically packag ed in sterile containers.  Allign with the definition  
4.1.3.1  Direct heat  
Where steam injection is used for heating, only culinary steam shall be used, and the compositional 
quality of the milk shall be the same before and after treatment.  
 
4.1.3.2  Holding time before sale  
UHT milk shall be held by the processor at ambient temperatures for at least five days before 
release to the market. When samples are tested organoleptically after this storage, the flavour shall 
be normal, and all signs of spoilage shall be absent.  
 
4.1.4 Shelf life  
UHT milk shall have a minimum shelf life of 90 days at ambient temperature.   
  
4.1.5 UHT milk shall be;  
a) normal in texture and colour.  
b) processed without affecting the composition of the product  
c) free from off -flavours and taints fat.  
 
4.2 Specific re quirements  
UHT milk shall comply with the requirements given in Table 1.  
Table 1: Chemical requirements for UHT milk  
S/no.  Characteristic  Requirement  Method of test  
 pH Put a 
requirement   
1. pH variation on 7 days incubation 
(max.)  0.3 Annex A  
 
 Titrabl e acidity, % lactic acid  Put a 
requirement   
2. Titratable acidity variation on 7 days  
incubation, % lactic acid (max)  0.02 Annex B  
3. Milk fat percentage (m/m)  
(a) Whole milk (min.)  
(b) Fat reduced milk  
(c) Low fat milk  
(d) Skimmed milk, max   
3.25 
2.25 ⎯ 3.24 
1.5 ⎯ 2.24 
0.5  ISO 2446  
4. Milk solids not fat, min  8.5  ISO 2446  
5. Freezing point depression (oC) 525 – 550 ISO 5764  
 Milk density (g/ml) at 20 oC 1.028 – 1. 03 2 Lactometer  
 
5.0 CONTAMINANTS  
5.1 UHT Milk  shall comply with the current maximum limi ts for contaminants in Codex Stan 193 and 
the current maximum residue limits for pesticides and veterinary drugs established in the CAC/MRL 
2.  
 
5.2 Pesticide and veterinary drug residues  
UHT Milk shall comply with the current maximum residue limits for pesticides and veterinary drugs 
established in the CAC/MRL 2.  
 
5.3 Heavy metals  
UHT Milk shall comply with the current maximum residue limits for heavy metals as described in  the 
CAC/MRL 2.  
 
6.0  HYGIENE   
6.1 The product shall be prepared under strictly conditi ons according to TZS 109 and TZS 112 (See 
clause 2).   
 
6.2 The product on testing shall not contain microbiological count more than the  level given in Table  
2. 
 
Table 2: Microbiological requirements  
S/No.  Characteristic  Requirement  Methods of test  
(see c lause 2)  
1. Total plate count per 10 ml 
max.  10   TZS 118 
  
 2. Coliform , cfu/ml   Absent  TZS 119  
 
3. Staphylococcus (coagulase 
positive) , cfu/ml  Absent   TZS 125  
 
 
 
7.0   SAMPLING AND TESTS  
7.1 Sampling  
Sampling of the product covered under this standar d shall be done according to TZS 124 . (see 
clause 2).  
 
7.2 Tests  
Testing of this product shall be done accordin g to test methods prescribed in Table 1  2 and 3.  
 
8.0PACKAGING, MARKING  AND LABELLING  
 
8.1 Packaging  
The milk shall be packaged aseptically int o sterile food grade containers and sealed hermetically.  
 
8.2 Marking and labelling  
In addition to marking and labelling requirements prescribed in TZS 538, UHT milk  containers shall 
be also legibly and indelibly marked with the following:  
 
a) name of the p roduct “ Recombined UHT milk/Toned UHT milk/ Reconstituted UHT milk “ 
b) The date of manufacture  
c) Country of origin  
d) Name and address of manufacturer  
e) Expiry date  
f) Net content in volume  
g) Batch or code number  
h) Nutritional information  
i) Registered trade mark, if any  
j) Instruction for use  
k) Storage condition and hygienic handling of the product.  
l) The language on the label shall be “Kiswahili” or Kiswahili and English. A dditional  language may 
be used depending on the designated market.  
 
8.3 The container may also be marked wit h TBS Certification Mark.  
NOTE – The TBS Standards Mark of Quality may be used by the manufacturers only 
under licence from TBS. Particulars of conditions under which the licenses  are granted 
may be obtained from TBS.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
AnnexA  
(normative)  
 
Determination of pH variation  
A.1 Apparatus  
A.1.1  Incubator adjusted at 55 °C ± 1 °C  
A.1.2  pH meter  
A.2 Procedure  
A.2.1  Determine the pH of 50 ml of the sample in the flask, with a glass electrode at 20 °C and 
note reading. Then incubate another 50 ml of th e sample at 55 ± 1 °C for seven days. Examine the 
flask each day, then shake and replace it in the incubator. If any physical alteration of the contents 
is observed (coagulation with, or without exudation, grittiness, flocculation, formation of bubbles or 
scum peptonization or proteolysis) the result of the test shall be considered positive and the sample 
as nonsterile.  
A.2.2  If no alteration takes place during the five days incubation at 55 ± 1 °C remove the sample 
from the incubator and cool to room tempe rature. Take a small portion of it and measure the pH in 
the pH meter with glass electrode at 20 °C. From this pH value subtract the initial pH value (A.2.1).  
A.3 Interpretation of results  
A sample which does not show any physical alteration during incubat ion at 55 ± 1 °C for five days 
and where the pH does not show a difference of more than 0.3 unit from the initial pH is considered 
sterile.  
  
 Annex B  
(normative)  
 
Determination of titratable acidity  
B.1 Apparatus  
B.1.1  Incubator  
B.1.2  Burette ; with soda -lime guard tube  
B.1.3  Porcelain dishes ; white hemispherical of approximately 60 ml.  
B.1.4  Stirring rods ; of glass, flattened at one end.  
B.2 Reagents  
B.2.1  Standard sodium hydroxide solution  
0.1 M. Prepare concentrated stock solution of sodium hydroxide by di ssolving equal parts of sodium 
hydroxide (stocks or pellets) in equal parts of water in a flask. Tightly stopper the flask with a rubber 
bung and allow any insoluble sodium carbonate to settle down for three to four days.  
Use the clear supernatant liquid f or preparing the standard 0.1 M solution. About 8 ml of stock 
solution is required per litre of distilled water. The solution should be accurately standardized 
against acidic potassium phthalate or oxalic acid.  
B.2.2  Phenolphthalein indicator solution  
Dissolve 1 g of phenolphthalein in 110 ml rectified spirit. Add 0.1 M sodium hydroxide solution until 
one drop gives a faint pink coloration.   
B.2.3  Rosaniline Acetate Stock Solution   
Dissolve 0.121 g of rosaniline acetate in approximately 50 ml of rectified s pirit, containing 0.5 ml of 
facial acetic acid. Make up to 100 ml with rectified spirit.   
B.2.3.1  Bench solution   
Dilute 1 ml of stock solution to 500 ml with a mixture of rectified spirit and distilled water in equal 
proportions by volume.  
The stock and t he bench solutions shall be stored in dark brown bottles securely stoppered with 
rubber bungs.  
B.3 Procedure  
B.3.1  Acidity of fresh sample  
Weigh 10.0 g of the sample into each of the two white porcelain dishes of approximately 60 ml 
capacity; add to both 1 0 ml of water and stir to disperse the sample. Prepare from one dilution a 
colour control by adding and stirring 2 ml dilute rosaniline acetate solution. Stir 2 ml phenolphthalein 
solution into the other dilution and while stirring vigorously, add as rapid ly as possible sodium 
hydroxide solution from a 10 ml burette fitted with a soda -lime guard tube, until the colour matches 
the pink colour of the control. The titration shall be done in bright light.   
 B.3.2  Acidity after incubation  
Incubate another 20 g of sample at 55 °C ± 1 °C for five days. Examine the flask each day, then 
shake and replace it in the incubator. If any physical alteration (as indicated in A.2.1) of the content 
is observed the results of the test shall be considered positive and the sample as non -sterile.  
If no alteration takes place during the five days incubation remove the sample from the incubator 
and cool to room temperature. Weigh 10 g of the incubated sample and determine acidity as 
described in B.3.1.  
B.4 Calculation  
B.4.1  Acidity of  fresh sample  
Titratable acidity (as lactic acid) per cent by weight = 
mMV.9  
Where,  
V is the volume in ml of the standard sodium hydroxide required for titration (see B.3.1)  
M is the molarity of the standard sodium hydroxide solution (see B.3), and  
m is the ma ss in g of the sample taken for test (see B.3.1).  
B.4.2  Acidity after incubation  
a) B.4.2.1  Titratable acidity (as lactic acid) percent by weight =  
wMV.9  
Where,  
V is the volume in ml of the standard sodium hydroxide required for titration (see B.3.2.1),  
M is the  molarity of the standard sodium hydroxide solution (see B.3.2.1),  
w is the weight in g of the sample taken for the test (see B.3.2.1)  
b) B.4.2.2  Subtract the value obtained in B.4.1 from the value obtained in B.4.2 which would 
give increase in acidity.  
B.5 Interpretation of results  
A sample which does not show any physical alteration during incubation at 55 °C ± 1 °C for five 
days and where the acidity does not show a difference of more than 0.02 g from the initial acidity is 
considered steril                                                                                                                                     
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