AFDC 05(6094) P3  
 
 
                  
DRAFT TANZANIA STANDARD  
 
 
 
 
 
 
Saccharin (food grade)  — Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                    TANZANIA BUREAU OF STANDARDS                                                                                                                       
AFDC 05( 6094)P3  
 
 Food grade saccharin — Specification  
 
0.  Foreword  
 
Saccharin (1,2 -Benzisothiazole -3(2H) -one-1,1-dioxide, 3 -oxo-2,3-dihydrobenzo[d]isothiazol -1,1-dioxide) and 
its sodium, calcium and potassium salts are widely utilised in the food industry as non -nutritive artificial 
sweeteners. They are used as a substitute  for cane sugar in the production of diet and low -calorie foods. They 
are colourless crystals or white crystalline powders with faint aroma and about 300 – 500 times sweeter than 
sucrose (table sugar).  
 
In the Codex Alimentarius Commission International N umbering System, saccharins are assigned as INS 954 
and the FAO/WHO Joint Experts Committee on Food Additives (JECFA) established the Acceptable Daily 
Intake (ADI) for saccharin and its salts at 0 – 5 mg/kg body weight.   
 
 
 
In preparation of this draft Tanzania standard assistance was drawn from India standard;  
IS5345:2001 Food grade Saccharin – Specification published by Bureau of India Standards (BIS)  
 
 
This standard has been developed to keep up with advancements of the saccharin industry and to ensur e the 
safety of food additive products traded.  
 
In reporting the result of a test or analysis made in accordance with the Tanzania standard, if the final value 
observed or calculated is to be rounded off, it shall be done in accordance with TZS 4: (see cla use 2)  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
  
1 Scope  
 
This Draft Tanzania standard specifies requirements, sampling and test methods for food grade saccharin.  
 
2 Normative references   
 
The following referenced documents are referred to in the text in such a way that some or all 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 972.25, Lead in food. Atomic absorption spectrophotometric method  
 
Codex Stan 192, General standard for the labelling of food additives when sold as such  
 
TZS 539, M ethods of test for the assessment of odours and taint from packaging materials used for food 
stuffs  
 
TZS 538 , Labelling  of pre \-packaged foods — General requirements  
 
CAC/GL 50, General guidelines on sampling  
 
 ISO 760, Determination of water  — Karl Fischer Method (General method)  
 
TZS 4,  Rounding off numerical values  
 
TZS 109, Food processing units – Code of hygiene  
 
3 Terms and definitions  
 
For the purposes of this document, the following terms and definitions apply.  
 
3.1 saccharin  refers to substances utilized in the food industry as non -nutritive artificial sweeteners  
 
3.2 artificial/non -nutritive sweeteners is artificial substance that has a similar taste to sugar other than 
sugar u sed to sweeten food or drink.  
 
3.3  food grade material   
material, made of substances which are safe and suitable for their intended use and which w ill not impart any 
toxic substance or undesirable odour or flavour to the product  
 
 
4 Requirements  
 
4.1 General requirements  
 
4.1.1 Saccharin  shall be, free from off odors, foreign matter and adulterants  
 
4.1.2 Food grade saccharin shall be:  
 
a) white crystals or white crystalline powder;  
 
b) odourless or with a faint aromatic odour,  
 
c) slightly soluble in water, soluble in basic solutions and sparingly soluble in ethanol. 1 g of product 
shall be soluble in 1.5 ml of water or basic solutions and in about 50 ml of ethanol.  
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
  
 
 
 
 
4.2 Specific requirements  
 
Food grade saccharin shall comply with the specific requirements given in Table 1 when tested in accordance 
with the test methods specified therein.  
 
 
Table 1 — Specific requirements for food grade saccharin   
S/N Characteristic  Requirement  Test method  
    
i) Purity as C7H5NO3S, % m/m (dry matter 
basis)  99 – 101 Annex A  
    
ii) Moisture content, %m/m, max.  1 ISO 760  
    
iii) Acidity and alkalinity at room temperature  To pass test  Annex B  
    
iv) Benzoic and salicylic acid  To pass test  Annex C  
    
v) Readily carbonizable substances  To pass test  Annex D  
     
 
5. Food additives  
Only the food additives permitted by CODEX STAN 192 in the manufacture of food grade saccharin  may be 
used without exceeding the limits.  
 
6 Hygiene  
6.1 Food grade saccharin  shall be prepared and packaged in premises built and maintained under hygienic 
condition in accordance with TZS 109.  
 
6.2   Food grade  saccharin  shall be free from pathogenic organisms.  
 
6.3 Contaminants  
 
Food grade saccharin shall comply with the Maximum Levels of contaminants given in Table 2 when tested in 
accordance with the test methods specified therein.  
 
Table 2 — Limits for contaminants for food grade saccharin   
S/N Contaminant  Maximum level  Test method  
i) Lead (Pb), mg/kg, max.  1 AOAC 972.25  
    
ii) Arsenic (As), mg/kg, max.  2 AOAC 952.13  
    
iii) Selenium (Se), mg/kg, max.  30 Annex E  
    
iv) Toluenesulfonamides, mg/kg, max.  25 Annex F  
    
 
7 Sampling  
 
Representative samples of the product shall be drawn in accordance with  CAC/GL 50.  
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
  
 
 
 
 
 
8 Packaging , marking and labelling  
 
8.1 The product shall be securely packaged in containers made of food grade materials  with accordance to 
TZS 539 . The packages shall preserve the quality of the product, prevent entry of light and preclude 
contamination from the external environment.  
 
 
 
8.2 Marking and Labelling  
 
8.2.1  In addition to the requirements of TZS 538 and TZS 116, the product label shall be legibly and indelibly 
labelled with the following:  
 
(i) Name of the product as Saccharin with the words ‘Food Grade’;  
(ii) Name and physical address of the manufacturer/distributor;  
(iii) Net weight in metric units;  
(iv) Batch/lot number;  
(v) stora ge condition ;  
(vi) Date of manufacture  
(vii) Expiry date  
(viii) Instruction for use . 
(ix) Statutory warnings (For industrial use only)  
 
8.2.2  The language on the label shall be “Kiswahili” or Kiswahili and English. A second language may be 
used depending on the designated market.  
 
8.2.3  The packages of the buns may also be marked with the 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 licences are granted, may be obtai ned from TBS . 
 
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
  
 
 
Annex A  
(normative)  
 
Assay: Test for purity  
 
 
 
A.1 Procedure   
 
Dry 10 g of product in a hot air oven at 120 °C for 4 hours. Accurately weigh about 0.5 g ( M) of the dried 
sample and dissolve it in 75 ml of hot water. Quickly cool the mixture and add 2 – 3 drops of phenolphthalein 
indicator. Titrate the mixture with 0.1 N sodium hydroxide till the endpoint and record the volume of NaOH 
used ( V). 
 
Each ml of 0.1 N sodium hydroxide is equivalent to 18.32 mg of C7H5NO3S.  
 
Therefore, percentage purity (as C7H5NO3S), m/m (dry matter basis) shall be calculated from:  
 
18.32 
 V 
 
100 M 
 
1000  
  
 
where  
 
- is the volume, in millilitres, of 0.1N NaOH used and  
 
- is the mass, in grams, of dried sample dissolved in 75 ml of hot water.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
                                                                                                                         
AFDC 05( 6094)P3  
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Annex B  
(normative)  
 
Test for acidity and alkalinity  
 
 
 
C.1 Procedure   
 
Dissolve 1 g of sample in 10 ml of freshly boiled and cooled water. Add one drop of phenolphthalein indicator.  
No pink colour shall appear.  
 
Add one drop of 0.1 M sodium hydroxide. A pink colour shall appear.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
  
 
 
 
Annex C  
(normative)  
 
Test for benzoic and salicylic acid  
 
 
 
D.1 Procedure   
 
Add ferric chloride drop wise to 10 ml of a hot, saturated solution of the sample. No precipitate or violet colour 
shall appear.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                                        
AFDC 05( 6094)P3  
 
    AFDC 5 ( 6094 ) P3 
 
11 
 
 
DRAFT TANZANIAN STANDARD  
 
 
 
Annex D  
(normative)  
 
Test for readily carbonizable substances  
 
 
 
E.1 Reagents   
 
E.1.1  Sulphuric Acid  
 
E.1.2 Matching Fluid ; Composed of 0.1 ml of cobalt chloride solution (see E.1.2.1), 0.4 ml of ferric chloride  
solution (see E1.2.2), 0.1 ml cupric sulphate  solution (see E.1.2.3) and 4.4 ml of distilled water.  
 
E.1.2.1 Cobalt chloride solution: Dissolve 65 g of cobaltous chloride (CoCl2.6H2O) in a mixture of 25 ml of  
hydrochloric acid and 975 ml of distilled water. Place exactly 5 ml of this solution in a 250 -ml iodine flask, add 
5 ml of 3 percent hydrogen peroxide solution and 15 ml of 20 percent sodium hydroxide solution. Boil for 10 
minutes, cool, and add 2 g of pot assium iodide and 20 ml of 25 percent sulphuric acid. When the precipitate 
has dissolved, titrate the liberated iodine with 0.1N sodium thiosulphate solution, adding starch as indicator. 
Each millilitre of 0.1N sodium thiosulphate is equivalent to 23.8 mg of cobaltous chloride. Adjust the final 
volume of the solution by adding an adequate amount of the hydrochloric acid and distilled water mixture so 
that each millilitre contains 59.5 mg of cobaltous chloride.  
 
E.1.2.2 Ferric chloride solution: Dissolve 55 g of ferric chloride (FeCl3.6H2O) in a mixture of 25 ml  
hydrochloric acid and 975 ml of distilled water. Place 10 ml of this solution in a 250 -ml iodine flask. Add 15 ml 
of distilled water and 3 g of potassium iodide, and allow the mixture to stand for 15 minutes. Dilute with 100 ml 
of distilled water, and titrate the liberated iodine with 0.1N sodium thiosulphate solution, adding starch as 
indicator. Each millilitre of 0.1N sodium thiosulphate is equivalent to 27.03 mg of ferric chloride. Adjust the 
final volume of the solution by adding enough of the hydrochloric acid and distilled water mixture to make each 
millilitre contain 45.0 mg of ferric chloride.  
 
E.1.2.3 Cupric sulphate solution: Dissolve 65 g of cupric sulphate (CuSO4.5H2O) in a mixture of 25 ml of 
hydrochloric acid and 975 ml of distilled water. Place 10 ml of this solution in a 250 -ml iodine flask, add 40 ml 
of distilled water, 4 ml of acetic acid and 3 g of potassium iodide. Titrate the liberated iodine with 0.1N sodium 
thiosulphate  solution, adding starch as indicator. Each millilitre of 0.1N sodium thiosulphate is equivalent to 
24.97 mg of cupric sulphate. Adjust the final volume of the solution by adding enough of the hydrochloric acid 
and distilled water mixture to make each mill ilitre contain 62.4 mg of cupric sulphate.  
 
E.2 Procedure  
 
Dissolve 0.2 g of the sample in 5 ml of sulphuric acid. Keep the solution at 48 °C – 50 °C for 10 minutes. The 
colour of the resultant solution shall not be darker than that of the matching fluid i n E.1.2 (a very light 
brownish -yellow).  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   AFDC 5 ( 6094 ) P3 
 
12 
 
 
DRAFT TANZANIAN STANDARD  
 
Annex E  
(normative)  
 
Test for Selenium  
 
 
 
F.1 Reagents   
 
F.1.1 Selenium Stock Solution: Transfer 120 mg of metallic selenium (Se) into a 1000 -ml volumetric flask,  
add 100 ml of dilute nitric acid (1 in 2). Gently warm the solution on a steam -bath and dilute to volume with 
distilled water. Transfer 5 ml of this solution into a 200 -ml volumetric flask, dilute to volume with distilled water, 
and mix. Each millilitre of  this solution contains 3 µg of selenium ions (Se).  
 
F.1.2 Standard Selenium Solution: Just prior to the test, transfer 20 ml of selenium stock solution (60 µg Se)  
into a 200 mm x 25 mm test tube, add 20 ml of hydrochloric acid, and mix.  
 
F.1.3 Sample Solu tion: Transfer 2 g of the sample to a 250 -ml Erlenmeyer flask, and cautiously add 10 ml of  
30 percent hydrogen peroxide solution. After the initial reaction has subsided, add 6 ml of 70 percent 
perchloric acid, heat slowly until white fumes of perchloric a cid are copiously evolved and continue heating 
gently for a few minutes to ensure decomposition of any excess peroxide. If the solution is brownish in colour 
due to non -decomposed organic matter, add a small amount of hydrogen peroxide solution and heat ag ain to 
white perchioric acid fumes, repeating, if necessary until complete decomposition of the organic matter when 
a colourless solution is obtained. Cool, add 10 ml of distilled water and filter into a 200 mm x 25 mm test tube. 
Wash the filter paper with  hot water until the filtrate measures 20 ml, add 20 ml of hydrochloric acid and mix.  
 
F.1.2  Procedure  
 
Place the test tubes containing the standard selenium solution and the sample solution in a water -bath, and 
heat until the temperature of the solution r eaches 40 °C. To each tube, add 400 mg of ascorbic acid, stir until 
dissolved and maintain at 40 °C for 30 minutes. Cool the solution, dilute with distilled water to 50 ml and mix.  
 
Any pink colour  produced by the sample shall not exceed that produced by the standard selenium solution.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   AFDC 5 ( 6094 ) P3 
 
13 
 
 
DRAFT TANZANIAN STANDARD  
Annex F  
(normative)  
 
Test for toluenesulfonamides  
 
 
 
G.0 Two methods have been specified. Any method may be used depending upon the facilities available.   
 
G.1 Method 1 – Gas Chromatography  
 
G.1.1 Reagents  
 
G.1.1.1 Methvlene chloride: Use a suitable pure grade, equivalent to the product obtained by distillation in all  
glass apparatus.  
 
G.1.1.2 Internal standard stock solution: Transfer  100 mg of 95 percent n -ticosane into a 10 -ml volumetric  
flask. Dissolve in n -heptane, dilute to volume with the same solvent, and mix.  
 
G.1.1.3 Stock standard preparation: Transfer 20 mg each of reagent grade o -toluenesulfonamide and p -
toluenesulfonamide into a 10 -ml volumetric flask. Dissolve in methylene chloride, dilute to volume with the 
same solvent, and mix.  
 
G.1.1.4 Diluted standard preparation: Pipette into five lo -ml volumetric flasks, 0.1, 0.25, 1.0, 2.5 and 5.0 ml  
respectively, of the ‘stock sta ndard preparation’. Pipette 0.25 ml of the ‘internal standard stock solution’ into 
each flask, dilute each to volume with methylene chloride and mix. These solutions contain 250 µg of n -
tricosane, plus respectively, 20, 50, 200, 500 and 1000 µg per ml of e ach toluenesulfonamide, plus 250 mg of 
n-tricosane.  
 
G.1.1.5 Test preparation: Dissolve 2 g of the sample in 8 ml of 5 percent sodium bicarbonate solution. Mix 
the solution thoroughly with 10 g of chromatographic siliceous earth (Celite 545 or equivalent).  Transfer the 
mix into a 25 mm x 250 mm chromatographic tube having a fritted glass disk and a Teflon stopcock at the 
bottom, and a reservoir at the top. Pack the contents of the tube by tapping the column on a padded surface, 
followed by tamping firmly fr om the top. Place 100 ml of methylene chloride in the reservoir and adjust the 
stopcock so that 50 ml of eluate is collected in 20 to 30 minutes. To the eluate, add 25 µl of ‘internal standard 
stock solution’. Mix, and then concentrate the solution to a vo lume of 1 ml in a suitable concentrator tube fitted 
with a modified Snyder column, by using a Kontes tube heater maintained at 90 °C.  
 
 
G.1.2  Procedure  
 
G.1.2.1 Inject 2.5 µl of the test preparation (see G.1.1.5) into a suitable gas chromatograph equipped with a  
flame -ionization detector. The column should be of glass, approximately 3 m in length and 2 mm in inside 
diameter and packed with 3 percent phenylmethyl silicone on l00 - to 120 -mesh equivalent to 150 - to 125 -
micron IS test sieve and silanised calci ned diatomaceous silica.  
 
NOTE : The glass column should extend into the injector for on -column injection and into the detector base to 
avoid contact with metal.  
 
The carrier is helium flowing at a rate of 30 ml per minute. The injection port, column, and d etector are 
maintained at 225°C, 180°C and 250°C respectively. The instrument attenuation setting should be such that 
2.5 µl of the ‘diluted standard preparation’ containing 200 µg per ml of each toluenesulfonamide gives a 
response of 40 to 80 percent of f ull-scale deflection. Record the chromatogram, note the peaks for o -
toluenesulfonamide, p -toluenesulfonamide, and the n -tricosane internal standard, and calculate the areas for 
each peak by suitable means. The retention times for o -toluenesulfonamide, p -toluenesulfonamide, and n -
tricosane are about 5, 6 and 15 minutes, respectively.  
 
 
G.1.2.2 In a similar manner, obtain the chromatograms for 2.5 µl  portions of each of the live ‘diluted standard  
preparations’ and for each solution, determine the areas of the  o-toluenesulfonanude, p -toluenesulfonamide, 
and n -tricosane peaks.    AFDC 5 ( 6094 ) P3 
 
14 
 
 
DRAFT TANZANIAN STANDARD  
 
From the values thus obtained, prepare standard curves by plotting concentration of each toluenesulfonamide, 
in µg per ml versus the ratio of the respective toluenesulfonamide  peak area to that of n -tricosane. From the 
standard curve determine the concentration, in µg per ml, of each toluenesulfonamide in the ‘test preparation’. 
Divide each value by 2 to convert the result to parts per million of toluenesulfonamide in the 2 g s ample taken 
for analysis.   
 
NOTE: If the toluenesulfonamide content of the sample is greater than 500 parts per million, the impurity may 
crystallize out of the methylene chloride concentrate (see G.1.1.1). Although this level of impurity exceeds that 
perm itted by the specification, the analysis may be completed by diluting the concentrate (usually 1: 10 is 
satisfactory) with methylene chloride containing 250 µg of n -tricosane per ml, and by applying appropriate 
dilution factors in the calculation. Care sha ll be taken obtain a homogeneous solution by completely dissolving 
any crystalline toluenesulfonamide.  
 
G.2 Method 2 – Thin Layer Chromatography  
 
G.2.1  Apparatus  
 
G.2.1.1  Flat glass plates (200 mm x 100 mm)  
 
G.2.1.2  Micropipette  
 
G.2.1.3  Developing chamber  lined with filter paper  
 
G.2.2 Reagents  
 
G.2.2.1 Silica gel  
 
G.2.2.2 Chloroform  
 
G.2.2.3 Methyl alcohol  
 
G.2.2.4 Ammonia solution – strong  
 
G.2.2.5 4 –Sulphamoylbenzoic acid – reference material  
 
G.2.2.6 Toluene –2–sulfonamide acid – reference material  
 
G.2.2.7 Sodium hypochloride solution: Diluted with water to contain 0.5 percent (m/v) of available chlorine.  
 
G.2.2.8 Potassium iodide  
 
G.2.2.9 Starch mucilage  
 
G.2.2.10 Glacial acetic acid  
 
G.2.2.11 Solution A: 4 volumes of methyl alcohol plus 1 volume of  acetone plus 0.5 percent (m/v) of the 
sample  
 
G.2.2.12 Solution B: 4 volumes of methyl alcohol plus 1 volume of acetone plus 0.005 percent (m/v) of the 4 -
sulphamoylbenzoic acid  
 
G.2.2.13 Solution C: 4 volumes of methyl alcohol plus 1 volume of acetone plus 0.005 percent (m/v) of the  
toluene -2-sulfonamide.  
 
G.2.3 Procedure  
 
G.2.3.1 Prepare suspension of silica gel G . Spread the suspension on the plates about 0.25 mm thick. 
Allow  to stand until the coating sets and then dry the plates at 105 °C to 110 °C for one hour. Protect the   AFDC 5 ( 6094 ) P3 
 
15 
 
 
DRAFT TANZANIAN STANDARD  
plates from moisture. Pour into the developing chamber sufficient quantity of mobile phase (100 volumes of 
chloroform + 50 volumes of methyl alcohol + 11.5 volume of strong ammonia solution) to form a layer about 
15 mm deep. Close  the tank for one hour at 20 °C to 27 °C. Remove the narrow strips of the coating, about 5 
mm inside from the margins of the chromatoplate. Using micropipette apply separately to the chromatoplates 
2 ml each of solutions A, B and C. These spots should be a bout 25 mm from the bottom of the plates and not 
less than 25  
- from the sides of the plates. The diameter of the spots should not be more than 6 mm. Dry the spots and 
place the chromatoplates in the developing chamber at 20 °C to 27 °C until the mobile phas e has ascended to 
the 150 mm line.   
 
Remove the plates and dry them in current of warm air. Then heat at 105 °C for five minutes. Spray the hot 
plates with the sodium hypochlorite solution. Dry in a current of cold air until sprayed area of the plate below 
the line of application give at most  a faint blue colour with a drop of a mixture, prepared by dissolving 0.5 
percent (m/v) of potassium iodide in starch mucilage containing 1 percent (m/v) of glacial acetic acid. Avoid 
prolonged exposure to cold air. Spray the plates with the same mixture. The spots in the chromatograms 
obtained with solution (B) and (C) should be more intense than any corresponding spots in the chromatogram 
obtained with solution (A).  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   AFDC 5 ( 6094 ) P3 
 
16 
 
 
DRAFT TANZANIAN STANDARD  
 
Bibliography  
 
 
 
[1] IS 5345: 1996 (Reaffirmed in 2001) , Sodium saccharin food grade  — Specification (Second revision)  
 
[2] JECFA monograph, Saccharin  
 
[3] Food chemicals codex (5th Edition)