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DRAFT TANZANIA STANDARD  
 
Dried Rosemary ( Rosmarinus officinalis  L.) in cut or ground – 
Specification  
 
 
 
 
 
 
 
  
 
 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS  
                                                                                                     
AFDC 7 (2598) DTZS  
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0. Foreword  
 
Rosemary ( Rosmarinus officinalis  L ) is a small evergreen plant  of the mint family (Lamiaceae), the leaves  
of which are used in flavouring of foods . This Tanzania n standard was prepared to ensure the safety and 
quality of dried whole and ground rosemary  produced for the local and export market s. 
 
In the preparation of t his Tanzania Standard assistance was derived from ISO 11164:1995 Dried 
rosem ary (Rosmarinus officinalis  L.) Specification .  
 
In reporting the results of a test or analysis made in accordance with this Tanzania Standard, if the final 
value observed or calcula ted is to be rounded off, it shall be done in accordance with TZS 4 (see clause 
2). 
 
 
1 Scope  
 
This draft Tanzania Standard specifies the requirements, m ethods of sampling and test  for dried 
rosemary ( Rosmarinus officinalis  L.) leaves in cut and ground f orm for human consumption . 
 
 
2 Normative references  
 
The following referenced documents are indispensable for the application of this standard. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenc ed 
document (including any amendments) applies  
 
 
TZS 4, Rounding off numerical values  
TZS 33, Spices and condiments — Sampling  
TZS 109, Codes of hygiene for food processing units — General  
TZS 118, Foodstuffs — General guidance for the enumeration of micr oorganisms — Colony Count 
Technique at 30 ºC 
TZS 122, Foodstuffs — Microbial examination for salmonella  
TZS 538, Packaging and labeling of foods  
TZS 730 (Part 2) (1st Ed) ISO 16649 (Part 2) - Microbiology of food and animal feeding stuffs – Horizontal 
meth od for the enumeration of -b-glucuronidase -positive Escherichia coli – Part 2 – Colony -count 
technique at 44 0C using 5 -bromo -4-chloro -3-indolyl -b-D-glucuronide  
TZS 731: 2018 (3nd Ed) ISO 7251 - Microbiology of food and feeding -stuffs – Horizontal method f or the 
detection and enumeration of presumptive Escherichia Coli – Most Probable Number Technique  
TZS 799, Foodstuffs – Determination of aflatoxin B 1, and the total content of aflatoxins B 1, B2, G1 and G 2 
in cereals, nuts and derived products – High\-perfo rmance liquid chromatographic method  
TZS 1316, Spices and Condiments - Determination of total ash  
TZS 1317, Spices and condiments — Determination of acid insoluble ash  
TZS 1318, Spices and condiments — Determination of moisture content Entrainment method  
Codex stan 193, Codex general standard for contaminants and toxins in food and feed  
ISO 7609, Essential oils - Analysis by Gas Chromatography on capillary columns – General method  
 
 
3.  Terms and definitions  
 
For the purpose of this standard, the following  terms and definitions shall apply;  
                                                                                                     
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 3.1  
rosemary  
leaves of the species Rosmarinus officinalis  L., belonging to the family Lamiaceae,  
 
3.2  
rosemary leaves  
tough, sessile and linear greyish green leaves on top and whiter and f luffy on their lower part  
 
3.3  
dried rosemary leaves  
dried plant leaves of the rosemary  having  slightly toned -down  colour in cut or in whole  
 
3.4  
ground rosemary  
product obtained by grinding dried rosemary leaves  into different particle sizes  
 
3.5 cut rosemary  
dried rosemary leaves in leaflets or in cut forms   
 
3.6 
extraneous matter  
all matter present in the sample which is not from leaves of the species under consideration  
 
3.7 
food grade container  
container which shall safeguard the hygienic, safety, nutritional, technological, and organoleptic qualities 
of the product  
 
4 Requirements  
 
4.1 General requirements  
Cut or ground rosemary  shall 
i. be free from off odour ; 
ii. have  aromatic, pleasant, fresh and slightly bitter, reminiscent  flavour of rosemary leaves  
iii. have a cha racteristic odour of rosemary l eaves ; 
iv. be free from dirt, fungal growth, insect infestation, insect fragments and rodent 
contamination visible to the naked eye.  
 
 
 4.2 Specific Requirements  
 
4.2.1 Dried rosemary in all forms shall comply with the following specific  requirements : 
 
Table 1 — Physic al-Chemical requirements  for cut and ground rosemary   
S/No Characteristics  Requirements  Test method (See 
clause 2 ) 
i.  Moisture % m/m, max.   11 TZS 1318  
ii.  Total ash, %m/m,  max 8 TZS 1316  
iii.  Acid insoluble ash, %m/m,  max 1 TZS 1317  
iv.  Volatile oil % v/v, min  0.8 ISO 7609  
 
 
4.2.2 Ground rosemary shall be ground to such fineness that all of it passes through a sieve of 500 
micron (0.500 mm).  
                                                                                                     
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 5. Contaminants  
 
5.1 The product shall comply with those maximum pesticide residue limits establ ished by the Codex 
Alimentarius Commission.  
 
5.2 Heavy metals and Metallic contaminants  
 The product shall not contain any heavy and metallic contaminants in excess of levels specified in Table 
2. 
 
Table 2 — Limit for Heavy metals and metallic cont aminants for  whole and ground rosemary  
  
S/No  Characteristics  Limits (Max) mg/kg  Test method  
(see clause 2)  
i  Lead (as Pb)  0.3  Annex A  
ii  Mercury  0.1 Annex B 
 
5.3 Aflatoxin  
 
Whole and ground rosemary  shall not have more than 5 ppb aflatoxin B 1 and total  aflatoxin of 
maximum  10 ppb when tested according to TZS 799 . 
 
 
6. Hygiene  
 
6.1 Whole and ground rosemary  shall be  prepared under good hygienic practices as stipulated in TZS 
109 and shall comply with microbiological limits given in Table 3 when tes ted in accordance with the 
methods specified therein.  
 
 
Table 3 Microbiological limits  for whole and ground rosemary  
 
 
 
7. Sampling and Tests  
 
7.1 Sampling  
Sampling shall be carried out in accordance with the method specified in TZS 33.  
 
7.2 Testing  
Tests shall be done in accordance with methods prescribed in Tables  1, 2 and 3 . 
 
 
 
 S No  Characteristic:  
 Limits 
(Max)  Test method 
1 
 
2 
3 
4 Total aerobic count , CFU/g  
 
Yeasts and  Moulds ,CFU/g  
 
Escherichia coli , CFU/g  
 
Salmonella spp per 25 g.  106 
104 
Absent  
Absent  TZS 118  
 
TZS 730  
 
TZS 731  
 
TZS 122                                                                                                      
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 8. Pack ing, marking  and labelling  
 
8.1 Packing  
Cut and ground rosemary  shall be well packaged in a food grade container.  
  
8.2 Marking and  labelling  
8.2.1 In addition to the requirements of TZS 538 the foll owing specific labelling requirements shall apply 
and shall be legibly and indelibly marked ; 
 
i. Name of the product; rosemary,  
ii. Form of presentation “ground or cut rosemary ” 
iii. species name  (optional) ; 
iv. Net weight;  
v. Name and physical address of the manufact urer/packer/distributor;  
vi. Date of manufacture  
vii. best before date;  
viii. Batch number;  
ix. Instruction for use;  
x. country of origin;  
xi. Storage condition.  
 
8.2.2 Certification mark  
Each container may also be marked with TBS certification mark.  
NOTE:  The use of TBS cert ification mark is governed by provisions of the standards Act 2009.  
Details of the conditions under which a license for the use of TBS certification mark may be 
granted to manufacturers or producers, may be obtained from TBS.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                     
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ANNEX A (Nor mative)  
DETERMINATION OF LEAD IN FOOD BY ATOMIC ABSORPTION 
SPECTROPHOTOMETRIC (AAS) METHOD  
A. Principle  
Organic matter is digested and Lead (Pb) released co -precipitates with Strontium sulphate (SrSO 4). 
Soluble sulphate salts are decanted, and precipitate is converted to carbonate salt, dissolved in acid, and 
determined by AA at 217.0 or 283.3nm.  
 
B. Apparatus  
(a) Atomic absorption spectrophotometer - Operated at 217.0 nm or 283.3nm  
(b) Stirring motor . - With eccentric coupling for stirring centrifuge tubes.  
 
C. Reagents  
(Age all new glassware and all glassware, which has contained high Pb concentration in boiling HNO 3 
before washing. Never let used glassware dry before washing, and always include final HNO 3, rinse 
followed by deionized H 2O rinse).  
 
(a) Stron tium solution.  – 2 %. Dissolve 6 g SrCl 2.6H 2O in 100 ml H 2O. 
 
(b) Ternary acid mixture . - Add 20 ml H 2O4 to 100 ml H 2O, mix, add 100 ml HNO 3 and 40 ml 70% 
HCLO 3, and mix.  
 
(c) Nitric acid  1M. – Add 128 ml redistilled HNO 3 to 500 - 800 ml distilled or deion ized H 2O and dilute 
to 2L. Redistilled HNO 3 may be diluted and used without re -distillation.  
 
(d) Lead standard solutions . - (1) Stock solution . – 1000 µg/ml. Dissolve 1.5985 g Pb(NO 3)2, 
recrystallized, in ca 500 ml 1M HNO 3 in 1L volumetric flask and dilut e to volume with 1M HNO 3. (2) 
Working solutions. - Prepare 100 µg Pb/ml by diluting 10 ml stock solution to 100 ml with 1M HNO 3. Dilute 
1, 3, 5, 10, 15, and 25 µg Pb/ml, respectively).  
 
D. Separation of Lead  
Accurately weigh test portion containing ≤10 g d ry matter and ≥3 µg Pb. Place in 500 ml boiling Kjeldahl 
flask and add 1 ml 2 % Sr solution, C (a) , and several glass beads. Prepare a reagent blank and carry 
through same operations as test portion. Add 15 ml ternary acid mixture, C (b) , for each g dry ma tter and 
let stand ≥ 2 h. Heat under hood or H 2O vacuum manifold system until flask contains only H 2O4 and 
inorganic salts. ( Note:  Take care to avoid material loss from foaming when heat is first applied, and when                                                                                                     
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 foaming occurs soon after material chars. Remove heat and swirl flask before continuing digestion. Add 
HNO 3, if necessary).  
 
Cool digest few min. (Digest should be cool enough to add ca 15 ml H 2O safely, but hot enough to boil 
when H 2O is added).  Wash while still hot 40 – 50 ml tapered -bottom cen trifuge tube and swirl.  Let cool, 
centrifuge 10 min at 350 × ɡ, and decant liquid into waste beaker. (Film -like precipitate on surface may be 
discarded).  Dislodge precipitate by vigorously stirring with eccentric -coupled stirring motor. To compare 
transfer, add 20 ml H 2O and 1m l 0.5M H 2SO 4 to original flask and heat. Do not omit this step even though 
it appears transfer was complete in first wash. Wash hot contents of original digestion flask into centrifuge 
tube containing precipitate. Swirl to mix, cool, centrifuge, and decant  liquid into waste beaker.  
Dislodge precipitate by stirring vigorously, add 25 ml saturated (NH 4)2CO 3 solution (ca 20%), and stir until 
all precipitate is dispersed. Let stand 1 h, centrifuge, and decant liquid into waste beaker.  
After decanting, invert ce ntrifuge tube on paper towel and drain all liquid. Add 5 ml 1M HNO 3 (use large 
volume 1 M HNO 3 in both test solution and blank if ˃25 µg Pb is expected), stir vigorously to expel CO 2 or 
use ultrasonic bath 2 -3 min, let stand 30 min, and centrifuge if preci pitate remains.  (Use same technique 
for all test solution.)  
 
E. Determination  
Set instrument to previously established optimum conditions, using air - C2H2 oxidizing flame and 217.0 or 
283.3 nm resonant wavelength. Determine A of test and blank solutions a nd ≥ 5 standards within 
optimum working range (10 – 80 %T) before and after test readings. Flush burner with 1M HNO 3 and 
check 0 point between readings. Determine Pb from standard curve of A against µg Pb/ml:  
 
          
    
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                     
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 ANNEX B  (Normative)  
DETERMINATION OF MERCURY IN FOOD BY FLAMELESS ATOMIC ABSORPTION 
SPECTROPHOTOMETRIC METHOD   
(Rinse all glassware before use with HNO 3 (1+9)  
 
A. Apparatus  
 
(a) Atomic absorption spectrophotometer . Operating conditions: wavelength 253.7 nm, slit width 160 
µm, lamp current 3 ma, and sensitivity scale 2.5.  
 
(b) Diaphragm pump.  Coat diaphragm and internal parts of pump with acrylic -type plastic spray.  
 
(c) Water condenser . - 12- 18 (id) × 400 mm borosilicate, 24/40 standard taper joint, modified to h old 
6 mm Rasching rings. Fill condenser with Rasching rings to height of 100 ml; then place 20 mm layer of 4 
mm diameter glass beads on top of rings.  
 
(d) Gas inlet adapter . - 24/40 standard taper,  
 
(e) Digestion flask . – 250 ml boiling flask with 24/40 s tandard taper joint.  
 
B. Reagents  
 
(a) Reducing solution . –Mix 50 ml H 2SO 4 with ca 300 ml H 2O. Cool to room temperature and dissolve 
15 g hydroxylamine sulphate, and add 25 g SnCl 2 in solution. Dilute to 500 ml.  
 
(b) Diluting solution.  To 1 L volumetric fl ask containing 300 - 500 ml H 2O, add 58 ml HNO 3 and 67 ml 
H2SO 4. Dilute to volume with H 2O. 
 
(c) Magnesium perchlorate . - Drying agent placed in filter flask. Replace as needed. ( Caution : Mg 
(ClO 4)2 is explosive when in contact with organic substance).  
 
(d) Mercury standard solutions.  - (1) Stock solution. – 1000 µg/ml. Dissolve 0.1354 g HgCl 2 in 100.0 
ml H 2O. (2) Working solution . -1 µg/ml. Dilute 1 ml stock solution to 1 L with 0.5M H 2SO 4. Prepare fresh 
daily.  
 
                                                                                                     
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C. Determination  
Weigh 5.0g test portion into digestion flask; add 25 ml 9M H 2SO 4, 20 ml 7M HNO 3, 1 ml 2% sodium 
molybdate solution, and 5 - 6 boiling chips. Connect condenser (with H 2O circulating through it) and apply 
gentle heat ca 1h. Remove heat and let stand 15 min. Add 20 ml HNO 3-HClO 4 (1+1) through condenser. 
Turn off H 2O circulating through condenser and boil vigorously until white fumes appear in flask. Continue 
heating 10 min. Cool cautiously and add 10 ml H 2O through condenser while swirling liquid in flask. Again 
boil solution 10 min.  Remove heat and wash condenser with three 15 portions H 2O. 
 
Cool solution to room temperature. Completely transfer digest with H 2O to 100 ml volumetric flask and 
dilute to volume with H 2O. Transfer 25.0 ml aliquot from each test solution to another digest ion flask. 
Adjust volume to ca 100 ml with diluting solution, B (b) . 
 
Adjust output of pump to ca 2 L air/min by regulating speed of pump with variable transformer. Connect 
apparatus, except for gas inlet adapter. With pump working and spectrophotometer ze roed, add 20 ml 
reducing solution to diluted aliquot. Immediately connect gas inlet adapter and aerate ca 3 min. (Adjust 
aeration time to obtain maximum A.) Record A, disconnect pressure on “out” side of pump, and open vent 
on filter flask to flush screen.  Prepare reagent blank and standard curve by adding 0, 0.2, 0.4, 0.6, 0.8, 
and 1.0 µg Hg to series of digestion flasks. To each flask, add 100 ml diluting solution. Finally, add 
reducing and aerate standards as for test solution.  
 
Plot standard curve from least squares linear regression of A against µg Hg, use calculator which 
performs linear regression. Determine µg Hg in aliquot from curve. If µg Hg determined falls outside range 
of calibration, repeat determination with smaller aliquot of test solution t o bring µg Hg into region of 
standard curve. From size of aliquot used, determine total µg Hg in original test portion.