TBS/ AFDC 27 ( 6614 ) P3                                                             
               DRAFT TANZANIA STANDARD  
 
 
 
Dried Seaweed – Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                  TANZANIA BUREAU OF STANDARDS  
 
 
 
 
  
 
 
 
 
 
 
 
                
 
 
                                                                                     TBS/ AFDC 27 ( 6614 ) P3                                                             
0. FOREWORD  
 
Seaweed  refers to macroscopic, multicellular, benthic marine algae whi ch includes some 
members of the red, brown and green algae. Seaweed  are essential to marine life for food 
and habitat and they have been a key part of the human diet for thousands of years.   
 
This Tanzania Standard was  prepared in order to ensure quality a nd safety of dried seaweed  
produced locally as well as to give guidance to trader s and consumers of dried seaweed  in 
Tanzania.  
 
In the preparation of this Tanzania Standard, considerable assistance was derived from : 
PNS/BAFPS 85:2012, Dried raw seaweed - Specification  
 
In reporting the results of a test or analysis made in accordance with this Tanzania 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).  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                     TBS/ AFDC 27 ( 6614 ) P3                                                             
1. SCOPE  
 
This Tanzania Standard prescribes the requirements and the methods of samp ling and test 
for dried seaweed  including Spinosum  (Eucheuma  denticulatum  )& Cottonii  (Kappaphycus 
alvarezii  ) species  intended for industrial use or  human co nsumption .  
 
2. NORMATIVE REFERENCES  
 
The following referenced standards are indispensable for the application of this standard. For 
dated references, only the edition cited applies. For undated references, the latest edition of 
the referenced standard (in cluding any amendments) applies.  
 
TZS 4: 200 9, Rounding off numerical values  
 
TZS 109  Code of hygiene for food processing units – General  
 
3. TERMS AND DEFINITIONS  
 
For the purpose of this Tanzania Standard, the following definitions shall apply.  
 
3.1 sea weed  
A cluster of  macroscopic, multicell ular, benthic marine algae. The term includes some 
members of the red, brown and green algae  
 
3.2 clean anhydrous seaweed (CAS)  
seaweed removed of moisture, salt, sand and impurities  
 
3.3 impurities/debris  
other macr ophites , plastic, wood, dirt and other foreign matters other than sand and salt  
 
3.4 contaminants  
any biological or chemical agent, foreign matter, or other sub stances not intentionally added 
to dried seaweed which may compromise food safety and suitabilit y 
 
3.5 food grade containers  
containers which shall safeguard the hygienic, safety, nutritional, technological, and 
organoleptic qualities of the product  
 
4 REQUIREMENTS  
 
4.1. General requirement  
4.1.1 Description  
Dried seaweed shall be a product  produced  by drying fresh  harvested seaweed of single  
specie under the sun or any other method  to attain recommended moisture content (MC) . 
 
 4.1.2 Colour  
The colour of seaweed varies, they may be found in red, purple, green, brown and white.  
 
4.1.3 Impurities  
Dried  seaweed shall not contain impurities in amount that exceed levels specified in Table 1.  
 
4.2 Specific Requirement.  
 
Dried raw seaweed must meet the following criteria as shown in Table 1.  
 
 
 
                                                                                     TBS/ AFDC 27 ( 6614 ) P3                                                             
Table 1: Dried seaweed specific requirement  
Criteria  .K.alvarez ii  E. denticulatum   Test methods  
Moisture content , %max  40 38 Annex A  
Clean anhydrous seaweed(CAS) , % 
min 30 40 Annex B  
Impurities ,%max 3 3 Annex C  
Salt as K Cl,max 25 20 Annex D  
Sand ,%max 1 1 Annex D  
 
 
4.3 Grading  
 
4.3.1 Kappaphycus spp.  
 
The qualit y classification of the above specie seaweed is as prescribed in Table 2 below  
Table 2: Grades of seaweed ( Kappaphycus spp ) 
 
Grade  
 MC 
(% max)  CAS  
(%min)  
 Impurities  
(% max)  
 Salt as KCl  
(% max)  
 Sand  
(% max)  
A 35 35 3 25 1 
B 38 33 3 25 1 
C 40 30 3 25 1 
 
 
4.3.2 E.denticulatum  
 
The quality grading  of the above specie seaweed is as prescribed in table 2 below  
Table 3: Grades of seaweed ( E.denticulatum ) 
Grade  
 MC 
(% max)  CAS  
(%min)  
 Impurities  
(% max)  
 Salt as KCl  
(% max)  
 Sand  
(% max)  
A 33 45 3 20 1 
B 35 43 3 20 1 
C 38 40 3 20 1 
 
Note: In all classifications, 70% from the sample sizes shall pass the analyses for moisture 
content,  clean anhydrous seaweed, impurities, salt (as KCl), and sand in order for a lot to be 
allowed  for each shipment.  
 
5.  CONTAM INANTS   
   
5.1 Heavy Metal contamination  
Dried seaweed shall comply with those maximum heavy metal limits established by the 
Codex Stan 193.  
 
5.2 Pesticide residues  
Dried seaweed shall comply with those pesticide maximum residues limits established in the  
Codex pesticide residues in food online data base.  
6.  HYGIENE  
It is recommended that the product covered by the provisions o f this standard be prepared 
and handled in accordance  with TZS 109 Code of hygiene for food processing units – 
General  
 
7. SAMPLIN G AND TEST S 
                                                                                     TBS/ AFDC 27 ( 6614 ) P3                                                             
7.1 Sampling  
Sampling of dried seaweed shall be done in accordance with Annex E 
 
7.2 Tests  
Tests of dried seaweed shall be done as directed in Table  1 
 
8. PACKAGING , MARKING AND  LABE LLING  
 
8.1 Packaging  
Seaweed shall be packed in food grade co ntainers  
 
8.2 Marking and labelling 
In addition to the requirement of TZS 538, the following specific labelling requirements shall 
apply and shall be legibly and indelibly marked Name of the product  
i. Specie s name  
ii. Class  
iii. Year of harvesting  
iv. Net weight;  
v. Lot/Ba tch number or code number;  
vi. Name and address of producer  and or /packer/distributor  
vii. Country of origin  
viii. Declaration of intended use  
ix. Storage condition  
x. Best before date  
xi. Packing date  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                     TBS/ AFDC 27 ( 6614 ) P3                                                             
 
 
 
Annex A: Determination of moisture of seawe ed 
 
A1 Method A – Determine moisture of seaweed by di rect reading using the moisture meter.  
 
A2 Method B – Oven Drying  
A2.1 Apparatus: Thermally controlled drying oven  
 
A2.2 Procedure:  
a) Weigh one hundred grams of seaweed laboratory sample in a pre -weighe d moisture dish 
the record weight as wo  
 
b) Dry dish plus sample to constant mass at a temperature of 60°C -65°C for  
Eucheuma spp  and 80°C -85°C for Kappaphycus spp. in 12 to 16 hours. Record weight as wf ; 
and 
 
c) Calculate Percent Moisture using the follo wing formula:  
 
                                 wo - wf 
Percent Moisture = --------------  X 100  
                                     wo 
where:  
 
wf  weight of the seaweed after drying  
 
wo  weight of the seaweed before drying  
 
 
Annex B  
 
Calculation for clean  anhydrous seaweed (CAS)  
 
B1. Percent Clean Anhydrous Seaweed is obtained by the formula:  
                 CAS 
% CAS = ----------  x 100   
                   WO 
where:  
 
CAS,  is the mass of clean anhydrous seaweed in grams  
WO,  is the original mass of seawee d taken for analysis in grams  
 
 
Annex C  
 
Determination of impurities/debris  
C1 Weigh 250 grams laboratory sample. Record weight as WO;   
 
C2 Remove debris and other foreign material by hand.  
 
C3 Weigh the impurities/ debris and other foreign materials. Reco rd weight as WD; and  
 
C4 Calculate Percent Impurities/Debris by the formula:  
 
                                    WD 
% Impurities/debris = --------  x 100  
                                    WO 
where:  
WD is the mass of debris/impurities and other foreign ma terials in grams                                                                                      TBS/ AFDC 27 ( 6614 ) P3                                                             
WO is the mass of laboratory sample taken for analysis in grams  
 
 
Annex D  
 
Determination of salt (as KCl) and sand  
 
1. Salt as KCl  
 
D1 Get a one (1) kilogram representative sample of the seaweed raw material;  
 
D2 Weigh 250 g into a 2 -L bea ker; 
 
D3 Add about 900 ml of distilled water, soak the seaweed overnig ht to remove the sand and 
salt. Remove the seaweed, stir the solution very well to completely dissolve the salt;  
 
D4 Decant the solution into a 1 -L volumetric flask and dilute to v olume distilled water. Save 
the sand for further analysis;  
 
D5 Mix the solution well and measure a 50 ml aliquot into a 250 -ml volumetric flask;  
 
D6 Dilute to volume with distilled water. Mix well and measure a 10 ml aliquot into an  
Erlenmeyer flask;  
 
D7 Add 5 d rops of K2CrO4 and titrate with standard 0.100 N AgNO3 to end point (tinge of 
orange brown);  
 
D8 Calculate % salt (as KCl) using the following formula:  
 
                                                                    74.50  
                                V AgNO3 x N AgNO3 x --------  x 100  
                                                                     1000  
% salt (as KCl) =      --------------------------------------------------  
                                                    50           10 
                                        250 x --------  x --------  
                                                   1000       250 
 
II. Sand  
 
D9 Wash the sand from step D4 with distilled water 3 times;  
D10 Put the sand into a pre -weighed porcelain crucible;  
D11 Dry in the oven at 1050C to constant mass. Record weight as Wd; and  
 
D12 Calculate % sand using the following formula:  
 
                    Wd 
% sand = ----------  x 100  
                    250 
 
where:  
 
Wd is the weight of the dried sand in grams  
 
Annex  E 
 
Method of sampling  
 
E1. Definition of terms  
For the purpose of this method, the following definitions shall apply:                                                                                      TBS/ AFDC 27 ( 6614 ) P3                                                             
E1.1 bulk sample – the quantity of seaweed obtai ned by combining and mixing the primary 
sample taken from a specific lot.  
E1.2 consignmen t – the quantity of seaweed dispatc hed or received at one time and 
covered by a particular contract or shipping document. It may be composed of one or more  
lot. 
E1.3 laboratory sample – the quantity of seaweed removed  from the bulk sample and is 
intended f or analyses or other examination.  
E1.4 lot – composed of seaweed belonging to the same sp ecies intended to be uniform in 
characteristics regarding post harvest treatment.  
E1.5 primary sample – a small quantity of seaweed taken from a bag/bale from a lot.  
E2. Sample size  
The size of the sample (n) which is the number of bags/bales  to be taken from a lot depends 
on the size of the lot (N) and shall be in accordance with Table 2.  
 
Table 2 – Sampling plan for seaweed  
 
Lot size (N) Size of the sample (n)  Size of  the sample (n)  
1 to 5 bags/bales All bags/bales  All bags/bales  
6 to 49 bags/bales 5 bags/bales  5 bags/bales  
50 to 199 bags/bales 10% of the bags/bales  10% of the bags/bales  
200 bags/bales or more  √n + 1  
where n= number of bags/bales  
 
where n= number of bags/bales  
 
E3. Sampling procedure  
The sample shall be taken at random from the lot and in order to achieve this, a random  
number table agreed upon between the buyer and seller should be used. If such table is not  
available, the following procedure shal l be adopted:  
 
a) Starting from any bag/bale, count the bags/bales as 1, 2, 3… etc. up to r and so on.  
Withdraw from the lot every rth bag/bale thus counted for sampling, the value of ris equal to  
 
      N 
r = ---- 
      n 
 
where:  
 
N is the total number of  bags/bales in the lot;  
n is the number of bags/bales to be taken (see Table 2)  
b) If r is a fractional number, its value shall be taken as equal to the integral part of it.  
 
E3.1 When the product is in movement, samples may be taken at the time of loading  or 
unloading of the bags/bales. For this purpose, the number of bags/bales to be taken shall also  
be in accordance with Table 2. The value of r shall be calculated as indicated above, and  
every rth bags/bales counted during loading or unloading shall be r emoved for sampling.  
 
E3.2 Take primary samples, by means of an appropriate sampling instrument, from  different 
parts of each bags/bales selected.  
 
E3.3 A series of primary samples should be taken from different positions in the lot.  
 
E4 Bulk sample  
 
E4.1 Thoroughly mix all the primary samples taken as described above to form the bulk  
sample.  
 
E4.2 The size of the bulk sample shall be more than three (3) times the quantity of sample  
required to carry out all the tests required in the specification.                                                                                      TBS/ AFDC 27 ( 6614 ) P3                                                             
 
E5 Labo ratory samples  
 
E5.1 Divide the bulk sample into three (3) or more equal parts. Each part thus obtained  
constitutes a laboratory sample; one (1) of these samples is intended for the buyer and  
another for the seller. The third sample, bearing the seals of t he buyer and of the seller (or of  
their representatives) if they were present at the time of sampling or of the person who  
sampled the lot, shall constitute the reference sample to be used in case of dispute between  
buyer and seller; it shall be kept at a place acceptable to both parties.  
 
E5.2 Samples for test shall be one (1) kilogram.