a  
  
 
 
 
 
 
 
 
 
 
 
 
 ICS 67.040                         DMS 299:2021
                Second edition  
                                                                                                                             
 
 
 
 
 
DRAFT PROPOSAL  
 
 
 
 
 
 
Baking powder – Specification  
 
 
 
 
 
 
 
 
 
 
 
 
NOTE: This is a draft proposal and it shall neither be used nor regarded as a Malawi standard  
 
 
 
 
 
 
 
  
  ICS 67.040            DMS 299 :2021  
           Second edition  
 
 
 
 
 
 
 
 
Baking powder  – Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Obtainable from the  
Malawi Bureau of Standards  
Moirs Road  
P O Box 946  
BLANTYRE  
 
Tel: +265 1 870 488  
Fax: +265 1 870 756  
E-mail:  mbs@mbsmw.org  
Web -site: www.mbsmw.org  
 
Price based on 7 pages  
 
© Copyright reserved   
 i TABLE OF CONTENTS  
  
Contents                                                                                                                                                     page      
 
Foreword …………………………… ………………………………………………………………………………… .. i 
Technical committee ……………………………………………………………………………………………………..  i 
Notice ………………………………………………………………………………………………………………………  i 
Scope ……………………………………………………………………………………………………… ……………..  1 
Normative references ……………………………………………………………………………………………………  1 
Essential composition and quality requirements……………………………………………………………………..1  
Hygiene……………………………………………………………………......…………………………………………  2 
Contaminants …………………………………………………………………………………………………………….  2 
Packing and labelling ……………………………………………………………………………………………………  2 
Sampling ………………………………………………………………………………………………………………….  2 
Annex A : Sampling of baking powder …………………... …………………………………………………………….  3 
Annex B : Determination of available carbon dioxide ……… …………….. …………………………………………  5 
 
 
FOREWORD  
 
This draft proposal  was prepared by MBS/TC 19, the Technical Committee on  Bread and confectioneries,  to 
provide requirements  and methods of  sampling and  testing for baking powder .  
 
In preparation of this draft proposal, reference was made to the following standard:  
 
Uganda  standard, US 571:2018 , Baking powder  – Specification.  
 
Acknowledgement is made for the use of the information.  
 
 
TECH NICAL COMMITTEE  
 
This draft proposal was prepared by MBS/TC 19, the Technical Committee on Bread and confectioneries , and 
the following companies, organizations a nd institutions were consulted : 
 
Bakhresa Grain Milling;  
 
Blantyre City Council;  
 
Bread Talk;  
 
Bvumbwe Agricultural Research Station;  
 
International Potato Center Malawi;  
 
Lilongwe University of Agriculture & Natural Resources;  
 
Ministry of Health – Department of Nutrition, HIV & AIDS;  
 
National Fortification Alliance;  
 
Universal Industries Limited; and  
 
University of Malawi.  
 
NOTICE  
 
This standard shall be reviewed every five years, or earlier whenever it is necessary, in order to keep abreast 
of progress. Comments are welcome and shall be considered when the standard is being reviewed .1 
                                                  DMS 299:2021  
DRAFT PROPOSAL   
 
Baking powder – Specification  
 
 
1 SCOPE  
 
This draft proposal  prescribes the requ irements and the methods of  sampling and testing for baking powder.  
 
 
2 NORMATIVE REFERENCES  
 
The following standards contain provisions which, through reference in this text, constitute provisions of this 
draft proposal . All standards are subject to revision and, since any reference to a standard is deemed to be a 
reference to the latest edition of the standard, parties to  agreements based on this draft proposal  are 
encouraged to take steps to ensure the use of the most recent editions of the standards indicated below. 
Information on currently valid national and international standa rds can be obtained from the Malawi Bureau of 
Standards:  
 
MS 19:  Labelling of prepacked foods – General standard;  
 
MS 21:  Food and food processing units – Code of hygienic conditions;   
 
MS 302: Contaminants and toxins in food – General standard;  
 
MS 1240 : Sodium bicarbonate – Specification ; and 
 
ISO 760:  Determi nation of water – Karl Fischer m ethod (General method)  
 
 
3 ESSENTIAL COMPOSITION AND QUALITY REQUIREMENTS  
 
3.1 Essential ingredients  
 
3.1.1 Sodium b icarbonate , conforming  to MS 1240 . 
 
3.1.2 Edible starches such as maize starch and cassava starch or other ne utral material such as calcium 
lactate, anhydrous calcium sulphate and sodium sulphate,  conforming to relevant Malawi standards.  
 
3.1.3  One or a combination of the following acid reacting componen ts: 
 
3.1.3.1  Sodium acid pyrophosphate with or without mono acid calcium phosphate;  
 
3.1.3.2  Mono acid calcium phosphate with or without dicalcium orthophosphate;  
 
3.1.3.3  Potassium hydrogen tartrate or tartaric acid or a mixture of both;  
 
3.1.3.4   Acid compounds of aluminium; and  
 
3.1.3.5  Glucono delta lactone . 
 
3.2 General requirements  
 
3.2.1 Baking powder  shall be in the form of a free-flowing, whitish powder  and free from dirt, any off odour  
and colour .  
 
3.2.2 Baking powder  shall be  free from insect s or fungus  infestation and adulterants. It shall also be free 
from any other harmful  or injurious foreign matter.  
 
NOTE : The appearance  and odour shall be determined by or ganoleptic tests.   
   2 3.3 Specific requirements  
 
Baking powder shall also conform to the specific  require ments given in  Table 1  when tested in accordance 
with the methods given in column 3 of Table 1 . 
 
Table 1 – Requirements for baking powder  
 
1 1 2 3 
S/N Characteristic  Requirement  Method of test  
1 Available carbon dioxide, % (m/m), min.  12.0 Annex B  
2 Moisture, % (m/m), max.  2.0 ISO 760  
 
 
4 HYGIENE  
 
Baking powder  shall be manufactured in premises complying with the hygienic practices stipulated in MS 21.  
 
 
5 CONTAMINANTS  
 
Baking powder shall comply with the maximum levels for contaminants and toxins in accordance with MS 302.  
 
 
6 PACK AGING AND LABELLING  
 
6.1 Packaging  
 
Baking powder shall be packed  in clean, sou nd and air -tight food grade materials that will ensure the safety 
and integrity of the product throughout the shelf life. 
 
6.2 Labelling  
 
In addition to the requirements of MS 19, the following specific labelling requirements shall apply and shall be 
legibly and indelibly marked:  
 
6.2.1 Name of the product as “ Baking powder” ; 
 
6.2.2 Name and address of the manufacturer,  packer, distributor, importer, exporter or vendor;  
 
6.2.3 Date of manufacture;  
 
6.2.4 Best before date ; 
 
6.2.5 Lot identification;  
 
6.2.6 Net weight, in metric units ; 
 
6.2.7 Instructions for use ; 
 
6.2.8 Storage instruction; and  
 
6.2.9  Instructions on disposal of used package.  
 
 
7 SAMPLING  
 
Representative  samples   of  baking   powder   shall  be  drawn   in  accordance with   the  procedure   given   in 
Annex A.   
   3 ANNEX A  
(Normative)  
 
SAMPLING OF BAKING POWDER  
 
A.1 GENERAL REQUIREM ENTS OF SAMPLING  
 
In draw ing, preparing, storing and handling samples, the followi ng precautions a nd directions shall be 
observed:  
 
A.1.1 Samples shall be taken in a protected place not exposed to damp  air, dust or soot;  
 
A.1.2 The sampling instrument s hall be clean and dry when used;  
 
A.1.3 Precautions shall be taken to protect the samples, the material  being sampled, the sampling 
instrument and the containers for samples  from adventitious contamination;  
 
A.1.4 The samples shall be placed in clean, odourless and dry glass  contain ers. The sample containers 
shall be of such size that they are  almost completely filled by the sample;  
 
A.1.5 Each  container shall be se aled air -tight after filling and marked  with full details of sampling, batch or 
code number, name of the  manufacturer and other important  particulars of the consignment;  
 
A.1.6  Samples shall be stored in such a man ner that the temperature  of the material does not vary und uly 
from the normal temperature; and  
 
A.1.7  Sampling shall be done by a person, agreed to  between the  purchaser and the vendor and in the 
presence of the purchaser (or his  representative)  and the vendor (or his representative).  
 
 
A.2 SCALE O F SAMPLING  
 
A.2.1  All the containers in a consignment belonging to the same  batch or m anufacture shall constitute a lot.  
Samples shall be tested from such lot for ascertaining conformity  of the material to the requirements of the 
specification.   
 
A.2.2 The number of containers to be tested from a lot shall depend on  the size of the lot and shall be in 
accordance with Table 2.  
 
Table  A.2 – Number of containers to be selected for sampling  
 
 
 
 
 
 
 
 
 
A.2.3 The containers to be selected for sampling shall be chosen at  random from the lot and , for this purpose, 
random number tables  shall be used. In case such tables are not  available, the following procedure may be 
adopted:  
 
Starting from any container, count them as 1, 2, 3 , r and so on, in one order. Every rth container thus counted 
shall be chose n, r, being the integral part of N/n, where N is the total  number of containers in the lot and n is 
the number of containers to  be selected (see  Table 2 ). 
 
 
 
 1 2 3 
S/N Total number of containers 
in a lot (N)  Number of containers to 
be selected (n)  
1 Up to 50  3 
2 51 to 100  4 
3 101 to 300  5 
4 301 to 500  6 
5 501 and above  7  
   4 A.3 TEST SAMPLES AND REFEREE SAMPLES  
 
A.3.1 Preparation of individual samples  – Empty out the conten ts of the container on a sheet of paper 
and mix thoroughly. Cone and quarter  as often as necessary till about 75  g of the material is left. From this  
take about 15 g of the material and divide it into three equal parts.  Each part so obtained shall constitute an 
individual sampl e representing  the container and shall be transferred immediately with partic ulars given  in 
A.1.5 . The individual samples so obtained shall be divided  into three  sets in such a way that each set has a 
sample represe nting each selected  container. One of these sets shall be marked for the purchaser, the  other 
for the vendor and the third for the referee.  
 
A.3.2 Preparation of composite sample  – From the material from  each selected container remaining after 
the individual sample has been  taken, equal quantities of material shall be taken and mixed together so  as to 
form a composite sa mple weighing n ot less than 160 g. This composite  sample shall be divided into three 
equal parts and transferred to  clean dry glass containers and labelled with the particulars given  in A.1.5. One 
of these composite samples shall be marked for the  purchase r, the other for the vendor and the third for the 
referee.  
 
A.3.3 Referee samples – Referee samples shall consist of a set of  individual samples and a composite 
sample marked for this purpose and shall bear the seals of the purchaser and  the vendor. These shall be kept 
at a place agreed to between the two.  
 
 
A.4 NUMBER OF TESTS  
 
A.4.1  Tests for requirements given in 4.1 and available carbon dioxide  shall be conducted on each of the 
samples constituting a set of individual  test samples . 
 
A.4.2  Tests for the remaining characteristics, namely, arsenic and lead,  shall be conducted on the composite 
sample.  
 
 
A.5 CRITERIA FOR CONFORMITY  
 
A.5.1 The lot shall be considered satisfactory in respect of the requirements  of A.4.1 if each individual 
sample satisfies all the requirements.  
 
A.5.2 The lot shall be considered satisfa ctory in respect of the requirements of A.4.2 if the test results on 
the composite sample satisfy the  corresponding requirements.  
 
A.5.3  The lot shall be d eclared to be in conformity with all the require ments of this specification, if it has been 
found satisfactory in accordance  with A.5.1 and A.5.2. 
 
 
 
 
 
 
 
 
 
 
 
  
   5 ANNEX B  
(Normative)  
 
DETERMINATION OF AVAILABLE CARBON DIOXIDE  
 
 
B.1 INTRODUCTION  
 
Two methods have been prescribed. Any of these can be used  depending on the facilities available.  
 
B.1.1 Method 1  
 
B.1.1.1  Apparatus  
 
Schroedte r's alkalimeter , as shown in  Figure 1. 
 
B.1.1.2 Reagent  
 
Sulphuric Acid , sp gr 1 .84. 
 
B.1.1.3 Procedure  
 
Fill bulb (A) with water and bulb (B) with sulphuric acid to a  height of 25 mm above the port (C) through which 
carbon dioxide escapes  into the acid. Weigh the alkalimeter  (M). Introduce about 1 g  of the  sample through 
the side opening (D) into the decomposition flask (E). Weigh the alkalimeter again  (M2) Open the stopcock (F) 
and allow about 25 ml of water to flow into the flask (E). Allow the initial vigorous reaction to  subside. Place 
the apparatus over a low flame and boil the solution for  about 3 minutes. Aspirate carbon dioxide -free air 
through the solution  by applying suction at (G), the air first passing through soda lime. Weigh  the alkalimeter 
again  (M1). 
 
 
 
 
 
   6 B.1.1.4 Calculation  
 
Available carbon dioxide (per cent by mass) is equal to  
100  × 𝑀2−𝑀1
𝑀2−𝑀 
Where,  
 
𝑀2 is mass of alkalimeter with sample, before decomposition;  
 
𝑀1 is mass of alkalimeter with sample, after decomposition ; and 
 
𝑀 is mass of alkalimeter before introducing the sample . 
 
B.1.2 Method 2 
 
B.1.2.1 Apparatus  
 
Gasometric assembly,  as assembled, is shown in figure  2. 
 
The apparatus consists of a 250 ml, wide  mouthed extraction flask  (A) made of heat resistant glass, conne cted 
by a short bent glass tube to a rubber tube (B). This is connected by a  two-way stopcock (C) to a gas measuring 
tube (D) which is graduated  in ml;  at 20 oC with zero mark at the point just below the top and  graduated up to 
500 ml. Additionally connected to flask A is a 40 ml burette (H) graduated in ml. The gas measuring tube is 
connected to a le velling tube (F) through a  rubber tube (E) having a pinchcock (P) to control the  flow of solution.  
 
 
 
 
 
   7 B.1.2.2 Reagent  
 
Displacement solution  – Dissolve 100 g sodium chloride or sodium sulphate in 3 50 ml water. Add accurately 
1 g sodium bicarbonate  (complying to MS 1240)  and 2 ml methyl ora nge (0·5 % aqueous solution) and  then 
enough Sulphuric acid or hydrochloric acid to turn the solution acid  (solution turns to pale pink). Stir until all 
CO2 is removed. This solution is used  in gas measuring tube and levelling bulb and seldom needs correction.  
 
B.1.2.3 Procedure  
 
B.1.2.3.1  Accurately weigh 2 .5 g sample into flask (A). Using the two -way stopcock (C), connect with both gas 
measuring tube (D) and levelling tube (F) to the atmosphere and through a funnel on the open end of tube (F), 
fill both tubes with displacement solution up to the zero mark of tube (D). Connect the decomposition flask (A) 
with rubber tube (B) and turn the stopcock so that th e gas measuring tube is connected to flask A and 
disconnected from the atmosphere. Fill burette (H) with distilled water up to the 40 ml mark and let the 
apparatus stand for 1 to 2 min  so that the temperature and pressure within the apparatus comes to room  
conditions. Open pinchcock (P) and bring down the solution level in tube F to reduce pressure within the 
apparatus. Collect the displaced solution in a glass beaker and reserve for re -use later. Slowly add 35 ml of 
distilled water to decomposition flask, from burette H.  
 
B.1.2.3.2  To allow uniform mixing of content s and complete evolution of CO 2, occasionally rotate the 
decomposition flask by swirling and boil the flask and its contents over a tripod stand using a Bunsen burner. 
To prevent overflowing of displacement solution in levelling tube, fill to a level lower than the overflow capacity. 
When the mixture in flask (A) foams up and the foam reaches the neck of the flask, stop heating and quickly 
immerse the decomposition flask in cold tap water kept in a tray below. Also pour water over the decomposition 
flask while rotating it to bring the co ntents to the temperature of water in the tray. When  this happens wait for 
5 min  to secure equilibrium. Equalize pressure in the measuring tube by pouring solution in levelling tube, 
using the pinchcock P if necessary and read the volume V in the measuring  tube. 
 
B.1.2.4 Calculation  
 
Deduct from this volume V, the volume of distilled water  added namely 35 ml to get the corrected volume of 
CO 2 evolved after  decomposition at atmospheric temperature and pressure.  
 
The volume of CO 2 evolved, in millilitres, at normal temperature and pressure shall be calculated as follows:  
 
𝑉2=𝑇2
𝑃2×𝑉1𝑃1
𝑃2𝑇1 
 
Where,  
 
𝑉2 is the volume of carbon dioxide calculated at normal temperature and pressure;  
 
𝑉1 is the  – 35 ml = corrected volume of carbon diox ide evolved after decomposition;  
 
𝑃2 is the  normal pressure (760 mm);  
 
𝑃1  is the corrected barometric pressure at temperature  𝑇1; 
 
𝑇2  is the normal temperature (273  oK or 0  oC); and 
 
𝑇1 is the observed tempe rature of displacement solution.  
 
1 g mole (44 g) of carbon dioxide, at NTP will occupy 22 400 ml, that is, 22 400 ml of CO 2 at NTP, weigh 44 g.  
 
V2 ml CO 2 a obtained from 2.5 g of baking  powder NTP will weigh, in g : 
 
𝑉2
22 400×44
1 
 
Therefore, available carbon dioxide percent by mass =100
2.5×𝑉2
22400×44= 40×𝑉2×44
22 400 
  
 
ICS 67.040            DMS 299 :2021  
          Second edition  
 
 
 
 
 
THE MALAWI BUREAU OF STANDARDS              CERTIFICATION MARK SCHEME  
The Malawi Bureau of Standards is the 
standardizing body in Malawi under the aegis 
of the Ministry of Industry and Trade.  Set up in 
1972 by the Malawi Bureau of Standards Act 
(Cap: 51:02), the Bureau is a parastatal body 
whose activities aim at formulating and 
promoting the general adoption of standards 
relating to structures, commodities, materials, 
practices, operations and from time  to time 
revise, alter and amend the same to 
incorporate advanced technology.  To bring the advantages of standardization 
within the reach of the common consumer, the 
Bureau operates a Certification Mark Scheme. 
Under this scheme, manufacturers who 
produce goods that conform to national 
standards are granted permits to use the 
Bureau’s “Mark of Quality” depicted below on 
their products.  This Mark gives confidence to 
the consumer of the commodity’s reliability.