Blended flour – Specification  
 
Part 1 : Wheat and sweetpotato blended  
flour  
 
 
 
 
 
 
 
 
 
 
 
NOTE: This is a draft proposal and it shall neither be used nor regarded as a Malawi Standard  
________________  
 Published by  
MALAWI STANDARDS BOARD  
 ICS 67 .080.2 0           DMS 1607:2020  
                     First edition  
          
 
 
 
 
DRAFT PROPOSAL  
 
 
  
 ICS 67.080.20                 DMS 1607 :2020
 First edition  
 
 
 
 
 
 
 
Blended flour – Specification  
 
Part 1 : Wheat and sweetpotato blended  
flour  
 
 
 
 
 
 
 
 
 
 
 
Obtainable from the  
Malawi Bureau of Standards  
P O Box 946  
BLANTYRE  
 
Tel: +265 870 488  
Fax: +265 870 756  
       E-mail: mbs@mbsmw.org  
    Website: www.mbsmw.org  
Price based on 4 pages  
© Copyright reserved 
i 
 TABLE OF CONTENTS  
Contents                     Page  
Foreword  ................................ ................................ ................................ ................................ .............................  .i 
Technical Committee  ................................ ................................ ................................ ................................ ..........  .i 
Notice  ................................ ................................ ................................ ................................ ................................ .. .i 
Scope ……………………………………………………………………………………………………………………..  1 
Normative references  ................................ ...............................  ……………………………………………………. 1 
Term s and d efinition s ................................ ................................ .................  ………… …………. ………………… 2 
Essential composition and quality factors  ................................ ................................ ................................ ..........  2 
Fortification and fortification premix……………………………………………………………………………………3  
Food additives  ................................ ................................ ................................ ................................ ...................  3 
Contaminants…………………………………………………………………………………………………………….  3 
Hygiene  ................................ ................................ ................................ ................................ ..............................  4 
Pack aging and labell ing………………………………………………………………………………………………… 4 
Sampling  ................................ ................................ ................................ ................................ .........................  ..4 
 
FOREWORD  
 
This draft proposal  was prepared by MBS/TC 19 , the Technical Committee on  Bread and confectioneries , to 
provide the requirements  for wheat and sweetpotato blended flours . 
 
The draft proposal  has been prepared with consid erable help from the root and tubers  industry  in Malawi . 
Reference was also made  to the Kenya National Workshop Agreement, KNWA 2839 -4:2018 , Blended flour  – 
Specification  – Part 4: Wheat and sweetpotato blend.  
 
Acknowledgement is made for the use of the information.  
 
 
TECHNICAL COMMITTEE  
 
This draft proposal was prepared by MBS/TC 19 , the Technical Committee on  Bread and confectioneries and 
the following companies, organis ations 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 revised every five years or whenever necessary in o rder to keep abreast of progress . 
Comments are welcome and shall be considered when the standard is being revised.   
1 
  
 
 
 
 
 
 
 DMS 1607 :2020                                
DRAFT PROPOSAL   
 
Blended flour – Specification , Part 1 : Wheat and 
sweetpotato blended flour  
 
 
1 SCOPE  
 
This draft proposal  specifies the requirements and methods of sampling and test for wheat and sweet potato  
blended flours prepared from grains of common wheat ( Triticum aestivum  L.) and sweetpotato (Ipomea 
batatas)  chips or a mixture of their flour s thereof intended for human consumption.  
 
 
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 that standard, parties to agre ements based on this draft proposal are 
encouraged to take steps to ensure the use of the most recent edition of the standard s indicated below. 
Information on current valid national and international standards can be obtained from the Malawi Bureau of 
Standards.  
 
MS 19: Label ling of prepack aged foods – General standard;  
 
MS 21:  Food and food processing units – Code of hygienic conditions;  
 
MS 30: Fortified wheat flour  – Specification ;  
 
MS 55: Wheat grain – Specification;  
 
MS 144: Agricultural food products – Determination of crude fibre content – General method;  
 
MS 146: Cereals and cereal products – Sampling . 
 
MS 237: Food additives – General standard;  
 
MS 302: Contaminants and toxins in foods – General standard ; 
 
MS 624:  Nutrition labelling – Guidelines ; 
  
MS 1385 : Sweetpotato flour – Specification ; 
 
MS 1606 : Dried sweetpotato chips – Specification;  
 
MS 1786 : Milled cereal products – Determination of fat acidity;   
2 
  
CAG/GL 23: Guidelines for u se of nutrition  and health claims – Requirements ; 
 
AOAC 2001.06: Total fumonisins in corn, competitive direct enzyme -linked immunosorbent assay ;  
 
ISO 712: Cereals and cereal products – Determination of moisture content – Reference method;  
 
ISO 2171: Cereals, pulses and by-products – Determination of ash yield by incineration;  
 
ISO 762:  Fruit and vegetable products – Determination of mineral impurities content ;  
 
ISO 763: Fruit and vegetable products  – Determination of ash insoluble in hydrochloric acid;  
 
ISO 6579 -1: Microbiology of food and animal feeding stuffs – Horizontal method for the detection, enumeration 
and serotyping of salmonella – Part 1: Detection of Salmonella spp.;  
 
ISO 16050: Foodstuffs – Determination of aflatoxin B1, and the total content of aflatoxins B1, B2, G1 and G2 
in cerea ls, nuts and derived products – High-performance liquid chromatographic method ; 
 
ISO 16649 -2: Microbiology of food and animal feeding stuffs – Horizontal method f or the enumeration of beta -
glucuroni dase -positive Escherichia coli – Part 2: Colony -count technique at 44 degrees C using 5 -bromo -4-
chloro -3-indolyl beta -D-glucuronide ; and 
 
ISO 21527 -2: Microbiology of foo d and animal feeding stuffs – Horizontal method for the en umeration of yeasts 
and moulds – Part 2: Colony count technique in products with water activity less than or equal to 0.95 . 
 
 
3 TERM S AND DEFINITION S 
 
For the purposes of this draft proposal , the following terms and definitions shall apply.  
 
3.1  
blended flour  
mixture of milled wheat and sweetpotato . This can also be obtained by mixing the food crop produce before  
milling of their flours thereof  
 
3.2  
food grade packaging material  
material which will safeguard the hygienic, nutritional, technological and organoleptic qualities of the product  
 
3.3  
foreign matter  
organic and inorganic material s (such as sand, soil, glass) other than flour   
 
3.4 
musty  
stale, mouldy or dump smell  
 
3.5 
wholesome  
free from disease and physiological deterioration (such as but not limited to decay, breakdown, f reezing 
damage) or adulteration /contamination, that appre ciably affects their appearance , edibility, the keeping quality 
of the produce or market val ue 
 
 
4 ESSENTIAL COMPOSITION AND QUALITY FACTORS  
 
4.1 Raw materials  
 
Wheat and sweetpotato blended flour shall be prepared by blending wheat flour complying with MS 30 or 
wheat grains complying  with MS 55 and sweet potato flour complying with MS 1385 or dried sweetpotato chips 
complying with MS 1606 .  
3 
  
4.2 General requirements  
 
Wheat and sweetpotato blended flour shall be : 
 
4.2.1  Of charact eristic colour of wheat grains/flour and sweetpotato chips/ flour from which they were 
prepared ;  
 
4.2.2  Free from foreign matter such as insects, fungi or dirt ;  
 
4.2.3 Free from musty or other objectionable odour; and  
 
4.2.4 Wholesome and fit for human consumption . 
4.3 Specific requirements  
 
4.3.1 The minimum content of sweetpotato flour in the blended product shall be 10  %. 
 
4.3.2  Wheat and sweetpotato blended flour shall comply with the specific chemical requirements specified 
in Table 1  when tested in accordance with test methods specified therein.  
 
Table 1 – Compositional requirements for wheat and sweetpotato blended flour  
 
1 2 3 4 
S/N Characteristic  Requirement  Method of test  
1 Crude fibre , % m/m maxa. 5 MS 144  
2 Moisture, % m/m, max.  14 ISO 712  
3 Total ash, % m/m, max . 3 ISO 2171  
4 Fat acidity, mg KOH  per 100 g of product, m/m, max.  50 MS 1786  
5 Acid insoluble ash, % by m/m, max . 0.4 ISO 5985  
a Percentage mass on dry matter basis   
 
4.4 Microbiological limits  
 
Wheat  and sweetpotato blended flour  shall be free from pathogenic organisms and shall comply with the 
microbiological limits indicated in Table 2.   
 
Table 2  – Microbiological limits  
 
1 2 3 4 
S/N Characteristic  Limit  Method  of test  
1 Yeasts and m oulds cfu/ g, max.  103 ISO 21527 -2 
2 Escherichia coli , cfu/g 102 ISO 16649 -2 
3 Salmonella sp.  in 25 g  Absent  ISO 6579 -1 
 
 
5 FORTIFICATION AND FORTIFICATION PREMIX  
 
Fortification and its premix formulation to wheat and sweetpotato blended flour shall compl y with provisions 
provided in MS 30.  
 
 
6 FOOD ADDITIVES  
 
Only those food additives listed und er this product in MS 237, may  be used and only within the limits specified.  
 
 
7 CONTAMINANTS  
 
7.1 Heavy metals  
  
4 
 Wheat and  sweetpotato  blended  flour shall comply  with maximum levels of heavy metals permitted in MS 302 . 
 
7.2 Pesticide residues  
 
The product shall conform to the maximum residue limits established by the Codex Alimentarius Commission . 
 
7.3 Mycotoxins  
 
Wheat and sweetpotato blended flour  shall comply with mycotoxin limits specified in Table 3 when tested in 
accordance with test methods specified therein . 
 
 
 
Table 3 – Mycotoxin limits for wheat and sweetpotato  blended flour  
 
1 2 3 4 
S/N Mycotoxin  Maximum limit, µg/kg  Test method  
1 Total aflatoxins  10  
ISO 16050  2 Aflatoxin B1  5 
3 Fumonisins  2000  AOAC 2001.06 0 
 
 
8 HYGIENE  
 
Wheat and sweetpotato blended flour shall be manufactured in premises complying with the hygienic practices 
stipulated in MS 21.  
 
 
9 PACK AGING AND LABELLI NG 
 
9.1 Pack aging 
 
9.1.1  Wheat and sweetpotato blended flour shall be packaged in food grade materials . 
 
9.1.2  When the product is packaged in sacks, these shall be clean, sturdy and strongly sewn or sealed.  
 
9.2 Labelling  
 
9.2.1  In addition to the requirements in MS 19, the following specific labelling requirements shall apply and 
shall be legibly and indelibly marked:  
 
9.2.1.1 Name of product shall be “W heat and sweetpotato blended flour’’  or “Sweetpotato and wheat blended 
flour” . The first name shall be that  of dominant flour in the blend ; 
 
9.2.1.2 The name and address of the manufacturer, packer, distributor, importer, exporter or vendor ; 
9.2.1.3 Brand name/registered trade mark, if any;  
9.2.1.4 Lot or b atch number  in code or in clear format;  
9.2.1.5 Net weight in metric units ;  
9.2.1.6 The statement “Store in a cool dry place and away from contaminants”;   
9.2.1.7 The statement “F or human consumption”;  
9.2.1.8 Country of origin ; 
9.2.1.9 Date of manufacture ; 
9.2.1.10 Best before date ; and 
9.2.1.11 Instructions for disposal of used package.  
  
5 
 9.2.2  Nutrition labelling  
 
The amount of nu trients in the wheat and sweet potato  blended flour shall be declared on the  label in 
accordance with MS 624 . 
 
9.2.3  Nutrition and health claims  
 
Wheat and sweet potato blended flour may have claims on nutrition  and health. Such claims when declared 
shall be in complianc e with CAG /GL 23 .  
 
 
10 SAMPLING  
 
Sampling shall be d one in accordance with MS 146 .  
 
 
ICS 67.080.20                                     DMS 1607 :2020
 First 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 
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incorporate advanced technology.  To bring the advantages of standard ization 
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Under this scheme, manufacturers who 
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