PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative  Meeting  
ii Foreword  1 
 2 
The Philippine National Standard (PNS) for Corn (maize) grits ( Zea mays Linn. ) – 3 
Grading & classification ( PNS/BAFPS 15:2004 ) was developed to provide uniform 4 
guidance on the  classification of corn grits based on their physical characteristics and 5 
current practices existing in the sectors concerned. It includes sections on the essential 6 
composition and quality factors, classification and grading, sampling and methods of 7 
analys is, determination of moisture content, packing, marking, contaminants and 8 
hygiene.  9 
 10 
In 2017, the Bureau of Agriculture and Fisheries Standards (BAFS) took the initiative to 11 
review and revise the Standard to account for results of recent studies and advance s on 12 
the grading and classification of corn grits. This revision is in accordance with the 13 
protocol of the Bureau’s Standards Development Division (SDD) to review and, if 14 
applicable , revise standards every two  years, especially those that pose risk to 15 
cons umer safety and health. A Technical Working Group (TWG) for the revision of the 16 
Standard was created and authorized under Special Order Nos. 301 and 814 Series of 17 
2017. The TWG was composed of the following agencies and institutions: National Food 18 
Authorit y, National Food Authority – Food Development Center, Department of 19 
Agriculture Corn Program, Philippine Center for Postharvest Development and 20 
Mechanization, University of the Philippines Los Baños, National Corn Competitiveness 21 
Group, Inc., and Philippin e Maize Federation Inc.   22 
 23 
This document was drafted in accordance with the editorial rules of the BPS Directives, 24 
Part 3.  25 
 26 
This Standard cancels and repeals PNS/BAF PS 15:2004. 27 PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
1 
 1 Scope   28 
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This standard applies to corn grits for direct human consumption milled from kernels of 30 
corn, also known as maize, Zea mays  L. 31 
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2 Normative r eferences  33 
 34 
The following documents are referred to in the text in such a way that some or all of 35 
their content constitutes requirements of this document. For dated references, only the 36 
edition cited applies. For undated references, the la test edition of the referenced 37 
document (including any amendments) applies.  38 
 39 
PNS/BAFS 15 :2004, Corn (maize) grits (Zea mays Linn. ) – Grading & classification  40 
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3 Terms and d efinitions  42 
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For the purpose s of this document , the following terms and definitions apply . 44 
 45 
3.1 46 
aflatoxin  47 
group of highly poisonous and carcinogenic compounds which are produced by strains 48 
of the fungi, Aspergillus flavus  and Aspergillus parasiticus  on suitable substrate such as 49 
corn, peanuts, copra, and other oilseeds, cassava, etc.  50 
 51 
3.2 52 
corn grits  53 
milled corn grain s where the outer covering  (pericarp)  and germ  (embryo)  have been 54 
removed  leaving only the endosperm that passed through different sieve sizes  55 
 56 
3.2.1 57 
corn grits No. 10  58 
corn grits with particle size from 1.69 mm to 2.00 mm which passed through US 59 
Sieve No. 10 but are retained in  US Sieve No. 12  60 
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3.2.2 62 
corn grits No. 12  63 
corn grits with particle size from 1.42 mm to 1.68 mm which passed through US 64 
Sieve No. 12 but are retained in  US Sieve No. 14  65 
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3.2.3 67 
corn grits No.14  68 
corn grits with particle size from 1.20 mm to 1.41 mm which passed through US 69 
Sieve No. 14 but are retained in US S ieve No. 16  70 
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3.2.4 72 
corn grits no. 16  73 
corn grits  with particle size from 1.01 mm to 1.19 mm  which passed through US 74 
Sieve No. 16  but are retai ned in US Sieve No. 18  75 PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
2 
  76 
3.2.5  77 
corn grits No. 18  78 
corn grits with particle size from 0.842 mm to 1.00 mm which passed through US 79 
Sieve No. 18 but are retained in US Sieve No. 20  80 
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3.3 82 
discolored grits  83 
corn grits  which are materially discolored and damaged by external heat or 84 
fermentation  85 
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3.4 87 
filth  88 
impurities of animal origin (including dead insects)   89 
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3.5 91 
foreign matter  92 
all matters other than corn grits such as sand, gravel, dirt, pebbles, stones, lumps of 93 
earth, clay, mud , chaff, straw, and seeds of other crops  94 
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4 Essential composition and quality factors  96 
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4.1 Odor  98 
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Corn grits shall have the characteristic odor of corn a nd shall not have  any abnormal or 100  
foreign odor . 101  
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4.2 Color  103  
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Corn grits shall reasonably be in uniform color  according to type.  105  
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4.3  Moisture content  107  
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Water content of corn grit s, expressed in percent  wet basis as received.  109  
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5 Classification  111  
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Corn grits sh all be classified according to type.  113  
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5.1 White corn grits   115  
 116  
White corn grits  with  not more than the permitted percentage of corn grits of other 117  
colors as indicated in the quality grade requirement for corn grits. A slight tinge of color 118  
other than white shall not affect their classification as white corn grits.  119  
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 123  PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
3 
  124  
5.2 Yellow corn grits  125  
 126  
Yellow corn grits  which with  not more than the permitted percentage of corn grits of 127  
other colors as indicated in the quality grade requirement for corn grits. A slight tinge of 128  
color other than yellow shall not affect their classification as yellow corn grits.  129  
 130  
5.3 Mixed corn grits  131  
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Consist of corn grits of various colors that do not meet the color requirements for either 133  
white or yellow corn grits . 134  
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5.4 Pigmented corn grits  136  
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Consist of corn grits of various colors (e.g., purple, red, brown, blue, black).  138  
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6 Grading  140  
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Corn grits shall conform to the quality grade requirements specified in Table 1. 142  
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Table 1 – Quality grade requirements of corn grits  144  
 145  
Grade factors , % by 
weight maximum  Grade  
Premium 
grade  Grade 
no. 1 Grade 
no. 2 Grade 
no. 3 Grade 
no. 4 
Moisture content  14.00  14.00  14.00  14.00  14.00  
Aflatoxin ( food) , µg/kg  20 20 20 20 20 
Filth  0.1 0.1 0.1 0.1 0.1 
Discolored grits  Trace  0.50  1.00  2.00  3.00  
Foreign matter  Trace  0.50  0.80  1.00  2.00  
Grits of other colora Trace  0.50  1.50  3.00  5.00  
Grits of other sizes  1.00  4.00  7.00  10.00  13.00  
a Does not apply to pigmented corn grits  
 146  
7 Sampling and methods of analysis  147  
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Sampling method to be used for ascertaining conformance to the requirements of this 149  
specification shall be in accordance with the established procedures of the competent 150  
authority.  151  
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Sampling should be done by classifiers or quality assurance personnel deputized by the 153  
competent authority.  154  
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8 Determination of moisture content  156  
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The moisture content of the grains shall be determined using verified and properly 158  
adjusted  moisture meters . 159  PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
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  160  
9 Pack aging 161  
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Corn grits shall be directly  packed in  polyethylene bag before placing inside 163  
polypropylene bag  or any appropriate container  to protect them from  contamination . 164  
Corn grits shall be properly packed in 1, 2, 5, 10 , or 25 kg  packing size to facilitate 165  
handling and transport.  166  
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10 Labeling  168  
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10.1  Each container shall have a label or legible characters grouped on the same side, 170  
stamped in indelible ink to provide the following:  171  
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10.1.1 Name and type of the product;  173  
10.1.2 Grade and grits size;  174  
10.1.3 Net weight in kilograms ; 175  
10.1.4 Name and address of miller , packer, or distributor ;  176  
10.1.5 Date of milling ; 177  
10.1.6 Moisture content; and  178  
10.1.7 Lot or batch no.  179  
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10.2 The label may also have the following optional information:  181  
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10.2.1  Storability depending on packaging material  (e.g., best consumed before [date] if 183  
vacuum packed, or [date] if not vacuum packed ) 184  
10.2.2  Nutrition information (e.g., protein, fat, carbohydrates, minerals, vitamins, 185  
dietary fiber)  186  
10.2.3  Functionality (e.g., antioxidant capacity, glycemic index)  187  
 188  
11 Contaminants  189  
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11.1 Mycoto xins  191  
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Corn grits shall not contain more than 20 µg/kg aflatoxin.  193  
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11.2 Heavy metals  195  
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Corn grits shall comply with those maximum levels for heavy metals established by the 197  
Codex Alimentarius  Commission for this commodity.  198  
 199  
11.3 Live i nsects  200  
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Corn grits shall be free of any live stored grain  pest . 202  
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11.4  Pesticide residues  204  
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Corn grits shall comply with those maximum residue limits  established by the Codex 206  
Alimentarius Commission for this commod ity. 207  PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
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  208  
12 Hygiene  209  
 210  
Corn grits shall  be prepared and handled in accordance with appropriate sections of the 211  
Recommended International Code of Practice  - General Principles of Food Hygiene  212  
(CAC/RCP 1 -1969 , Rev. 2003 ) and other relevant Codex texts and PNS such as the PNS 213  
Code of Hygienic Practice for the Processing and Handling of Corn Grits (PNS/BAFS 214  
142:XXXX).   215  PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
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 Annex A  216  
(informative)  217  
 218  
US sieve size equivalents  219  
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US sieve size  Tyler equivalent  Opening  
mm  in 
- 2 ½ Mesh  8.00  0.312  
- 3 Mesh  6.73  0.265  
No. 3 ½  3 ½ Mesh  5.66  0.233  
No. 4  4 Mesh  4.76  0.187  
No. 5  5 Mesh  4.00  0.157  
No. 6  6 Mesh  3.36  0.132  
No. 7  7 Mesh  2.83  0.111  
No. 8  8 Mesh  2.38  0.0937  
No. 10  9 Mesh  2.00  0.0787  
No. 12  10 Mesh  1.68  0.0661  
No. 14  12 Mesh  1.41  0.0555  
No. 16  14 Mesh  1.19  0.0469  
No. 18  16 Mesh  1.00  0.0394  
No. 20  20 Mesh  0.841  0.0331  
No. 25  24 Mesh  0.707  0.0278  
No. 30  28 Mesh  0.595  0.0234  
No. 35  32 Mesh  0.500  0.0197  
No. 40  35 Mesh  0.420  0.0165  
No. 45  42 Mesh  0.354  0.0139  
No. 50  48 Mesh  0.297  0.0117  
No. 60  60 Mesh  0.250  0.0098  
No. 70  65 Mesh  0.210  0.0083  
  221  PHILIPPINE NATIONAL STANDARD  PNS/BAFS 15 :20XX 
Corn (maize) grits – Grading and classification  
Working draft  
For Public Consultative Meeting  
7 
 Bibliography  222  
 223  
CAC/RCP 1 -1969 (Rev. 2003),  General Principles of Food Hygiene  224  
 225  
Codex Alimentarius Volume 2. (1993). Pesticide residues in food, 2nd ed. 226  
 227  
Codex Alimentarius Volume 7. (1996). Cereals, pulses, legumes and derived products and 228  
vegetable proteins, volume 7, 2nd ed.  229  
 230  
National Food Authority. (2002). Primer on Philippine Grains Standardization Program . 231  
 232  
PNS/BAFS 142:XXXX, Code of hygienic practice for the processing and handling of  corn 233  
grits  234