PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
1 
 Foreword  
 
This Philippine National Standard  (PNS)  was developed in response to the development of the 
Codex Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava 
Products  (CAC/RCP 73 -2013) , which was adopted in 201 3. The  PNS is therefore , an adoption of 
this Codex  COP , with modifications to suit the local production practices in the Philippines.  
A Technical Working Group (TWG) was create d through Special Or der No. 105  Series of 2014  to 
develop the draft  COP  for the Reduction of Hydrocyanic Acid (HCN)  in Cassava and Cassava 
Products . The TWG represented the relevant agencies of the Department of Agriculture (DA),  
Department of Health (DOH), Department of Science and Technology (DOST), and the academe. 
Public consultations were conducted in  Regions 5,  7, 10 and the National Capital Region (NCR), 
which represented the major hubs of cassava production and trade. Comments and 
recommendations were solicited fro m the relevan t government agencies, academe, and private 
sector and non -government organizations.  Therefore, this COP  is the final output of the public -
private sector collaboration between, and among the TWG and the relevant stakeholders , who 
participated  in the public consultations.     
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
2 
 I. INTRODUCTION  
 
1. Hydrogen cyanide or hydrocyanic a cid (HCN) is a volatile compound which evaporates at 
temperatures over 28°C and dissolves rapidly in water. It may easily be lost during transport, 
storage and analysis of samples.  
 
2. HCN  is a chemical compound that can be released from cyanogenic glycosides that are  
natural cons tituents of some plants such as  bitter almonds, sorghum, cassava, lima beans, 
stone fruits and bamboo shoots. Therefore , reduction and removal meas ures of  HCN  should 
focus on the precursor i.e. cyanogenic glycosides and cyanohydrins.  
 
3. HCN  may be toxic to humans and animals, and the severity of the toxicity depends on the 
quantity consumed.  In humans, the symptoms of acute cyanide intoxication from 
inadequately prepared cassava can include: rapid respiration, drop in blood pressure, rapid 
pulse, dizziness, headache, stomach pains, vomiting, diarrhea, mental confusion, twitching 
and convulsions . In animals, it affect s the reproductive organs including birth rates and an 
increase number of neonatal deaths, impaired thyroid function,  and behavioral effects 
including increasing ambivalence and slower response time. Death due to cyanide poisoning 
can occur when the cyanide limit exceeds the limit of what an individual is able to detoxify.  
 
4. Cassava ( Manihot  esculenta  Crantz ) is a woody shrub extensively cultivated as an annual 
crop in tropical and subtropical r egions for its edible starchy enlarged  root. Cassava is a 
major source of carbohydrates in the human diet.  However, one of the limiting 
characteristic  of cassava used for  food and feed is the cyanogenic glycosides  content of  its 
roots  and leaves . The amount of the cyanogenic glycosides varies depending on the cultivar 
and growing conditions . The cassava plants, including the roots, also contain the enzyme 
linamarase  that breaks down the cyanogenic glycosides to release cyanohydrin, which 
dissociates at low levels of acidity to produce HCN . The extent of the breakdown of the 
cyanogenic glycosides (and the eventual rel ease of HCN  depending  on the amount of 
linamarase p resent in the cassava tissue ); the extent of the disruption of the tissue; the 
acidity of the product;  and the heat treatment are key factors in determining the 
concentration of residual cyanogens in cassava products. It is evident that high 
concentrations  of cyanogenic glycosides may result in higher concentrations of HCN .  
 
 
 
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
3 
 5. The CAC through  the J oint F ood and Agriculture Organization (FAO) – World Health 
Organization (WHO)  Expert Committee on Food Additives (JECFA) , previously developed 
Maximum Levels (MLs) for HCN  in Sweet Cassava, Bitter Cassava, Edible Cassava Flour and 
Gari (a product obtained from processing cassava roots ). These are the following:  
 
 Sweet Cassava  - less than 50  mg/kg of HCN  
 Bitter Cassava (must not be eaten raw)  - more than 50  mg/kg of HCN  
 Edible Cassava F lour - must not exceed 10  mg/kg  HCN  
 Gari - must not exceed 2mg/kg as free HCN  
 
6. In the Philippines, cassava is popularly known as balinghoy  or kamoteng -kahoy , and is being 
advocated as an alternative staple to rice under the Department of Agriculture  (DA) - Food 
Self-Sufficiency Program  (FSSP) . The DA, through the Bureau of Agriculture and Fisheries 
Standards (BAFS) , develop ed two (2) Philippine National Standards  (PNS) related to cassava 
which are  harmonized with the Codex  standards , namely : 
 
 PNS: Dried Cassava Chips and Granules (PNS/BAFPS 29:2009) ; and  
 PNS: Fresh Rootcrop – Sweet Cassava – Classification and Grading (PNS/BAFPS 
119:2013) . 
 
7. This Code outlines measures that have been proven to prevent and/or reduce 
concentrations of HCN  in cassava and its  products. When applying this C ode for cassava 
processing, methods should be carefully chosen from the viewpoint of benefit and 
feasibility. In addition, th is should be implemented in accordance with the relevant nation al 
and international legislations .  
 
8. It is recognized that reasonable application of technological measures such as Good 
Manufacturing Practices (GMP), can be taken  as an intervention  to remove or reduce 
significantly the concentrations of HCN  in cassava and its products.  
 
II. Scope  
 
9. This COP  intends to provide national and local authorities, producers, traders, processors  
and other relevant stakeholders  with guidance on how to produce  and process  cassava  
roots  and its products  such as grates, chips, granules, flour and starch  with safe 
concentrations of residual cyanogenic compounds.  
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
4 
 III. Definitions  
 
For the purpose of this Code, the following terms are operationally defined:  
 
Cassava – (Manihot esculenta Crantz) also called manioc, yuca, balinghoy, mogo, mandioca, 
kamoteng -kahoy, tapioca -root , and manioc root : a woody shrub extensively cultivated as an 
annual crop in tropical and subtropical regions for its edible starchy, enlarged root.  The 
following are the different cassava types/forms:  
 
Bitter Cassava – variety with high concentration of HCN , which  normally more than 50 
mg/kg HCN  by fresh weight (e.g. Sutan 2 & Mcol 1684) . 
 
Sweet Cassava  – variety with low concentration of HCN, which  normally less than 50 
mg/kg HCN  by fresh weight (e.g. Lakan 1 & Rayong 5) . 
 
Cassava Products - refer to cassava chips, granules, grates, flour, starch, adhesives and other 
industrial and pharmaceutical products . 
 
Chilling – refers to the process of maintaining the product a temperatures not exceeding 4 ˚C in 
any part of the product.  
 
Clean Water  - water that does not compromise food safety in the circumstances of its use.  
 
Cooling – refers to the process where t he product is cooled at ambient or room temperature 
(30˚C to 35 ˚C). 
 
Cyanogenic G lycosides  – are secondary metabolites that are found in various plant tissues and 
produce HCN  upon hydrolysis , which may be toxic to humans and animals, the severity of the 
toxicity depends on the quantity consumed.  
 
Drying – removal or reduction of moisture content (MC) of cassava products through solar, 
oven or mechanical dryer to prolong the shelf life of cassa va products.  
 
Freezing – refers to the process of maintaining the product at a temperature equal to or below 
– 18 ˚C in any part of the product.  
 
Fresh Cassava  – refers to roots that have been harvested, unprocessed , and stored prior to 
processing without any sign of deterioration .  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
5 
 Hydrogen C yanide or Hydrocyanic Acid (HCN) - refers to total hydrocyanic acid which maybe 
enzymatically released from a cyanogenic glycoside as well as any free or unbound HCN  in 
cassava, e xpressed in milligrams of HCN  per kilogram of fresh cassava and its products (mg/kg) . 
 
Potable Water  - water which meets the quality standards of drinking water such as described in 
the WHO Guidelines for Drinking Water Quality . 
 
IV. Typical Cassava Production  Processes  
 
10. Processing cassava for food and feed uses  is effective in reducing cyanogenic compound 
content to minimum concentrations , when done appropriately . Inadequate or improper  
processing sometimes can lead to high residues of HCN  in the final product.  
 
11. The production process for cassava products varies with the intended product. Some 
examples  include cassava grates, chips, granules, flour, starch, and other industrial and 
pharmaceutical products . Figures 1 – 5, illustrate the step s in the production proc esses of 
some cassava products.  
 
Grated Cassava  
 
12. For grated cassava, the production process involves selection , cleaning, peeling, washing, 
grating, dewatering , cooling /chilling/freezing , drying, sieving (depending on use) and 
pack ing. The process typically follows the steps listed below:  
 
a. Selection:  Select the fresh and healthy cassava roots from the lots for processing of 
cassava. Preferably the selected cassava roots are sweet type and 7 - 9 months old.  
b. Cleaning:  This is done manually to remove the soil and other foreign materials in the 
skin so as not to contaminate the produce . 
c. Peeling : This is done  manually with clean stainless knives  or mechanically using stainless 
steel tool such as peeler . It is advisable to wash the cassava with clean water before 
peeling to reduce the microbial load. Ensure that the peels including rinds (inedible part) 
are completely removed. Peels (including rinds) are known to contain very high 
concentrations of cyanoge nic glycosides , which can be toxic.  The peel of bitter cassava 
variety was shown to contain an average  of 650 ppm and the pulp  of 310 ppm total 
cyanide.  For sweet varieties , total cyanide was  200 ppm and 38 ppm for peel and pulp , 
respectively. Peeling the refore, can effectively  reduce the cyanide content by at least 
50%.  
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
6 
 d. Washing : This is done  manually using clean water or mechanically using stainless steel 
equipment such as washer to remove the dirt, and other contaminants  and reduce the 
microbial  load.  
e. Grating: This is done manually by rubbing the peeled cassava roots against the stainless 
sheet with perforations or mechanically using stainless steel e quipment such as grater 
(please refers  to Annex 1 ). During grating, the cyanogenic glycosides are hydrol yzed by 
the enzyme, linamarase.  
f. Dewatering : This is done manually by placing the g rated cassava in food grade sacks  or 
any clean suitable food grade  container  and pressed or squeezed by putting weights on 
the container or mechanically using stainless steel equipment such as hydraulic press  
(please refer to Annex 2 ). 
g. Cooling/Chilling/Freezing :  This is  done to prolong the shelf life of grated cassava . 
h. Drying : This is done through solar  drying  by drying  the grated cassava in any clean 
suitable surface or using hygienic mechanical drying equipment  (please refer to Annex 
3) in a dust -free environment , protected from animals like insects, birds, and other 
contaminants . Drying  is done  to reduce the MC of grated cassava to at most 14% MC . 
Dried grated cassava should be  clean, free from extraneous matter , and can be safely 
stored for  a long period.   
i. Sieving /Sifting : This is done manually by straining  the grated cassava  using a clean sieve r 
to remove the large lumps and fiber s to obtain a homogeneous product  or mechanically 
using stainless steel equipment such as sifter.  
j. Packing : This is done manually by fillin g in containers , which will safeguard the hygienic, 
nutritional, technological and organoleptic qualities of the product or mechanic ally using 
stainless steel packing machine. The containers , including the packaging material , shall 
be made of substances , which are safe and suitable for the intended product. They 
should not impart any toxic substance or undesirable odor, flavor to the p roduct. When 
the product is packaged in sacks, these must be clean, sturdy and strongly sewn or 
sealed.  
k. Labe ling: In addition to the requirement s of the Code x General Standard for the Labe ling 
of Prepackaged Foods (CODEX STAN 1 -1985), the following specific provisions apply: a.) 
Nature of Produ ce – Each package , shall be labe led as to the name of the product  and 
type (sweet  or bitter ) or may be labeled as to the name of variety and b.) Non -Retail 
Containers – Information for non -retail containers , shall be given on the container or in 
accompanying documents except that the name of the product, lot identification , and 
the name and address of the manufacturer or packer , shall appear on the container. 
However, lot identification and the name and address of the manufacturer or packer 
may be replaced by an identification mark, provided that such a mark is clearly  
identifiable with the accompanying documents.   
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
7 
 l. Storing:  Storing of grated cassava should be at room temperature, dry, well -ventilated, 
and insect -and rodent -free store/enclosure.  
 
Dried Cassava Chips  and Granules  
 
13. Dried c assava chips  and granules  are derived from clean, fresh , and healthy  cassava. The 
production of dried cassava chips  and granules involve selection,  cleaning, chipping /slicing , 
granulat ing, drying, packing, labe ling and storing . 
 
a. Selection : Select the fresh and healthy cassava roots from the lots for processing of 
cassava. Preferably the selected cassava roots are sweet type and 8 - 12 months old.  
b. Cleaning: This is done manually to remove the soil and other foreign materials in the 
skin so as not to contaminate the produce.  
c. Chipping/slicing : This is done manually using clean s tainless knives or mechanically 
stainless steel equipment such as chipper . Chipping/slicing of ca ssava root should be 
done thinly  i.e. less than 10 mm thick for efficient, fast and adequate drying.  
d. Granulating : This is done  manually by continuous  circular hand stirring movement or 
mechanically using stainless steel equipment such as granulator  (please refer to Annex 
4) to produce round and smooth particles.  
e. Drying : This is done through solar  drying by drying the  cassava  chips and granules  in any 
suitable clean surface or using hygienic mechanical drying equipment in a dust -free 
environment, protected from animals like insects, birds, and other contaminants. Drying 
is done  to reduce th e MC of chips and granules to at most 14% MC . Dried cassava chips 
and granules  should be  clean, having a white color, free from extraneous matter , and 
can be saf ely stored for  a long period.  Total cyanide content of cassava chips could be 
decreased by only 10 -30 %.  
f. Packing:  This is done manually by  filling  in containers which will safeguard the hygienic, 
nutritional, technological and organoleptic qualities  of the  product or mechanically using 
stainless steel packing machine. The containers , including the packaging material , shall 
be made of substances , which are safe and suitable for the intended product. They 
should not impart any toxic substance or undesirable o dor, flavor to the product. When 
the product is packaged in sacks, these must be clean, sturdy and strongly sewn or 
sealed.  
g. Labeling:  In addition to the requirements of the Codex General Standard for the Labe ling 
of Prepackaged Foods (CODEX STAN 1 -1985), the following specific provisions apply: a.) 
Nature of Prod uce – Each package shall be labe led as to the name of the product and 
type (sweet  or bitter ) or may be labeled as to the name of variety and b.) Non -Retail 
Containers – Information for non -retail c ontainers , shall be given on the container or in  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
8 
 accompanying documents except that the name of the product, lot identification and 
the name and address of the manufacturer or packer shall appear on the container. 
However, lot identification and the name a nd address of the manufacturer or packer 
may be replaced by an identification mark, provided that such a mark is clearly 
identifiable with the accompanying documents.  
h. Storing:  Storing of cassava chips and granules should be at room temperature, dry, well -
ventilated, and insect -and rodent -free store/enclosure.  
 
Cassava Chips  
  
14. Dried cassava chips used as snack food can  be made from extruded flour or from dried 
cassava chips.  The production process involves  selection, cleaning, peeling, slicing,  
frying/heating, packing, label ing and storing.  
 
a. Selection:  Select the fresh and healthy cassava roots from the lots for processing of 
cassava. Preferably the selected cassava roots are sweet type and 8 - 12 months old.  
b. Cleaning: This is done manually to r emove the soil and other foreign materials in the 
skin so as not to contaminate the produce.  
c. Peeling : This is done manually with clean stainless knives or mechanically using stainless 
steel tool such as peeler. It is advisable to wash the cassava with clean water before 
peeling to reduce the microbial load. Ensure that the peels , including rinds (inedible 
part) are completely removed. Peels (including rinds) are known to contain very high 
concentrations of cyanogenic glycosides , which can be toxic.  The peel of bitter cassava 
variety was shown to contain an average of 650 ppm and the pulp  of 310 ppm total 
cyanide.  For sweet varieties, total cyanide was 200 ppm and 38 ppm for peel and pulp , 
respectively. Peeling therefore, can effectively reduce the cyani de content by at least 
50%.  
d. Chipping/ Slicing : This is done manually using clean stainless knives or mechanically 
stainless steel equipment such as chipper. Chipping/slicing of cassava root shoul d be 
done thinly  i.e. less than 2 mm thick for efficient, fast  and adequate cooking . 
e. Frying or Heating of Sliced Cassava Chips Up to Temperatures Above 180°C : The 
surface dries out, sealing the water content inside.  
f. Packing:  This is done manually by filling  in containers which will safeguard the hygienic, 
nutritional, technological , and organoleptic qualities of the product or mechanically 
using stainless steel packing machine. The containers , including the packaging material 
shall be made of substances , which are safe and suitable for the intended product. They 
should not impart any toxic substance or undesirable odor, flavor to the product. When 
the product is packaged in sacks, these must be clean, sturdy and strongly sewn or  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
9 
 sealed.  
g. Labeling:  In addition to the requirements of the Code x General Standard for the Labe ling 
of Prepackaged Foods (CODEX STAN 1 -1985), the following specific provisions apply: a.) 
Nature of Produ ce – Each package , shall be labe led as to the name of the product and 
type (sweet  or bi tter) or may be labeled as to the name of variety and b.) Non -Retail 
Containers – Information for non -retail containers , shall be given on the container or in 
accompanying documents except that the name of the product, lot identification and 
the name and a ddress of the manufacturer or packer , shall appear on the container. 
However, lot identification and the name and address of the manufacturer or packer 
may be replaced by an identification mark, provided that such a mark is clearly 
identifiable with the ac companying documents.  
h. Storing:  Storing of cassava chips should be at room temperature, dry, well -ventilated, 
and insect -and rodent -free store/enclosure.  
 
Cassava Flour  
 
15. Cassava f lour can be used in various food applications . 
 
a. Selection:  Select the fresh and healthy cassava roots from the lots for processing of 
cassava. Preferably the selected cassava roots are sweet type and 8 - 12 months old . 
b. Cleaning: This is done manually to remove the soil and other foreign materials in the 
skin so as not to contaminate the produce.  
c. Peeling: This is done manually with clean stainless knives or mechanically using stainless 
steel tool such as peeler. It is advisable to wash  the cassava  with clean water before 
peeling to reduce the microbial load. Ensur e that the peels , including rinds (inedible 
part) are completely removed. Peels (including rinds) are known to contain very high 
concentrations of cyanogenic glycosides , which can be toxic.  The peel of bitter cassava 
variety was shown to contain an average  of 650 ppm and the pulp of 310 ppm total 
cyanide.  For sweet varieties, total cyanide was 200 ppm and 38 ppm for peel and pulp , 
respectively. Peeling therefore, can effectively reduce the cyanide content by at least 
50%.  
d. Washing: This is done manually usi ng clean water or mechanically using stainless steel 
equipment , such as washer to remove the dirt and other contaminants and reduce the 
microbial load.  
e. Grating : This is done manually by rubbing the peeled cassava roots against the stainless 
sheet with perf orations or mechanically using stainless steel equipment such as grater. 
During grating, the cyanogenic glycosides are hydrolyzed by the enzyme, linamarase.  
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
10 
 f. Dewatering:  This is done manually by placing the grated cassava in food grade sacks or 
any clean suitable food grade container and pressed or squeezed by putting weights on 
the container or mechanically using stainless steel equipment such as hydraulic press.  
g. Drying: This is done through solar  drying by drying the grated cassava in any suitable 
clean surface or using hygienic mechanical drying equipment in a dust -free environment , 
protected from animals like insects, birds, and other contaminants. Drying is done  to 
reduce the MC of cassava flour  to at most 14%.  
h. Milling/ Pulv erizing : This is done mechanically using stainless steel equipment such as 
miller to produce approximately 80 mesh of the final form.  
i. Packing:  This is done manually by filling  in containers which will safeguard the hygienic, 
nutritional, technological and organolepti c qualities of the product or mechanically using 
stainless steel packing machine. The containers , including the packaging material shall 
be made of substances , which are safe and suitable for the intended product. They 
should not impart any toxic substance  or undesirable odor, flavor to the product. When 
the product is packaged in sacks, these must be clean, sturdy and strongly sewn or 
sealed.  
j. Labeling:  In addition to the requirements of the Code x General Standard for the Labe ling 
of Prepackaged Foods (CODE X STAN 1 -1985), the following specific provisions apply: a.) 
Nature of Produce – Each package  shall be labe led as to the name of the product and 
type (sweet  or bitter ) or may be labeled as to the name of variety and b.) Non -Retail 
Containers – Information for non -retail containers shall be given on the container or in 
accompanying documents except that the name of the product, lot identification , and 
the name and address of the manufacturer or packer , shall appear on the container. 
However, lot identificati on and the name and address of the manufacturer or packer 
may be replaced by an identification mark, provided that such a mark is clearly 
identifiable with the accompanying documents.  
k. Storing:  Storing of cassava flour should be at room temperature, dry, we ll-ventilated, 
and insect -and rodent -free store/enclosure.  
 
Cassava Starch  
 
16. Cassava starch  is commonly used in food manufacturi ng as a thickener,  emulsifier  and can 
also be used as raw materials of glues, plywood , and papers.  
 
a. Selection:  Select the fresh and healthy cassava roots from the lots for processing of 
cassava. Preferably the selected cassava roots are sweet type and 8 - 12 months old.  
b. Cleaning:  This is done manually to remove the soil and other foreign materials in the 
skin so a s not to contaminate the produce.   
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
11 
 c. Peeling: This is done manually using clean stainless knives or mechanically using 
stainless steel tool such as peeler to avoid the production of ferrocyanide , which gives 
bluish color to the starch  if non -stainless  tool is used . It is advisable to wash the cassava 
with clean water before peeling to reduce the microbial load. Ensure that the peels , 
including rinds (inedible part) are completely removed. Peels (including rinds) are known 
to contain very high concentrations of  cyanogenic glycosides , which can be toxic.  The 
peel of bitter cassava variety was shown to contain an average of 650 ppm and the pulp 
of 310 ppm total cyanide.  For sweet varieties, total cyanide was 200 ppm and 38 ppm 
for peel and pulp , respectively. Peeling therefore, can effectively reduce the cyanide 
content by at least 50%.  
d. Washing : This is done manually using clean water or mechanically using stainless steel 
equipment such as washer to remove the dirt and other contaminants and redu ce the 
microbial load.  
e. Rasping or P ulping : This is done  manually  by slicing the roots and then rasping, grating 
or crushing them, which tears the flesh into a fine pulp.  The cell walls are torn up and 
the whole of the root is turned into mass in which the  greater part, but not all, of the 
starch granules is released.  
f. Screening and W ashing : starch is separated from the  cellulose fibers using the jet 
extractor or the continuous perfor ated -basket centrifuge and is  done in three stages.   
g. Settling and purification : This includes the whole series of operations for separating the 
pure starch from soluble contaminants.  
h. Drying : This is done to remove  free water from the sediment obtained in settling tanks 
on flour tables or from the concentrated slurries pr oduced by separators and purifiers.  
It can be accomplished through sun/oven/mechanical drying.  The starch cake is led 
from the basket centrifuge by a warm conveyor to a pneumatic drier, where the final 
MC is reduced to  at most  14%. 
i. Packing:  This is done manually by filling  in containers which will safeguard the hygienic, 
nutritional, technological and organoleptic qualities of the product or mechanically using 
stainless steel packing machine. The containers , including the packaging material shall 
be made of substances , which are safe and suitable for the intended product. They 
should not impart any toxic substance or undesirable odor, flavor to the product. When 
the product is packaged in sacks, these must be clean, sturdy and strongly sewn o r 
sealed.  
j. Labeling:  In addition to the requirements of the Code x General Standard for the Labe ling 
of Prepackaged Foods (CODEX STAN 1 -1985), the following specific provisions apply: a.) 
Nature of Produ ce – Each package shall be labe led as to the name of th e product and 
type (sweet  or bitter ) or may be labeled as to the name of variety and b.) Non -Retail 
Containers – Information for non -retail containers shall be given on the container or in  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
12 
 accompanying documents except that the name of the product, lot ide ntification and 
the name and address of the manufacturer or packer shall appear on the container. 
However, lot identification and the name and address of the manufacturer or packer 
may be replaced by an identification mark, provided that such a mark is cle arly 
identifiable with the accompanying documents.  
k. Storing:  Storing of cassava chips and granules should be at room temperature, dry, well -
ventilated, and insect -and rodent -free store/enclosure.  
 
V. Recom mended Practices based on Good Agricultural Practices  (GAP)  
 
Planting  
 
17. Cultivars of cassava should be carefully selected from reputable source s such as DA -Regional 
Outreach Station (ROS) . Choose var ieties with low cyanide content ( please refer to 
PNS/BAFPS 119:2013).   When bitter cassava varieties are used, a dequate processing is 
essential to reduce the HCN content.  
 
18. Plant cassava during the start of rainy season or when there is sufficient soil moisture 
condition.  
 
Harvesting  
 
19. Harvesting should be done at 7 - 9 months for fresh roots and 8 – 12 months for the 
produ ction of starch. Late harvested cassava roots have shown to have increased in cyanide  
content . 
 
Raw Materials Selection  
 
20. Cassava roots for the preparation of cassava products s hould be processed as soon as 
possible  after harvest.  
 
21. The cassava selected from the lots should be of high quality and incidences of bruises, 
mechanical damage, should be minimized. Spoiled and woody cassava should be discarded . 
 
 
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
13 
 VI. General Recommendations  
 
34. National and local governments such as Department of  Agriculture (DA) , Department of 
Health (D OH), Department of Interior and Local Government (DILG) , Department of 
Science and Technology (DOST) , as well as  Non -Governmental Organizations (NGOs) , 
should be involved in promoting effective cassava cultivation with the introduction of low 
cyanide, high yielding , and well -adapted varieties of cassava and processing methods as a 
means to ensure maximum  reduction of residual cyanogen  in cassava  roots an d its  
products.  
 
35. Producers  of cassava roots and its products should have access to materials with 
information on the specific recommendations based on GMP  and guidance on methods  
for reducing residual cyanogen  in cassava roots and its products.  
 
36. The DA food s afety regulatory agencies, particularly the Bureau of Plant Industry (BPI),  
may consider introducing scientific kits such as picrate kits  or other validated analytical 
methods,  to monitor cyanide concentrations in cassava roots and its products at th e point 
of use.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
14 
 Figure 1. Flowchart for  Processing  of Grated Cassava  
 
 
 
 
 
 
 
 
 
 
 
Selection
Cleaning
Peeling
Washing
Grating
Dewatering
Cooling/Chilling/Freezing
Drying
Sieving/Sifting
Packing
Labelling
Storing
Grated Cassava 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
15 
 Figure 2. Flowchart for P rocessing  of Chips and Granules  
 
 
 
 
 
 
 
Selection
Cleaning
Chipping/Slicing
Granulating
Drying
Packing
Labelling
Storing
Cassava Chips and Granules 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
16 
 Figure 3. Flowchart  for Dried Cassava Chips Used as Snack  
 
 
 
 
 
 
 
Selection
Cleaning
Peeling
Chipping
Frying or Heating
Packing
Labelling
Storing
Dried Cassava Chips Used as Snack 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
17 
 Figure 4. Flowchart for the  Processing  of Cassava  Flour  
 
 
 
 
 
 
 
 
 
 
 
Selection
Cleaning
Peeling
Washing
Grating
Dewatering
Drying
Milling/Pulverizing
Packing
Labelling
Storing
Cassava Flour 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
18 
 Figure 5. Flowchart for Processing  of Cassava Starch  
 
 
 
 
 
 
 
 
 
 
 
Selection
Cleaning
Peeling
Washing
Rasping or Pulping
Sreening andWashing
Settling and Purification
Drying
Packing
Labelling
Storing
Cassava Starch 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
19 
 REFERENCES:  
 
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products 
(CAC/RCP 73 -2013 ). 
 
Codex Standard for Bitter Cassava (Codex Stan 300 -2010).  
 
Codex Standard for Edible Cassava Flour (Codex Stan 176 -1989).  
 
Codex Standard for Gari ( Codex Stan 151-1989).  
 
Codex Standard for Sweet Cassava (Codex Stan 238 -2003).  
 
http://biology -assets.anu.edu.au/hosted_sites/CCDN/papers/cardoso_etal_18_451_460.pdf  
 
https://law.resource.org/pub/eac/ibr/eas.738 .2010.html  
 
http://pubs.acs.org/doi/abs/10.1021/bk -1997 -0662.ch010  
 
http://www.agnet.org/htmlarea_file/library/20110717000859/pt2005016.pdf  
 
http://www.bt.cdc.gov/agent/cyanide/basics/facts.asp  
 
http://www.codexalimentarius.nl/sites/default/files/page_attachtment/REP13_CFe.pdf  
 
http://www.fao.org/docrep/x5415E/x5415e01.htm#TopOfPage  
 
http://www.fao.org/docrep/x5415E/x5415e03.htm#TopOfPage  
 
http://www.fao.org/docrep/009/ae075e/ae075e04.htm  
 
http://www.fao.org/docrep/005/y4358E/y4358e05.htm  
 
http://www.fao.org/docrep/008/y5979e/y5979e03.htm  
 
http://www.fao.org/docrep/x5032e/x5032E01.htm#1. Cassava cultivation  
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
20 
 Philippine National Standard: Dried Cassava Chips and Granules (PNS/BAFPS 29:2009).  
 
Philippine National Standard: Sweet Cassava – Classification and Grading (PNS/BAFPS 
119:2013) . 
 
Report of the Seventh Session of the Codex Committee on Contaminants in Food , 2013 . 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
21 
 Republic of the Philippines  
Department of Agriculture  (DA)  
BUREAU OF AGRICULTURE AND FISHERIES STANDARDS  (BAFS)  
Technical Working Group  
 
Chairperson  
Rodel G. Maghirang, PhD  
University of the Philippines Los Baños (UPLB) – Institute of Plant Breeding (IPB)  
 
Members  
 
Ma. Theresa C. Cerbolles /Fatima Joan S. Ibarreta  Rachel F. Rocafort/Lauro D. Alkuino  
Food and Drug Administration (FDA)    Food Development Center (FDC)  
Department of Health (DOH)     National Food Authority (NFA)   
   
Director Antonio Gerundio/Heycel Reyes   Jocelyn E. Eusebio/Angelito T. C arpio  
AgriPinoy Corn & Cassava Program, DA   Philippine Council for Agriculture, Aquatic , and   
       Natural Resources Research and Development   
       (PCAARRD)  
       Department of Science and Technology (DOST)  
 
Alexander Joel G. Gibe/Nelson C. Santiago   Inez C. Gonzales/Donita K. Simongo  
Philippine Center for Postharvest Development  Northern Philippine Root Crop Research and  
and Mechanization (PHilMech), DA    Training Center (NPRCRTC)  
       Benguet State University (BSU)  
 
Joel H. Lales/Rhea D. Desalesa  
Bureau of Agricultural Research (BAR), DA  
 
Secretariat  
 
Karen Kristine A. Roscom     Lara Vivas -Navarro  
OIC-Executive Director     OIC-Chief Science Research Specialist  
BAFS, DA       Standard Development Division (SDD)  
       BAFS, DA  
Charlie T. Palilio  
Research Assistant I  
BAFS, DA   
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
22 
 Annex  1 
Cassava Grater  
 
 
Photo cou rtesy of  Department of Agriculture, AgriPino y Corn and Cassava Program, 2014  
       
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
23 
 Annex 2  
Cassava Presser  
 
 
Photo cou rtesy of Department of Agriculture, AgriPinoy Corn and Cassava Program, 2014  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
24 
 Annex 3  
Cassava Mechanical Dryer  
 
 
Photo cou rtesy of Department of Agriculture, AgriPinoy Corn and Cassava Program, 2014  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
PHILIPPINE NATIONAL STANDARD  PNS/BAFS____:2015  
Code of Practice for the Reduction of Hydrocyanic Acid (HCN) in Cassava and Cassava Products  
 
25 
 Annex 4  
Cassava Granulator  
 
 
Photo coutesy of Department of Agriculture,  AgriPinoy Corn and Cassava Program, 2014