Last updated on October 28th, 2026 at 06:30 am
Traditional methods of processing cassava turn a perishable, mildly toxic root into foods that families eat every single day. Soaking, pressing, roasting, boiling, and sun-drying each remove cyanogenic compounds, and each method produces a different food on the family table.
I am a 46-year-old Nigerian farmer from Abia State, born into a family that has processed cassava for generations.
Every food in this article is something my household still makes, from akpu and garri to abacha and fresh starch for usi.
Instead of a textbook summary, you will see the days, containers, and steps we actually use at home.
Each method is paired with published research showing how much cyanide it removes and why the order of steps matters.
You will also meet a fried garri snack that, as far as I know, belongs only to my Ngwa people.
Table of Contents
Why Traditional Processing Still Matters
Fresh cassava spoils within days of harvest and contains cyanogenic glycosides, so no root reaches our plates without some form of processing.
Our community moved from bitter to sweet varieties years ago, yet we still process every root carefully before eating.
Our comparison of bitter and sweet cassava types explains how the two differ in taste and toxicity.
A 2019 study in Scientific African measured cyanide elimination of 47 percent for chips, 80 percent for garri, and 91 percent for fufu.
Safety limits are strict, since Codex sets 2 milligrams per kilogram for garri and 10 for cassava flour, as Food Standards Australia New Zealand notes.
The chemistry behind each step is laid out in our explainer on removing cyanide from cassava.
The Core Traditional Methods of Processing Cassava
After peeling and washing, five methods cover almost everything my family makes, and most households in Ngwa follow the same patterns with small variations.
Peeling and Washing: Where Every Method Starts
Almost every cassava food in my home begins with peeling, and we still do it by hand with sharp kitchen knives.
The knife lifts the brown skin and the thick inner rind together, leaving clean white flesh ready for the next step.
Peeling soon after harvest matters, because roots begin deteriorating within two to three days, a 2022 study of Nigerian processors notes.
Akpu is the one exception in our home, since we sometimes soak roots whole and remove the softened skin afterward.
Peeled roots are then washed in clean water to remove soil, sand, and bits of peel that would spoil color and taste.
Practical knife techniques and ways to reduce flesh losses are covered in our guide to peeling cassava the right way.
Water changes, scrubbing, and drainage tips appear in our article on washing and cleaning cassava roots.
Soaking and Fermenting for Fufu (Akpu)
We soak peeled or unpeeled roots in a drum, a big basin, or a bucket, then cover the container and leave it alone.
The roots ferment for three days when the sun is strong, or four days when the weather stays cloudy, because warmth speeds fermentation.
After soaking, the softened roots are mashed and sieved to remove fiber, and the paste is cooked into akpu.
An older study by Professor Oke of the University of Ife called soaking and sun-drying for fufu the most efficient detoxification process, according to ISTRC proceedings.
Regional names and cooking methods for this swallow are compared in our article on what fufu actually is.
Grating, Pressing, and Roasting for Garri
Garri takes three days in our home, starting with harvesting on the first day and peeling on the second.
After peeling, we carry the roots to the big grating machine, because nobody in our family grates garri roots by hand.
The grated mash goes into a sack and stays under the presser for a full day while the liquid drains out.
On the third day, we bring the sack down, break up the half-dry lumps, and pass them through a local basket-like mesh.
Finally, the sieved mash is roasted in a wide, open pot until it dries into crisp, separate granules.
Oke reported that garri fried with palm oil usually contained no detectable cyanide, while garri fried without it held 5 to 20 parts per million.
Our full garri production guide covers yellow and white garri, roasting tips, and storage in much more detail.
A Fried Snack From Garri Mash
While making garri, my people also set aside some of the sieved, pressed mash before roasting begins.
We mold that mash into balls, soak them in red palm oil seasoned with pepper and salt, then fry them in palm oil.
The balls come out hard and crispy, and as far as I know, this snack is peculiar to the Ngwa people of Igboland.
Other ways of using fresh grated roots in snacks and dishes appear in our article on cooking with grated cassava.
Boiling, Slicing, and Sun-Drying for Abacha
Abacha needs no fermentation, so we harvest, peel, and boil the roots until they are about half done.
After cooling, we slice them into big pieces or fine shreds, using a knife or a mechanical slicer.
The slices soak in water overnight and are then spread under the sun until they dry completely.
Boiling helps on its own, because Oke found 15 minutes of boiling removed over 90 percent of free cyanide from chips.
Soaking does even more, cutting cyanide in chips from 108.2 to 2.9 parts per million after five days in his tests.
Settling Starch for Usi
To make starch, we grate the roots and pour the mash through a sieve so the fibrous pulp stays behind.
The milky water rests until the starch settles at the bottom, and then we pour off the water carefully.
The wet starch is dried in an oven, blended, sieved finely, and stored for buyers who cook it into usi.
That full home method, with photos and drying notes, is in our walkthrough of making tapioca starch at home.
Drying Chips for Flour
For flour, we peel the roots, cut them into small cubes, and dry the pieces thoroughly before grinding.
The dried cubes are ground in a blender or taken to the grater, then sieved into fine, white flour.
Drying alone removes free cyanide more readily than bound cyanide, since Oke recorded losses of about 83 percent and under 30 percent, respectively.
That gap explains why soaking or fermenting before drying, as in lafun, produces safer flour from bitter varieties.
Both approaches, plus the fermented route, are compared in our hub on how cassava flour is produced.
How the Steps Work Together
No single traditional step removes all the cyanide, which is why our methods combine several of them in sequence.
Oke concluded that sequential soaking, sun-drying, and cooking will virtually remove all the cyanide from cassava.
Akpu combines soaking and cooking, garri combines fermentation in the sack with hot roasting, and abacha combines boiling, soaking, and drying.
Variations on sun, shade, and kiln drying are explained further in our guide to cassava drying techniques.
The Limits of Doing It by Hand
Traditional processing demands heavy labor, and a government case study published through FAO contrasted cassava’s low field labor with its high processing labor.
Weather also decides timing, which is why our akpu can need an extra day whenever the sky stays cloudy.
Quality varies between households, because nobody measures moisture, acidity, or cyanide in a home kitchen or village yard.
Processors can weigh machines against these limits can compare each stage in our guide to modern cassava processing methods.
Conclusion
Traditional methods of processing cassava are more than old habits, because each step removes cyanide and creates a distinct food.
Soaking gives us akpu, pressing and roasting give us garri, and boiling, soaking, and sun-drying give us abacha.
Settling and drying produce starch and flour, while garri mash even becomes a crunchy Ngwa snack.
These methods take real time and hard labor, yet they keep families fed and safe.
Try one method at home, and share your own family’s cassava traditions with Cassava Pathway through WhatsApp, X, or this website.
Frequently Asked Questions
What are the traditional methods of processing cassava?
They include soaking for akpu, pressing and roasting for garri, and boiling and sun-drying for abacha. Settling, drying, and fine sieving also produce starch and flour at home.
How long should cassava soak for fufu or akpu?
My family soaks roots for three days in strong sun, four in cloudy weather. Warmth speeds up fermentation, so cooler and cloudier conditions usually need an extra day.
Does abacha need fermentation?
No fermentation is needed, because abacha relies on boiling, overnight soaking, and sun-drying. Boiling removes most free cyanide, and soaking the slices removes much of the remaining cyanide.
Is garri safe to eat?
Well-made garri is generally safe, because pressing, fermentation, and roasting remove most cyanide. Codex limits garri to 2 milligrams per kilogram, so always buy from careful, trusted producers.
Chimeremeze Emeh is a tropical crop farmer and chemical engineer from Ntigha, Isiala Ngwa North LGA, Abia State, Eastern Nigeria, specializing in cassava and palm oil, with over 30 years of hands-on experience growing, harvesting, and processing cassava. He grows TMS series, TME 419, and local traditional varieties on his own farms and operates a small-scale cassava flour and starch production business through Cassava Pathway, which he founded as a CAMA-registered agribusiness in 2024. He is also the founder of Palm Oil Pathway, where he applies the same tropical farming expertise. His farms are located in Ntigha, Abia State.