Gari

Roots are peeled and washed, then grated to a wet mash. The mash is packed into sacks and pressed — traditionally under weights or a screw press — to squeeze out liquid, and it is left under pressure to ferment for a period while the water drains. Fermentation is spontaneous, driven by the micro-organisms already present, and it develops the sour flavour that defines the product.

The dewatered, fermented cake is broken up and sifted to remove fibre and lumps, then toasted: spread over a hot pan or in a mechanised roaster and stirred continuously while it dries. This final step, sometimes called garification, both drives off the remaining moisture and gelatinises the starch, which is what turns a damp mash into hard, dry, free-flowing granules that will swell when they meet water again. Sieving after toasting sorts the granules by size.

Yellow gari is made by adding red palm oil during toasting, which colours the granules and changes the flavour. It is a distinct product in the market, sold alongside white gari rather than as a variation of it, and the choice between them is regional and personal.

Cassava roots naturally contain cyanogenic glycosides, and adequate processing is required before the root is eaten. The gari sequence is one of the traditional processing routes that achieves this, and its steps are complementary rather than optional extras: grating ruptures the tissue, pressing removes liquid, fermentation acts over time, and toasting applies heat to a thin, constantly moved layer. Shortcuts through any of them are recognised in the producing regions as a problem, which is why the sequence has persisted essentially intact through mechanisation.

Buyers judge gari on granule size and uniformity, colour, the degree of sourness, dryness, and freedom from fibre, grit, and sand — the last of these a persistent complaint where roots were poorly washed or the mash met the ground. Sourness is a preference, not a fault: some markets want a pronounced ferment, others a mild one, and gari is bought accordingly.

• Granule size and uniformity after sifting
• Colour — white gari, or the depth of yellow where palm oil is used
• Degree of sourness from fermentation
• Dryness, since inadequately toasted gari will not keep
• Freedom from fibre, grit, and sand
• Swelling behaviour when water is added

Well-made gari is dry and keeps for months in sealed bags or drums, which is precisely its point. It takes up moisture from humid air and will mould if it is allowed to, so storage is about keeping it dry; storage insects are the other routine concern. Trade is overwhelmingly domestic and regional within West Africa, with an export flow to diaspora markets, and gari is one of the products through which cassava-processing income reaches rural households, much of the work being done at small and medium scale.