In Nigeria, cassava production is well-developed as an organized agricultural crop. It has well-established multiplication and processing techniques for food products and cattle feed. There are more than 40 cassava varieties in use. Planting occurs during four planting seasons in the various geo-ecological zones. Cassava is grown throughout the year, making it preferable to the seasonal crops of yam, beans or peas. It displays an exceptional ability to adapt to climate change, with a tolerance to low soil fertility, resistance to drought conditions, pests and diseases, and suitability to store its roots for long periods underground even after they mature. Use of fertilizers is limited, and it is also grown on fallow lands. Harvesting of the roots after planting varies from 6 months to 3 years. The land holding for farming in Nigeria is between 0.5–2.5 hectares (1.2–6.2 acres), with about 90% of producers being small-scale farms. In order to increase production, several varieties of cassava have been developed which are pest resistant; production in the country is hampered with problems with green mite, the cassava mealybug, and the variegated grasshopper.
Cassava, which is rich in starch in the form of carbohydrate, has multiple uses. It is consumed in many processed forms, in the industry and also as livestock feed. Roots or leaves are made into flours. Flours are of three types, yellow garri, white garri, or intermediate colour, with yellow garri considered the best product in Nigeria. Its other products are as dry extraction of starch, glue or adhesives, modified starch in pharmaceutical as dextrines, as processing inputs, as industrial starch for drilling, and processed foods.
Processing of cassava for food involves combinations of fermentation, drying, and cooking. Fermentation is an important method common in most processings. While there are many fermentation techniques for cassava, they can be broadly categorized into solid-state fermentation and submerged fermentation. Solid-state fermentation, typified by garri production, uses grated or sliced cassava pieces that are allowed to ferment while exposed to the natural atmosphere or pressed in a bag. Submerged fermentation involves the soaking of whole peeled, cut and peeled, or unpeeled cassava roots in water for various periods, as typified by the production of fufu and lafun in Nigeria. Traditionally, cassava is fermented for 4 to 6 days in order to effect sufficient detoxification of the roots. Some processors, out of economic pressure, ferment cassava for less than 2 days. Some cases of food poisoning have been attributed to this practice. Application of biotechnology to traditional cassava processing has prospects for producing safe and well-detoxified products.
PROCESSING OF CASSAVA INTO DIFFERENT PRODUCTS
There are many various methods of processing cassava into different product, these are:
1. Processing of cassava into pupuru
2. Processing of cassava into garri
PROCESSING OF CASSAVA INTO PUPURU
Cassava tubers were obtained from a farm. The tubers were peeled. The tubers will be soaked in water which will be fetched in container to enable the easy washing of the cassava by the fifth or sixth day, and this requires abundant water for cleaning. By the time it was washed, and the cassava will be fermented. After fermentation, the water will be drained off by arranging in sacks or jute bags to drain off the water. The sacks and bags are stored or a raised stony platform with some logs place across to further compress the water from the cassava for another four to five days, after which the fermented cassava is moulded into balls ready for drying by the fire.
FLOW CHART OF PROCESSING PUPURU
PROCESSING OF CASSAVA INTO GARRI
To make garri, cassava tubers are peeled, washed and grated or crushed to produce a mash. The mash could be mixed with palm oil (oil garri) before being placed in a porous bag. It is then placed in an adjustable press machine for 1–3 hours to remove excess starchy water. When the cassava has become dry enough, it is ready for the next step. It is then sieved and fried in a large clay frying pot with or without palm oil. The resulting dry granular garri can be stored for long periods. It may be pounded or ground to make a fine flour.
FLOW CHART OF PROCESSING GARRI
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