General

Storage of cassava roots and stems

Introduction

Cassava roots (Manihot esculenta) is a woody perennial shrub and major source of carbohydrate. It can be processed into many products such as cassava flake, cassava flour and starch. Fresh cassava roots are highly perishable under ambient condition, becoming unmarketable in 3 days or less. However with proper handling at least fresh root can be stored for up to 30days.

Storage of cassava is enhanced by packing in most absorbent material which enables for:-

Creation of high humidity
Reduction in temperature
Exclusion of light

Reasons for cassava storage

Land for planting will not be tied down through the system of leaving the roots in the soil due to lack of storage methods.
Cassava roots will not be allowed to remain in the soil longer than necessary since it causes loss in quality and loss due to animal attack.
To prevent attack and spoilage by germs and diseases (micro-organism) in the soil.
To protect cassava from flood and bush burning
To harvest and store cassava when labour is cheap
To store and sell cassava when price and profit are high.

Signs of cassava spoilage

Colour changes inside root
Rotting of roots
Softening of the roots

Causes of cassava spoilage

Damage during harvest and handling (mechanical injury)
Wounds caused by animal (rodent)
Hot and dry weather condition (temperature and humidity effects)

Storage methods for cassava roots

Cassava can be stored in 2 ways

Cassava in saw dust
Cassava in trench

Methods for cassava storage in moist saw dust

Use a suitable container such as wooden boxes, paper cartons and woven basket
They can be of any size depends on the quantity of cassava roots
Drainage holes of about five should be drilled into the bottom of the box and carton
Spread a layer of sawdust at the bottom of the box, paper carton and woven basket
Bury freshly harvested, unbruished cassava roots carry stalk of 5 – 6cm within layer of moist sawdust.
Cover the root with another layer of sawdust.
Repeat the method until the container is almost filled.
Makes the last layer of saw dust to be 3 – 4 inches
Sprinkle water to moisten the entire content of box
By this process cassava roots have been kept for 10 – 12 weeks in acceptable state.

Methods for cassava storage in trench

Harvest cassava carefully without damage but should carry small stalk. Those damaged should be consumed immediately.
Useful method for storing large quantities of cassava
A trench 2 x 1.5 x 1 meter takes about 750
1,000kg of cassava
Dig a trench of about 1m height, with variable length and breadth depending on the quantity of cassava. (In area of low water table).
Pack the cassava tubers into the trench with alternate layer of palm or raffia fronds.
Burry only cassava tubers that are unbruised and carry a stalk
Cover the last layer with clean palm/raffia leaves and soil.
Keep the soil moist by wetting with clean water when top is noticed to be drying
Build a shed of about 2 – 2 ½ meter height over the trench to reduced evaporation.

Storage of stem

Long term storage of cassava stem is not possible because stems dehydrate. Stems can also be attacked by insects and diseases. Cassava stem can be stored for up to 8 weeks.

Methods