Appendix Two - A comparison of three technologies for the production of gari

Source: ITDG, 1988 Food Technology Source Books: Root Crop Processing

Stage

Traditional Labour intensive

Post-traditional Intermediate

Modern Fully mechanised

Raw Material production and supply

Small holder production
Yield: c. 10 (t/hectare/yr)
From traders

Smallholder production
Yield: c. 10 (t/hectare/yr)
From traders

Factory plantation or smallholder coop.
Yield: 10-25t/hectare/yr From purchasing agents or factory plantations.

Peeling and washing

Manual: 38 kg/pers. hour 25 % raw material loss

Manual: 38kg /pers./ hour; 25% raw material loss

Mechanical abrasive peeler, 30% raw material loss

Size reduction

Manual: 23 kg/ pers. hour
Mechanical: 200kg/hr

Manual: 23 kg/pers. hour
Mechanical: 200 kg/hour

Mechanical: hammer mill (imported), 1500 kg/hr

Fermentation

Fermentation and dewatering in heavily weighted cloth or nylon bags

Batch fermentation in (aluminium) tanks

Batch fermentation in (aluminium) tanks

De-watering

See 4 above

Semi-mechanised: locally made hydraulic or mechanical press

Mechanised: hydraulic press

Screening

Manual: woven fibre screen

Semi-mechanised: locally made screen with hand or mechanically driven paddle

Mechanised: motorised rotary screen

Garification

Manual; cast iron pan over wood fire(combined stage with drying): 2.2 kg/pers. hr

Semi-mechanised: locally made wood burning fryer(combined stage kg/pers. hr with drying): 70 kg/pers. hr

Mechanised: rotary kiln heated by oil burners 450 kg/hr.

Drying

See 7 above

See above

Mechanised rotary drum drier

Milling and sieving

Not necessary
Sieving: locally made

Milling: not required Sieving: vibrating hand or mechanical sieve

Milling: disc mill Sieving: vibrating multideck sieve

Packaging

50 Kg jute sacks

50 kg heat sealed polyethylene bags

50 kg heat sealed polyethylene bags

Material handling (all stages)

Manual

Manual, with trolleys

Belt conveyors, bucket elevators with trolleys

Marketing and distribution

Through traditional gari trade system in local markets

Through traditional trade system and super markets

Through traditional trade system and supermarkets

Purchasers

All income groups, rural and urban

Mainly urban higher income groups and institutions (e.g. school, army)

Mainly urban higher income groups and institutions (e.g. schools, army)

Buildings

600 m

200 m

650 m

Employees per shift total

234

45

28

229

40

9

unskilled

Predominantly female

Predominantly male

Stage	Traditional Labour intensive	Post-traditional Intermediate	Modern Fully mechanised
Raw Material production and supply	Small holder production Yield: c. 10 (t/hectare/yr) From traders	Smallholder production Yield: c. 10 (t/hectare/yr) From traders	Factory plantation or smallholder coop. Yield: 10-25t/hectare/yr From purchasing agents or factory plantations.
Peeling and washing	Manual: 38 kg/pers. hour 25 % raw material loss	Manual: 38kg /pers./ hour; 25% raw material loss	Mechanical abrasive peeler, 30% raw material loss
Size reduction	Manual: 23 kg/ pers. hour Mechanical: 200kg/hr	Manual: 23 kg/pers. hour Mechanical: 200 kg/hour	Mechanical: hammer mill (imported), 1500 kg/hr
Fermentation	Fermentation and dewatering in heavily weighted cloth or nylon bags	Batch fermentation in (aluminium) tanks	Batch fermentation in (aluminium) tanks
De-watering	See 4 above	Semi-mechanised: locally made hydraulic or mechanical press	Mechanised: hydraulic press
Screening	Manual: woven fibre screen	Semi-mechanised: locally made screen with hand or mechanically driven paddle	Mechanised: motorised rotary screen
Garification	Manual; cast iron pan over wood fire(combined stage with drying): 2.2 kg/pers. hr	Semi-mechanised: locally made wood burning fryer(combined stage kg/pers. hr with drying): 70 kg/pers. hr	Mechanised: rotary kiln heated by oil burners 450 kg/hr.
Drying	See 7 above	See above	Mechanised rotary drum drier
Milling and sieving	Not necessary Sieving: locally made	Milling: not required Sieving: vibrating hand or mechanical sieve	Milling: disc mill Sieving: vibrating multideck sieve
Packaging	50 Kg jute sacks	50 kg heat sealed polyethylene bags	50 kg heat sealed polyethylene bags
Material handling (all stages)	Manual	Manual, with trolleys	Belt conveyors, bucket elevators with trolleys
Marketing and distribution	Through traditional gari trade system in local markets	Through traditional trade system and super markets	Through traditional trade system and supermarkets
Purchasers	All income groups, rural and urban	Mainly urban higher income groups and institutions (e.g. school, army)	Mainly urban higher income groups and institutions (e.g. schools, army)
Buildings	600 m	200 m	650 m
Employees per shift total	234	45	28
	229	40	9
unskilled	Predominantly female	Predominantly male