Storage and Processing of Roots and Tubers in the Tropics













Table of Contents


Prepared by:
Aliou DIOP, Post-harvest Technologist

Edited by
D.J.B. Calverley, Consultant

January 1998

Food and Agriculture Organization of the United Nations
Agro-industries and Post-Harvest Management Service
Agricultural Support Systems Division

© FAO 1998

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Table of Contents


Chapter 1 - Introduction

1.1 Root and Tuber Crops Production
1.2 The Role of Roots and Tubers in Nutrition
1.3 Consumption Patterns for Roots and Tubers
1.4 General Characteristics of Root and Tuber Crops

1.4.1 Cassava (Manihot esculenta Crantz)
1.4.2 Yams (Dioscorea spp.)
1.4.3 Sweet potato (Ipomoea Batatas L.)
1.4.4 Potato (Solanum tuberosum L.)
1.4.5 The edible aroids

Chapter 2 - Factors Affecting Storability of Roots And Tubers

2.1 Mechanical Damage
2.2 Physiological Factors

2.2.1 Respiration
2.2.2 Transpiration or evaporation of water from tubers
2.2.3 Dormancy and sprouting
2.2.4 Pathological factors
2.2.5 Attacks by pests
2.2.6 Damage by extremes of temperatures

Chapter 3 - Principles of Storage for Roots and Tubers

3.1 Control of Mechanical Damage

3.1.1 Curing of root and tuber crops
3.1.2 Proper packaging and handling

3.2 Control of Temperature
3.3 Control of Sprouting

3.3.1 Storage at low temperatures
3.3.2 Gamma irradiation (Table 3.3)
3.3.3 Chemical sprout inhibitors

3.4 Control of the Spread of Diseases
3.5 Control of Damage Caused by Insects
3.6 Control of Nematodes

Chapter 4 - Handling and storage methods for Fresh Roots and Tubers

4.1 Storage of Fresh Cassava Root

4.1.1 Preparing fresh cassava roots for storage
4.1.2 Traditional storage methods for fresh
4.1.3 Improved low-cost storage methods for fresh cassava
4.1.4 Improved higher cost techniques

4.2 Storage of Yams

4.2.1 Preparing yams for storage
4.2.2 Traditional yam storage methods
4.2.3 Improved low-cost storage methods
4.2.4 Higher cost improved yam stores

4.3 Storage of Potatoes (S. Tuberosum)

4.3.1 Consideration of storage requirements
4.3.2 Preparing ware potatoes for storage
4.3.3 Low-cost ware potato storage
4.3.4 Seed potato storage

4.4 Storage of Sweet Potatoes
4.5 Storage of cocoyams

Chapter 5 - Processing of Roots and Tubers

5.1 Processing Of Cassava

5.1.1 Production of dehydrated chips
5.1.2 The processing of cassava into gari
5.1.3 The processing of cassava into "farinha de mandioca"
5.1.4 The production of cassava bread
5.1.5 The production of attieke

5.2 Processing of other Root and Tuber Crops

5.2.1 Traditional methods
5.2.2 Improved methods of production of dehydrated chips

Appendix One - Approximate nutrient levels of various staple

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

References in the text

References given but not cited in text