GROUNDNUT - Food And Agriculture Organization

GROUNDNUTPost-harvest Operations- Post-harvest Compendium

GROUNDNUT: Post-harvest OperationsOrganization: National Research Centre for Groundnut (ICAR) (www.icar.org.in)Authors: P.C. Nautiyal, Ph.D. (nautiyal@nrcg.guj.nic.in or pnaut@ad1.vsnl.nic.in)Edited by AGSI/FAO: Danilo Mejia, PhD (Technical), Beverly Lewis (Language & Style),Last reviewed: 07/06/2002ContentsPreface. 31. Introduction . 31.1 Economic and social impact of groundnut. 31.2 World trade . 71.3 Primary products . 91.4 Secondary and derived products . 101.5 Requirements for export and quality assurance . 111.6 Consumer preferences . 132. Post-Production Operations . 142.1 Pre-harvest operations . 152.2 Harvesting . 202.3 Threshing . 232.4 Drying . 282.5 Cleaning . 372.6 Packaging . 392.7 Storage . 422.8 Processing . 472.9 Marketing and policies . 753. Overall Losses . 773.1 Pre-harvest losses due to diseases and pests . 773.2 Losses due to weeds . 793.3 Drought and yield losses . 793.4 Losses due to nutrient deficiencies . 793.5 Losses due to peg drying. 793.6 Losses in post-production system . 803.7 Storage losses . 854. Storage Pests . 884.1 Major pests species of stored groundnuts . 884.2 Relative status of major pests species . 914.3 Pest control. 925. Economic and Social Considerations. 955.1 Overview of costs and losses . 965.2 Major problems . 1015.3 Gender aspects . 1065.4 Proposed improvements . 1096. References and Further Readings . 115

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PrefaceGroundnuts especially those produced in the developing countries have been usedtraditionally since the origin of humanity. It is rich in oil and protein and has a high-energyvalue. Developing countries account for nearly 95 percent of world production. Asia accountsfor about 70 percent of this amount where the major producers India and China togetherrepresent over two-thirds of global output. Other important producers are Nigeria, Senegal,Sudan and Argentina. In most of the developing countries kernels are used for oil extraction,food and as an ingredient in confectionery products. Following extraction, the residual cake isprocessed largely for animal feed, but is also used for human consumption. The qualityattributes that are important for end uses of groundnut vary among the developed anddeveloping countries. Groundnuts are mainly processed for oil in several developingcountries. Even though it is a good protein source, the cake obtained after oil extraction is notutilized to the best advantage. Production of aflatoxin due to the invasion of the fungusAspergillus flavus to groundnut pod/kernel is a serious problem in the trade of groundnuts inthe international market, which has seriously hampered the export business of the developingcountries. Therefore, these countries can no longer rely on monoculture in order to supporttheir growing economies.Under current conditions, crop dependency has made producers vulnerable to losses becauseof the lower prices paid for the pods and kernels. It is, therefore, imperative for them todiversify their production and create added value through processing thereby reducing risksand opening new local and export markets. There is a necessity to investigate newopportunities for the use of groundnut as food and confectionery items. Most of thedeveloping countries have poor drying and storage facilities. Under these conditions the seedloses its quality and viability in storage rapidly. The purpose of this publication is to discussthe importance of the post-production system in developing countries and to suggest suitablecuring, drying, storage and processing technologies. Advised methods are especially meantfor the smallholder farmers and the most diversified uses of groundnut in confectioneryitems.1. IntroductionGroundnut, or peanut, is commonly called the poor man's nut. Today it is an importantoilseed and food crop. This plant is native to South America and has never been founduncultivated. The botanical name for groundnut, Arachis hypogaea Linn., is derived from twoGreek words, Arachis meaning a legume and hypogaea meaning below ground, referring tothe formation of pods in the soil. Groundnut is an upright or prostrate annual plant. It isgenerally distributed in the tropical, sub-tropical and warm temperate zones. Ethnologicalstudies of the major Indian tribes of South America document the widespread culture ofgroundnut and provide indirect evidence for its domestication long before the SpanishConquest. When the Spaniards returned to Europe they took groundnuts with them. Latertraders were responsible for spreading the groundnut to Asia and Africa where it is now isgrown between the latitudes 40 N and 40 S (Pattee and Young, 1982).1.1 Economic and social impact of groundnutChina and India together are the world's leading groundnut producers accounting for nearly60 percent of the production and 52 percent of the crop area. India cultivates about 7.74million hectares and produces 7.61 million tonnes of groundnut with the productivity level of991.8 kg ha-1. South Africa is the major producer in Africa, while in Latin America almostone half of the total groundnut produced in that region may be credited to Argentina. AmongGROUNDNUT: Post-harvest OperationsPage 3

the developing countries Egypt has the highest productivity and capacity to producegroundnuts (Table 1).In most of the developing countries, the productivity levels are lower than in the UnitedStates of America, mainly due to a number of production constraints such as i.) thecultivation of the crop on marginal lands under rainfed conditions; ii.) Occurrence of frequentdrought stress due to vagaries of monsoon; and iii.) higher incidence of disease and pestattacks; iv.) low input-use and v.) factors related to socio-economic infrastructure.Table 1. Groundnut (in-shell) area, yield and production in various developingcountries in Africa, Asia and Latin America during the last decade.CountriesArea (000 ha)Yield (t ha-1)Production (000 t)Nigeria1 7981.11 na3 6582.69 737India7 7400.987 609Indonesia6611.701 NDNUT: Post-harvest OperationsPage 4

CountriesArea (000 ha)Yield (t ha-1)Production (000 ia132.228Latin America and .3112Paraguay321.035Source: FAOSTAT, database 1990 to 1998, each figure is average for the period from 1990 to 2000Especially in the developing countries, groundnut has to play an important role both as oiland food crop. For example in India about 10 kg groundnut per capita are available fordomestic consumption. Fat and oil consumption averages less than 5 kg per capita per year. Ithas been estimated that in the year 2000, approximately 34 million Mt of groundnuts wereproduced worldwider of which 15 million Mt were produced in China, 6 million Mt in India,2 million Mt in Nigeria, 1.5 million Mt in United States of America and the rest mostly inother countries. Protein calorie malnutrition (PCM) is a serious problem in the developingworld. It is ironic that PCM exist in areas where most of the groundnut is produced.Assuming the level of production of 34 million Mt of groundnut in year 2000, there would beabout 6.26 million metric tonnes of groundnut proteins (after correcting for the kernel yield).Thus there should be about 2.6 to 2.8 g of groundnut protein available per capita per day inthe world. This translates into approximately 5.5 percent of the total protein requirements ofthe world. The obvious reason for low consumption of groundnut protein in India is that outof 6 million Mt of groundnuts produced every year, 80 percent are utilized for oil extraction,12 percent for seed purpose, 2 percent for export and the remaining for edible purposes. Theprotein rich cake resulting from oil extraction is fed to the animals as protein supplement. Thegroundnut utilization system in India is shown in Figure 1. The system remains more or lesssimilar in most of the developing countries, with the exception of South Africa.Similarly in other developing countries, most of the groundnuts are used for extraction of oilfor domestic consumption and export. For example, Sudan accounted for 17 percent of theworld groundnut export trade. Groundnuts are important component of Nigerian diet andabout 5 percent of the estimated 58.9 g of crude protein available per head per day, iscontributed by groundnut (Abulu, 1978). In most of the developing countries it provideshigh-quality cooking oil and is an important source of protein for both human and animal dietand also provides much needed foreign exchange by exporting the kernels and cake. In theliterature, groundnut role as cash crop is found to completely dominates its role as subsistentfood crop. In spite of groundnut importance to diets in many developing countries and theGROUNDNUT: Post-harvest OperationsPage 5

increasing emphasis on food self-sufficiency, studies on domestic groundnut consumption areespecially non-existent.Figure 1: Groundnut utilization system in India.(Source: Srivastava, 1988)GROUNDNUT: Post-harvest OperationsPage 6

Countries like South Africa, India, China and Egypt have good potential to utilize theopportunity to export groundnuts or groundnut products to the developed countries. They canearn valuable foreign exchange to improve their economic conditions. In the internationalmarket demand for groundnut products is determined by several factors. The primary factorin Africa has been population growth. In Asia, demand has grown due to a combination ofpopulation growth, increase in per capita income and urbanization. Expansion of urban areassignals higher incomes, higher opportunity cost of time and therefore greater demand forconvenience foods. Groundnut production and consumption in the period up to 2010 is likelyto shift progressively more to developing countries. This boost will be seen in all regions withmost rapid growth in Asia. Per capita consumption will grow sharply in Asia, slowly in subSaharan Africa and will decline in Latin America. Utilization will continue to shift awayfrom groundnut oil towards groundnut meal, especially confectionery products (Freeman etal., 1999).1.2 World tradeOver half of the groundnut harvested worldwide is crushed for oil and a substantial quantityof groundnut produced in developing countries is traded in domestic markets. Internationaltrade of groundnuts is mainly in the form of in shell (pods), shelled (kernels) and meal (cake).A large trade of confectionery groundnut is also booming in the international market. Themajor country export groundnut in shell and shelled is shown in the following table (Table 2).Developed countries like UK, Holland, Germany, France, Canada and Japan account for 65percent of world groundnut demand. However, the major suppliers of groundnut are theUnited States of America, China and Argentina. The international price of groundnuts isgenerally decided by the crop size and quality in United States of America. The fortunes forthe Indian groundnut (shelled) export are bright and it may likely to emerge as a majorsupplier of raw and processed groundnut mainly because of its large production base. Theproduction price of groundnut in India is competitive globally. The market price is only 16percent above the producer price. Except for India and United States of America the priceratio is above 40 percent in the leading exporting countries (Rama Rao et al., 2000). ThoughIndia is the largest producer of groundnut in the world, its share in the worldwide ediblegroundnut market is insignificant.GROUNDNUT: Post-harvest OperationsPage 7