Oilseeds and Pulses Introduction

Global production and consumption of oilseeds and pulses continue to grow as their relative importance as sources of energy and proteins in the diets most of the world’s population and as industrial crops continues to grow. Postharvest losses in these subsectors, therefore, represent critical challenges in, especially developing countries including members of IOC, in terms of household food and nutrition security, household farm income, sustained growth in agro-based industry, and capacity to respond to climate change through exploiting alternative plant-based renewable energy sources. This desk-based review examines the scale of postharvest losses in oilseeds and pulses. It covers the following:

 The relative importance of oilseeds and pulses.

 Overview of postharvest losses in the subsectors, including evidence from selected countries.

 Some of the underlying causes of postharvest losses in the subsectors.

 Potential options to reduce postharvest losses in the oilseeds and pulses subsectors.

Global production and consumption of oilseeds and pulses

The bulk of the oil extracted from oilseeds is utilised as food (cooking oil and other processed food products as well as for manufacturing cosmetics, detergents and oleo-chemical products (e.g. paints and lubricants). A sizeable and growing proportion is into producing biofuels. For instance, in Argentina about 64 percent of domestic vegetable oil consumption goes into producing biodiesel, about 50 percent of which is exported. In the European Union about 40 percent of domestic vegetable oil consumption goes into biodiesel production and into direct generation of electricity3_{. By volume, the dominant oilseeds are soybeans and oil palms.}

According to M Boersch (2015), soybeans and oil palm will continue to dominate global oilseed supply beyond 2025. The US and Brazil dominate soybean production whilst Malaysia and Indonesia lead in the supply of palm oil. China is by far the lead importer of oilseeds. Production in the major-producing countries is dominated by commercial farmers whilst processing is concentrated in large-scale processing facilities. In most developing countries, especially in Africa, smallholder farmers lead in production whilst significant share of the processing occurs at small to medium-scale enterprises using basic processing equipment.

Pulses: These are edible legume crops, which are rich in protein, lysine and starch. They

include dry peas, beans, lentils and chick peas which have high levels of dietary fibre and low glycemic index (and therefore important for people with diabetes). Despite these benefits, it is reported that consumption of pulses has seen a slow but steady decline in both developed and developing countries even as consumption of dairy products and meat has increased. Citing data from FAO, Maredia (2012) notes that it is only in Sub Saharan Africa (SSA) that the contribution of pulses to total protein intake is slightly above 10%. In South East Asia the contribution is just under 4% whilst in most developed countries the contribution of pulses to

total protein intake is only 2.5%. Pulses constitute a commodity group which is describe by promoters of Feed the Future as being “uniquely positioned to contribute towards sustainably reducing hunger and poverty whilst simultaneously enhancing nutrition, health and the environment”. Global output of these crops has been around 40 million tonnes per year for the past 10 years and is led by India followed by Canada.

Postharvest losses in oilseeds and pulses

There is a dearth of information and data on the level of postharvest losses in oilseeds and pulses. For instance, the African Postharvest Losses Information System (APHLIS)4 _{provides a}

breadth of data on cereal grains but does not include oilseeds or pulses. A study by the Central Institute of Postharvest Engineering and Technology (CIPHET) in India reported in 2015 that cumulative postharvest losses for oilseeds in general ranges between 3 to 10%5_{. There is every}

likelihood that the overall figures for SSA will be higher considering that the estimates are lower than for cereal grains – 5 to 6% in India in contrast with about 13% for SSA (Hodges et al. 2011). For pulses, Jeswani and Baldev (1990) estimate postharvest losses at very high levels of between 25-50%.

It has to be noted that even the scant data available tends to focus on one form of postharvest losses – that is quantitative or physical losses which can occur as a result of rodent or insect attack or biochemical changes which make the crop hard to cook or process. The losses can also be qualitative – making it difficult to market the commodities unless there is a steep discount reflecting the quality of the grain. A survey of literature on postharvest losses in SSA found that 139 out of 213 (i.e. over 65%) documents reported only losses in the form of edible mass lost or discarded6_{. Only 13.1 percent of the documents reviewed during the study}

reported quality losses. This is despite that fact that there is considerable evidence suggesting that quality losses due, for instance, to infestation by mycotoxins can cause sharp decline in output market prices and may sometimes even lead to loss of access to lucrative export markets for important oilseeds (Nakhumwa C, 2015).

Access to the evidence generated from studies on postharvest losses can also be difficult. Affognon et al. (2014) report that over 57% of the research documents they reviewed were unpublished grey literature held in universities, national research institutions and NGOs in the form of dissertations, conference proceedings and working papers. Incidentally, the reviewers considered only 32.7 percent of the reports as being of good or excellent quality – raising concerns about the quality of evidence generated.

Factors contributing to postharvest losses in oilseeds and pulses

Factors contributing to postharvest losses in the two commodity groups include those listed in Table 9 below.

4 _{APHLIS website (http://www.aphlis.net/?form=home)}

5 _{Jha SN et al. (2015) “Assessment of quantitative harvest and postharvest losses major crops and commodities in India”,} CIPHET, India.

6 _{Affognon et al. (2014) “Unpacking postharvest losses in Sub Saharan Africa: a meta-analysis” World Development Vol. 66} pp.49-68.

Table 9: Causes of postharvest losses of pulses at different stages

Activity/stage Type of loss Contribution to

postharvest loss (%) Harvesting Losses due to shattering and/or attack by rodents, birds and

other pests 4

Threshing Improper threshing and field handling 6

Drying Improper drying leading to moulds 4

Transporting Quantitative losses due late or inefficient transportation 2

Primary processing Poor handling, sorting and packaging 4

Storage Inefficient storage leading to quantitative and quality losses 20

Secondary processing Poor processing practices 60

Source: based on information from Jeswani and Baldev (1990)

Innovations can make a difference in postharvest losses. As indicated above, Affagnon et al. (2014) reviewed 213 postharvest studies in SSA. The countries covered were: Benin, Ghana, Kenya, Malawi, Mozambique and Tanzania. The main oilseed covered was groundnuts and the pulses were cowpeas and common beans. The estimated physical quantitative losses – without and with adoption of loss-reduction technologies are summarised below:

 Oilseeds (e.g. groundnuts): the estimated average annual postharvest loss is 10%. This

estimate does not take account of potential quality-related economic losses. For instance, the level of Aflatoxin infestation in groundnuts in Ghana is estimated by Anim-Somuah et al. (2013) to be over 70%. However, owing the fact that groundnuts produced in Ghana is largely marketed locally this does not affect the crop. However, as reported by Nakhumwa (2015) Malawi lost access to lucrative European markets largely because of high levels of Aflatoxin infestation.

 Pulses (e.g. cowpeas and dry beans): estimated postharvest losses ranges between 14

and 24% by volume. However, this can potentially be reduced to between 2 to 3% if appropriate mitigation strategies are adopted. Coincidentally, postharvest losses for cereals in SSA which can be as high as 26% can be reduced to about 6% with appropriate postharvest handling and technologies.

Loss-reducing pre- and postharvest handling techniques and technologies

Evidence from various sources indicate that adoption of the practices and technologies outlined below can significantly reduce postharvest losses in oilseeds and pulses:

 Pre-harvest practices include planting suitable varieties and at the recommended seed

rates per hectare. For instance, there is evidence from Malawi indicating that most smallholder groundnuts farmers plant at rates of about 47 kilograms per hectare instead of the recommended rate of 80 kilograms per hectare. Consequently, the lower plant population limits natural ground cover by the leaves and therefore increases vulnerability to pests such as Aphids and diseases like Rosette virus disease which lead to losses (Simtowe et al. 2010).

 Harvesting: timing is crucial, especially where unanticipated rainfall during the harvest

season makes field drying of crops difficult. The harvesting technology can also affect level of losses in the field. It can also affect the speed of harvest and therefore the level of losses due to attack by rodents, insects and birds.

 Postharvest drying allows crops to store better. It is important that storage occurs in the

right environment – for instance in well-aerated cribs or on clean surfaces from which livestock are excluded. This will not only reduce quantitative losses but also minimise

quality losses due to contamination with foreign matter. The recommended moisture content prior to storage for major pulses are as follows:

Peas = 16% Green lentils = 14% Chickpeas = 14% Beans = 14% Soybeans = 14%

Where the crop is taken into storage at the moisture levels indicated above, the shelf life can range between 31 to 55 weeks if stored under cool and dry conditions with temperatures around 26o_{C. Appropriate ventilation is necessary to minimise the risk of quality deterioration}

during storage. Fumigation may also be necessary to minimise losses due to pest damage.

2.2.4. Fruits and Vegetables