1.2. Food security, nutrition and health

1.2.1. Improvements to home processing and storage
1.2.2. Home processing to earn extra family income

Fruits and vegetables provide an abundant, cheap source of fibre and several vitamins and minerals (Table 3). In general, they have the highest nutritional value when eaten fresh, although an exception may be fermented foods, in which the process of fermentation can increase the content of B-vitamins (Table 5).

However, fresh fruits and vegetables have a relatively short life before they begin to decay and if they are to be stored for an extended period, it is necessary to process them by one or more of the various methods that are available. The extent to which preservation is required depends in part on the type of plant material that is being considered. For example, fast-growing parts such as shoots have a short life before rotting, whereas bulbs and tubers can be stored without preservation for much longer at room temperature (25°C) (Table 4).

The extent to which nutrients are lost during processing varies according to both the type of fruit or vegetable and the process that is used. A summary of losses of selected nutrients is shown in Table 5.

The purposes of processing fruits and vegetables in the home may therefore be summarised as follows:

· preservation of seasonal gluts for survival in times of shortage

· provision of cooking ingredients throughout the year

· increase in convenience by having part-prepared foods available when required.

· availability of different foods throughout the year to provide variety and greater nutritional balance in the diet.

Table 3. - Dietary fibre, selected vitamins and minerals in fruits and vegetables compared with some other foods.

Food	Fibre (g/100g)	Carotene (m g/100g)	Thiamine (mg/100g)	Ascorbic acid (Vitamin C) (mg/100g)	Calcium (mg/100g)	Iron (mg/100g)
Soya flour	11.9	-	0.75	0	210	6.9
Wholemeal bread	8.5	0	0.26	0	23	2.5
Boiled rice	2.4	0	0.01	0	1	0.2
Doughnut	-	0	-	-	70	1.9
Whole goats' milk	0	22	0.04	1.5	130	0.04
Yoghurt	0	5	0.05	0.4	180	0.09
Eggs (raw)	0	tr	0.09	0	52	2.0
Beef (raw)	0	tr	0.05	0	7	1.9
Chicken (raw)	0	tr	0.10	0	10	0.7
Green beans (raw)	2.9	400	0.05	20	27	0.8
Green cabbage (boiled)	2.2	500	0.03	25	30	0.5
Carrot (raw)	2.9	12,000	0.06	6	48	0.6
Okra (raw)	1.3	90	0.10	25	70	1.0
Plantain (raw)	5.8	60	0.05	20	7	0.5
Tomato (raw)	1.5	600	0.06	20	13	0.4
Apricot (raw)	2.1	1,500	0.04	7	17	0.4
Banana (raw)	3.4	200	0.04	10	7	0.4
Mango (raw)	1.5	1,200	0.03	30	10	0.5
Orange (raw)	2.0	38	0.08	38	31	0.3
Pineapple (raw)	1.2	60	0.08	25	12	0.4

tr: = trace amount

(Data adapted from: The Composition of Foods, by Paul and Southgate)

Table 4. - Rate of spoilage of different parts of fruit and vegetable plants

Part of plant	Time before spoilage starts (days)
Fast growing shoots	1-2
Leaves	2-3
Stems	5-50
Fruits	10-30
Roots and tubers	15-50
Bulbs	30-100

When the objective of a programme is to improve health and nutritional status by increasing the effectiveness of food processing, it is usually necessary to combine education and training with practical improvements to facilities and equipment. In order for people to learn from each others' experience and to make such interventions cost effective, it is usually necessary for participants to organise themselves into groups. This in itself can be a long and difficult process in some communities, but where groups such as mothers' clubs or farmers' societies already exist, they can be approached to act as a focus for a new programme. In some instances, successful food processing developments for improved nutrition have also been linked to health centres.

Any improvements to facilities and equipment need to be low cost and easily maintained if they are to be used in a sustained way. Whereas the capital cost of a new building or item of processing equipment can be donated, the facility will cease to operate if both funds and responsibility for maintenance are not established at the outset. Many attempts have been made to share the costs of processing by establishing various forms of producer associations or village co-operatives, with varying degrees of success.

One important factor is the degree of trust and willingness to work together that exists in a community. If there is no history of a communal approach to problem solving or implementing a new development, it can take many years to introduce these ideas. However, there are many examples of successful village associations that have been operating for several years and have supported on-going education and training programmes in health and nutrition, together with the establishment of community systems and facilities for crop processing.

1.2.1. Improvements to home processing and storage

Drying
Concentration by boiling
Fermentation
Pickling
Storage

In most cases, simple methods of processing and storage that are based on traditional knowledge have the greatest chance of being successfully introduced. Improvements to existing practices are more likely to succeed than completely new technologies, not only because they are more familiar to people, but also because traditional methods are suited to local environmental conditions, whereas new technologies may not be. A good example of such an approach is improved drying and storage.

Drying

Drying is one of the most accessible and hence the most widespread processing technology. When combined with improved food stores, it can lead to significant improvements in food security in most regions (exceptions being some areas that have a climate in which drying is difficult for the majority of the year without the use of fuel - see Section 2.2.3). Important examples of dried fruits and vegetables are okra, cabbage, spinach, mango slices or leathers, garlic and other flavourings, all of which are stored for use in daily cooking.

Table 5. - Summary of nutrient losses in different types of food processing

Process/product		Loss (%)
		Carotene	Thiamine	Riboflavin	Niacin	Vitamin C	Pantothenic acid	Vitamin B6
Fermentation:
	Grapes/wine			66	66
	Cabbage/pickled			43	33	73	57	19
	Soybean/Tempeh		41	(+817)	(+488)			(+437)
	Soybean/soysauce		(+400)	(+616)	(+667)
Blanching:
	Peas					25
	Broccoli					30
	Green beans					20
Canning/bottling:
	Carrots	0-9	67	38-60	32	75	54	80
	Peas	0-30	75	47	71	67	80	69
	Tomatoes	0	17	25	0	26	30	10
	Peaches	65	49	39	39	56	71	21
	Pears	-	45	45	0	73	69	18
	Pineapple	25	7	30	0	57	12	-
Drying:
	fruits (average for apple, apricot, peach and grape)	6	55	0	10	56	-	-
	Vegetables (average for peas, maize, cabbage and beans)	5	<10	<10	-	-	-	-

(Adapted from: Food Processing Technology by Fellows)

Sun drying is traditionally practised because there is negligible cost in processing and the work of spreading and turning the crop as it dries can be shared among family members, including young children. Some of the reasons why the introduction of solar dryers into village communities has not been widely successful (Section 2.2.3) concern these factors of cost and workload. Even when constructed from locally available materials, the simplest dryer still has a higher cost than sun drying. Additionally, the work involved in loading and carrying trays of fruits and vegetables and removing them regularly to turn and mix the products, is not suitable for children and therefore places an additional workload on the parents, usually the mothers. Furthermore, the possibility of improved quality products and shorter drying times using solar dryers may not be important factors to families who may be satisfied with the existing quality of dried foods and the time and effort required to dry them.

Under such circumstances, a focus on improvements to sun drying is likely to yield greater results. Examples include raising crops off the ground on woven matting or wooden drying frames to reduce contamination by dust, crawling insects or rodents; covering the crop with mosquito netting to reduce damage and contamination from birds and flying insects; cutting the fruits and vegetables into smaller pieces so that they dry faster and blanching vegetables to retain a better colour. Although it is beyond the scope of this book, it may be possible in some programmes to link drying improvements to agricultural developments and the introduction of crop varieties that are better suited to drying than traditional types.

Concentration by boiling

Relatively few fruits and vegetables are preserved in the home by concentration, mainly because of the additional fuel-wood consumption, but important foods in some societies are tomato paste, extracts from wild plants such as baobab fruit, that are used as flavourings, chutneys and syrups made from fruits or saps. The main requirement to improve processing of these products is to control the rate of heating to prevent localised burning of the product, particularly when it has become thickened towards the end of boiling.

Fermentation

Production of fruit wines and beers is possibly the second most common form of home processing after drying, in countries where alcohol consumption is not prohibited by religious beliefs. A wide range of fruits is used, particularly pineapple, melon and pawpaw. In the example below from East Africa, banana is used. It is difficult to produce a clear juice from bananas but the following description by the processor indicates the complexity and degree of skill required to produce a satisfactory product.

'Bananas are harvested when they are not quite ripe and not over-ripe. They are stored in a pit covered with banana leaves for up to 4 days to ripen. If necessary a fire is lit in a small hole leading into the pit to warm the bananas and hasten ripening. The bananas are peeled and placed into a large wooden trough. They are then crushed to a pulp by walking on the fruit. Two grasses, one of which is young elephant grass, are cut to approximately 15 cm long and carefully mixed in the correct proportions. Thin layers are periodically added to the surface as pulping proceeds and the grass becomes mixed into the pulp. This is to finely divide the pulp into small particles and thus release the juice. Only these two grasses are used as they do not add flavour to the juice in the way that other species do'.

Figure 1. - Traditional pulping of bananas to make juice for fermentation (Courtesy of Midway Technology)

'After approximately 30-45 minutes pulping, the mixed grass and pulp is piled on a coarse filter frame, made from wooden poles lashed together over the trough, and juice is pressed out by standing on the pulp. The juice is then collected using a calabash into which a hole is cut in one side and a hollow handle is fitted to the top. Juice is poured through the hollow handle into a second calabash, which is shaped as a runnel and lined with grass to act as a fine filter. The juice, which is cloudy but without particles, is collected in a clean container. It is tasted at this stage and if necessary, adjusted to the correct sugar content by adding water.

The standardised juice is then returned to a clean wooden trough and sorghum is added in the ratio of 2 kg per 20 litres of juice. The trough is covered with banana leaves and also with the residue from pulping to act as insulation and maintain the temperature of fermentation at ambient (22-26°C) for two days. After fermentation, the liquor is strained through the calabash/grass filter into clean containers or bottles and is then ready for drinking. There are no further clarification or pasteurisation stages and the beer is preserved by the alcohol content (3-5%). As a result it has a shelf life of up to four days without refrigeration. The process could be improved and a longer shelf life obtained, if the product was clarified by filtration or sedimentation and pasteurised in the bottles.'

Home preservation of fruits and vegetables by fermentation to produce pickles is especially common in South and Central Asia, but less so in other regions of the world. Examples include pickles from lime, mango, mixed fruit and a range of vegetables, including different types of cabbage. Each local district may have a slightly different set of ingredients or variations in the process and in India for example, there are estimated to be over 700 different types of fermented pickle.

In all cases the prepared fruit or vegetable is mixed with spices and held in a closed container such as glazed pottery, while a natural sequence of bacteria ferment sugars in the raw materials to produce lactic acid. Provided that the raw materials are not heavily infected with moulds and that insects, which can carry yeasts or moulds on their bodies, are kept out of the container, the build up of lactic acid is sufficient to prevent spoilage and the product can be kept for several months while it is being used.

In the following example from Central Asia, pickled cabbage is produced: a 2 cm layer of salt is placed into the bottom of a wide-necked pottery drum or jar. A 5 cm layer of shredded cabbage is placed onto the salt and the jar is then filled using alternating layers of salt and cabbage. It is then sealed with a wooden or cloth bung and allowed to ferment for several weeks. As the water is drawn out of the cabbage, it forms a pickling brine. If the product is not to be used straight away, the cabbage is weighted down with a clean stone to keep it beneath the brine and to prevent it drying out and spoiling. Little improvement can be made to these processes without substantially increasing capital and/or operating costs. They are well suited to local tastes and environmental conditions.

Pickling

There is also a wide range of unfermented pickles produced in Asia. Two examples below describe the production of lime pickle and mixed pickle from South Asia.

Well ripened, but not over-ripe limes are washed, cut into four (but the pieces are not separated), and dipped in a concentrated solution of salt. They are then dried in the sun for several days. Sometimes salt crystals are sprinkled onto the lime while it is drying. Drying is continued until the skin develops a brown colour and the pieces can be broken using the fingers. The product is then packed along with the expelled juice in pottery vessels. The salt removes water from the pieces due to osmosis and some sugar is also removed. As a result, salt-tolerant micro-organisms begin to grow while the product is being dried. These bacteria produce some acid, but mostly generate the characteristic flavour of the product, which has a sour and salty taste and can be kept for several months.

The main raw materials for mixed pickle are green chillies, onion, papaya, and spices. The papaya and onion are peeled and cut into slices. The spices are also washed and then ground. All ingredients are placed in a clean pot and mixed by hand while adding vinegar. The product can be kept in the sealed pot for several months, during which time there is a degree of fermentation which improves the flavour, but it does not contribute to the preservation. Other formulations of mixed pickles use raw materials such as dates, pineapple or mango.

Storage

In many cases, the most serious problems of food security are connected with inadequate food storage practices. For example, dried foods are susceptible to spoilage by mould or to attack by insects and rodents, particularly if they are inadequately dried. Losses during storage can be considerable and when these are cereal losses, they can be life threatening. Traditional storage practices for fruits and vegetables vary widely in different parts of the world, but all use locally available materials, usually at little or no cost. It is not possible in a book of this size to detail these differences, but the general principles of storage are described below, followed by some examples of good practice that may assist in improving storage practices and facilities in other places.

As described above, the main types of processed fruits and vegetables that are stored in the home are dried foods, followed by fermented and pickled foods and concentrated syrups or pastes. The latter groups are each moist foods but they are preserved by raised concentrations of lactic acid, salt or sugar. All that is required for adequate storage is therefore an impervious pot to contain the contents and an airtight and insect or rodent proof seal to prevent contamination or theft. Glazed pottery or glass vessels, with cork or wooden stoppers, sealed with resin or wax are entirely adequate for the expected shelf life of these products. They should be stored off the floor in a cool dark place, away from sunlight and dampness.

Dried fruits and vegetables need protection from insects, animals and from uptake of moisture. Those foods that are required to remain unbroken also need protection from crushing and those that contain high levels of carotene, such as green leafy vegetables or carrots, also require protection against sunlight. Because of their bulkiness, pottery vessels may be too expensive to store an adequate supply and many families resort to hanging dried fruits and vegetables from rafters or over cooking areas, where they are sure to remain dry. This deters most animals but does not provide adequate protection against insects. Improved storage can be achieved by constructing a simple mesh basket from wooden sticks and mosquito netting, which can be hung from the rafters in a cool, dry place, away from sunlight.

Dried foods should not be stored on the floor. If storage on tables or raised platforms in the house is the only option, the supporting legs should rest in small containers of oil or kerosene to deter crawling insects. Storage containers should be protected by insect proof mesh. Ideally, re-used cans, having press-on lids or similar insect- and rodent-proof containers are used, once they have been thoroughly cleaned and dried.

1.2.2. Home processing to earn extra family income

There are very large numbers of people throughout the developing world who process foods in their homes and sell them to neighbours or in local markets, in order to generate a little extra money to supplement family incomes. People in this informal sector are characterised by having little capital to invest in equipment and they are forced to buy inputs such as raw materials, ingredients and packaging in small quantities from retailers, because of a lack of working capital or an uncontrolled cashflow (see Section 2.3.4). This increases the unit costs of their products and may make them un-competitive on price with those from the formal sector, or even in some cases with subsidised imports. They have poor access to credit because they have little or no collateral and credit providers cannot justify the high administrative costs of servicing a large number of small loans.

Figure 2. - Informal sector processing of fruit

It is also frequently the case that informal processors have little experience of quality control and so their products do not compete well on quality, safety or appearance with those from the formal sector. Because they only process fruits or vegetables until they have earned sufficient money for their immediate needs and they then cease production until the next financial need, informal enterprises are unable to build up trusting relationships with suppliers or retailers and as a result, future orders may be more difficult to obtain.

Thus a complex mix of factors need to be addressed when a programme is designed to assist informal, home-based processors. Provision of accessible credit is one component, but by itself is insufficient to generate success. Technical training in production routines, hygiene and quality assurance is also required and most importantly, an improved ability to identify suitable markets and to develop skills in selling the products is needed. The different objectives of a programme of assistance, described in Section I, should be clearly identified when initiating work of this kind.

There are a number of development programmes that are achieving some success in improving the incomes to processors in the informal sector and some of the organisations listed in Appendix IV have experience in this area. It is not usually possible for an individual farmer or rural family to adequately learn all of the skills needed to process and sell fruit and vegetable products in competition with large scale producers. But the formation of groups of people that are able work well together with mutual trust among the members has in some cases been shown to overcome these problems. People learn from each other, are empowered by the group, are able to access credit because of the larger needs of the group and in some cases, are able to achieve savings by bulk purchases of inputs.

The division of labour within the group also has social benefits not only in providing a more flexible working environment to take account of household responsibilities but also in developing, encouraging and rewarding an individual's competence and skills in their area of work. This can have dramatic effects on the confidence and determination of individuals to succeed. This approach also removes the need for each member of the group to have expertise in all areas of operating a processing enterprise (for example checking quality, negotiations with suppliers or customers, keeping records, producing financial data, marketing and selling etc.), and allows each member to develop their own specific contribution to the success of the group, based on their individual skills and abilities. There can be various structures for such groups, including producer co-operatives, in which each member has an equal share, groups based on religious beliefs, extended families or those formed around a different existing activity, such as a youth club, a mothers' union or a village development society.

A further development of group activity in the informal sector is the division of responsibility for different parts of the food supply chain. A number of groups can reach agreement to collaborate and share the profits of the joint venture. In some successful approaches, a farmers' group is responsible for supplying a local group of processors with an agreed amount of raw materials of specified quality. This removes the need for farmers to develop skills in marketing their crops and they can concentrate on their farming abilities. The processors may buy from a number of farmers in the local area, thus reducing transport costs for the raw materials. The processors concentrate on producing high quality products at the lowest cost and sell them to a marketing group. The marketing group may buy from a number of processors and concentrate only on finding the highest paying and most reliable markets for the products.

A development of this system may involve part-processing of fruits or vegetables on the farm to reduce transport costs and to add value to the farmers' produce. For example, fruits can be peeled and part-dried or crystallised on the farm and then transported to a local processor in returnable containers. There are some environmental advantages in doing this because not only are fuel costs for transportation reduced, but also localised pollution at the central processing unit is removed and fruit and vegetable wastes are available on the farm for green manure. In this system, the processor standardises the quality of each batch by blending or sorting and then packages each farmers' products under a single brand name. This gives both benefits of lower costs through bulk purchases of packaging and the ability to supply larger amounts to meet demands of retailers who would otherwise not consider purchasing.

There is thus a spectrum of processing enterprises from a single person working intermittently from home, through various forms of single and group-based informal enterprises to more formal structures. In Part 2 of this book, the detailed aspects of operating formal food processing businesses are described.