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Dehydrated veg

1.         Product Description:  Dehydration of vegetables is the process of reducing moisture of vegetables so that micro-organism do not grow and spoil it and the natural qualities are not harmed to any appreciable extent.  Dehydration is carried out in closed chambers by mechanical means under controlled conditions of temperature and humidity in such a way that the product is attractive, tasty and nutritious.  Dehydrated vegetables are considerably less in weight and volume and can be preserved for a long time.  Due to low cost of dehydrated vegetables compared with canned products, a plant which produces these items has a better and wider market.


2.         Rationale: At harvest time, the production volume of many types of vegetables is greater than the consumption volume during harvest.  Consequently the surplus quantity which is perishable cannot be stored to be consumed or sold after harvest.  Faced with this problem producers sell the vegetables for much lower or even at a “throw-away” prices. 


In the Amhara region, these problems are faced by producers of potatoes, onions, tomatoes, and other vegetables and fruits.  Due to lack of culture in dehydration, so much vegetable products are wasted every year in many localities of the region.


3.         Market Potential:-  Dehydration of vegetables is not a common practice, at least on commercial basis, in the Amhara region and the market for dehydrated products has not yet developed.  Because of this, it is difficult to predict the potential market for dehydrated vegetables.  However, if there are markets for undehydrated vegetables (i.e. fresh vegetables) one can safely assume that there will be sufficient market for dehydrated vegetables which has only lost their natural taste.


4.         Raw Material Source: All localities in the Region which produce vegetables especially those which are closer to the main urban areas.


5.         Process and Technology: Vegetables which are suitable for dehydration are onions, potatoes, peas, ginger, garlic, cauliflower, cabbage, beans, carrot, lady fingers, etc.  Vegetables to be dehydrated are graded according to size, stage of freshness, tenderness; and they are washed thoroughly to remove foreign matters.  The vegetables are then peeled to remove upper skin.  The method depends on the types of vegetable being processed.  Potatoes are peeled by abrasive wheels; onions by hand whereas peas are deshelded by pea huller.  Potatoes and other similar vegetables are then sliced in a slicer.  Peas are pricked in a pricking machine.


There are treatments employed to arrest the action of undesirable enzymes present in the fresh vegetables.  All vegetables except onions, ginger and garlic are given this treatment.  This treatment is known as blanching and sulphating.  For blanching vegetables are dipped in boiling water or steam while sulphitation involves the treatment of the vegetable with sodium sulphite or bisulphate.  This treatment increases the storage or shelf life of dried products, improves the color and protects the vitamin content.  The final stage is dehydration and packing.  Depending on the type of vegetable and quantity to be hydrated, various types of driers are used such as tray drier, rotary kiln drier and tunnel drier, etc.  Time and temperature of dehydration depend on the vegetable and it takes 1 to 12 hours to reduce moisture content to below 5 percent.  After drying the vegetables are tested for moisture and sulphur content; and it is packed in moisture proof paper.  Time between unloading from the drier and packing should not be more than half and hour for better results.


Plant and machinery needed include wooden tables with aluminum top, washing tank, slicer, cross flow drier electrically heated with provision for circulating air and controlled with thermostat, balancing tanks with aluminum, baby boiler, cooling tanks, empty can washing machine with sterilizer, heat sealing machine, other miscellaneous equipment such as weighing balances, aluminum utensils and laboratory equipment.



6.         Estimated Investment: For a plat which can dehydrate about 250kg of vegetables per day, the estimated investment will be as follows:

n  Building/Shade 200m2 at Birr 2000/m2       = Birr  400,000

n  Plant and Machinery                                    = Birr 300,000

n  Working Capital                                           = Birr 100,000



7.         Benefits: Stabilizes the market for vegetable products, increases the income of producers, increases the value of the vegetables to be dehydrated, stimulates vegetable production in the region, introduces new skills and technology to the region, crates possibility to export the dehydrated vegetables.


8.         Location: Any urban center where the surrounding has the types of vegetables to be dehydrated.