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Tanzania Groundnuts Deep Processing Industry

Peanut and its Nutrition Values

Peanuts(Arachis hypogaea L.) belong to the legume family and grow underground,

thus referred to as groundnuts. Peanut has high protein content (usually more than

20%) and high oil content (usually more than 40%). It is also a nutritious source of

fats, carbohydrates, Vitamin E and minerals such as calcium, phosphorus, iron, zinc,

magnesium, and potassium. Groundnut can thus help overcome severe nutritional

deficiencies in Tanzania where over 40% of children under five in the rural areas are

malnourished and their development retarded.

Groundnut Production in Tanzania

Commercial groundnut production in Tanzania started in 1946 at Kongwa (Dodoma),

Urambo (Tabora) and Nachingwea (Mtwara) under the Groundnut Scheme. However,

the scheme failed and was subsequently abandoned in 1951.

Currently major groundnuts growing regions include Dodoma, Tabora, Shinyanga,

Singida, Mtwara, and Mwanza. Groundnut is usually intercropped with cereals or

cassava. 11 varieties of groundnuts have been released to date, and Pendo is very

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popular.

Groundnut is grown by smallholder farmers in Tanzania, providing both food and

income for households. Nearly 1 million smallholder farmers grow groundnuts. Most

groundnut farmers grow less than 1 hectare of groundnuts on their farm. Since peanut

is one of the key sources of household nutrients, women are mostly found as paying

more laboring in producing the crop.

In 2013, Tanzania ranked 9th in the world for peanut production, producing 785000

tons of peanuts, which is harvested on an area of 740000 hectares, accounting for

1.7% of global production. However, the yield is still low, producing 1.06 tons per

hectare in 2013, ranked 69th in the world. Reasons for low yields include drought,

diseases and lack of improved varieties.

Export Market of Groundnuts in Tanzania

Groundnuts in Tanzania are exported mainly as shelled nuts. Even though the country

could be among the world’s top 10 groundnut exporters, it receives the lowest price of

the top 20 countries. Export markets are constrained by stringent aflatoxin standards

set by importing countries.

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Farmers do not have incentives nor do they have the ability to grow aflatoxin free

groundnuts.

Peanuts Deep Processing Industry Analysis in Tanzania

Peanuts industry in Tanzania has inadequate value addition and agro-processing

activities. There are a few large groundnut exporters operating in Tanzania, but the

processing part is performed elsewhere, usually in the companies country of origin.

Groundnut is one of the major oilseeds produced in Tanzania. However, there is

virtually no oil produced commercially from groundnut in this country, since

groundnuts in nut form have higher value than converted into oil. It is not economical

to press groundnuts to extract edible oil as there are several cheaper sources such as

sunflower seeds.

Most of the groundnuts are consumed as snacks in the following forms: Raw nuts;

Roasted salted and non salted nuts; Roasted spiced peanuts; Stir fried peanuts mixed

with other foodstuffs. Some groundnuts are ground into powder, which can be done

by a peanut powder grinding machine. Kashata is peanut brittle traditionally sold by

street vendors in Tanzania along with black coffee.

Groundnut processing and shelling

equipment are often Chinese made as

they are often the most inexpensive.

Farmers prefer new technologies

which are simple and tend to avoid

devices that may require frequent

adjustments.

Peanut pods after harvesting should be

dried to a safe moisture level to

prevent the growth of microorganisms,

particularly moulds that produce aflatoxins. Tests were carried out for drying

groundnuts in batch dryers and maximum temperature was 54°C in single layer of

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sacks to reduce moisture content from 48% to 8%. Groundnuts were also dried in tray

dryer and two feet deep freshly harvested pods were dried at air temperature of 38°C

from moisture content of 48% to 8%. Simple twin tray dryers were also used driven

by diesel engine. In continuous flow dryers, temperature of hot air was also

maintained at 38°C.

Freshly harvested peanuts should be cleaned and sorted to remove damaged nuts and

other foreign matter. By using density separators or air legs, light pods can be

removed and slotted screens are used to remove pre-shelled kernels.

At the shelling plant, the peanuts undergo a sorting process to remove defective

kernels. Blanching used together with gravity tables and manual or electronic sorting

is very efficient in removing aflatoxin-contaminated kernels. Color sorting combined

with blanching can reduce 90% aflatoxin contamination.

Tanzania Peanut Butter

Production

Peanut butter is traditionally

used for cooking purposes in

many homes in rural Tanzania.

It is used in preparation of

side dishes and is also cooked

with vegetables, pearled

sorghum and maize. Commercially produced peanut butter is used as a spread on

bread especially by the urban middle classes. Tanzania groundnuts can make good

paste.

Peanut butter can be produced in the following steps:

1. Cleaning of peanut kernels

Shelled peanuts are cleaned by winnowing and blowing away the light particles and

removing broken and infested nuts by hand.

2. Roasting

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In this step, adequate heat is required to ensure cooking of the nuts, while uniform

roasting should be achieved. This step may take 10 to 30 minutes to obtain uniform

golden coloured (light brown to brown) nuts.

3. Cooling

The roasted nuts are cooled before going to the next step.

4. Peeling and sorting

Peanuts after roasting have brittle skin and can be removed easily. Roasted peanut

peeling machine is recommended for this process. Two rotating rollers in the peeling

chamber remove the red coat, which is then sucked by air fan. The peeling rate can be

98%. After peeling, burnt nuts and other nuts with undesirable qualities are removed.

5. Grinding

There exist different types of peanut butter taking smoothness into consideration. In

Tanzania, a finely ground, smooth paste is preferred. The kernels are ground in peanut

butter machie or in a hand operated plate mill which is available in the local market.

6. Mixing

In this step, ground paste is mixed with other ingredients such as vegetable oil, sugar,

salt and stabilizer. Vegetable oil such as corn, sunflower or groundnut is heated to

80–90°C and added with a quantity of 2-5% to improve the spreadability. Some

manufacturers add 6% of sugar or maltose and 1.7% salt to improve the flavor. Peanut

stabilizer is added at a quantity of 2–3% to reduce oil-meal separation. The paste is

then heated to about 80°C to ensure that the stabilizer melts and is well blended into

the paste.

7. Filling

The butter is filled hot into containers that have been cleaned and sterilized.

Full-automatic filling machine is recommended for this process, which features

automatic bottle loading, filling and discharging.