MANUFACTURE OF COCONUT SUGAR AS A COTTAGE INDUSTRY

by

Atih Suryati Herman*

Summary

Indonesia has the largest coconut planta4ion in the world. At present coconut is the 2 n most important commodity after rice. Coconut production has been increasing due to the increase of the area of its plantation. The increase of coconut production is in contradiction with the decrease of the demand for coconut due to the increase in supply of palm oil. The situation is even worse for coconut farmers because of the decrease of the price of coconut products in the world market. They suffer from losses every year.

Coconut farmers and estates seek for alternatives to diversify their product to eliminate their loss. Coconut sugar, which has a good local and export market, is chosen by most of them. Some researchers and observers reported that the income of a coconut farmer is roughly 5 times higher if they tap the influorescense for sugar production compared to fruiting it. Few big estates have already started to process coconut sap for sugar using a system of business sharing with the processors.

This successful effort brings to a significant increase of coconut sugar production. The sugar is mostly marketed locally, while its export has just started but still in small quantity.

The paper explains in detail the processing of coconut sugar as a cottage industry in Indonesia, including the need for raw material, equipment, labour and process, as well as uses and quality of the finished product. It explains also the future development of coconut sugar industry in Indonesia, especially the pattern of business share which is most likely to be used by coconut estates owners and coconut sugar processors.

INTRODUCTION

Coconut has a very important role in life an economic welfare of Indonesian people. It is the 2ng most important commodity after rice. Statistical data show that Indonesia has the largest area of coconut plantation in the world (3,317 hectares). In terms of production it is still the second biggest after the Philippines (SOEBIAPRADJA in TARIGANS and AIAHAIUD, 1991).

The biggest part, that is 97% of coconut plantation in Indonesia, belongs to small farmers who still apply a very traditional technology so that the production per hectare is low. Number of small farmers involved is about 3 million. In the mean time, big estates that own 3% of coconut plantation absorb 954,402 laborers.

------* Head, Food Science Division, Institute for R & D of Agro-Based Industry, Department of Industry, Bogor, Indonesia. The area of coconut plantation within the last 20 years has been growing as much as 4.86% per year. The private big estates have the biggest growth rate (38.18% per year), followed by government-owned estates (13.16% per year), and small farmer (4.61% per year). The growth increased the production of coconut in Indonesia.

Ninety percent of coconut production is consumed by household, oil industries and food industries. In the last few years, the demand for coconut in the country has been decreasing due to the increase in supply of palm oil. This situation is even worse because of the decrease of the price of coconut products in the world market. Coconut farmers and estates suffer from losses every year.

The above conditions made every entrepreneurs involved in coconut production seek for other alternative to diversify their product. One of the most popular product, believed to have good prospect is coconut sugar.

Sugar derived from palm trees is well known all over Indonesia for centuries. The product is not refined but brown sugar which is prepared in a traditional manner. Twenty-six out of the 27 provinces in Indonesia produce brown sugar which amounted to 789,475.94 tonnes in 1985, as shown in Figure 1. The palm trees used are Cocos nucifera, Arenga pinnat, Borassus flabeliver, and Nipa fructicans. Since coconut (Cocos nucifera) has already been commercially cultivated while the other three have not, coconut sugar has dominated palm sugar production, at 54% f total brown sugar production (Dit. Gen. of Small-Scale Industries).

Government of Indonesia gives a very big attention to small-cottage-industries for their development. It is expected that these cottage industries play an important role in improving welfares of rural communities by providing more employment opportunities. Big industries should assist them in any aspects including assistance in finance, technology, equipment and marketing. Firms owned by government must use 5% of their profit to assist small industries.

Above policy of the government encouragres coconut farmers to develop coconut sugar processing. Efforts of big firms in assisting coconut sugar processor to market their product, leads to a bigger market of coconut sugar locally as well as for export.

USES OF COCONUT SUGAR

Coconut sugar used to only be produced in various shape and size of mould. Started in 1984, the Institute for Research and Development of Agro-Based Industry (IRDABI) conducted research and development to diversify the product in order to increase the value of final product. It was found that granule form can improve the practical use of the sugar and extent of market. Simple technology of crystalization was introduced to the centres of brown sugar home industries since 1986, and at present, the product is already commercially produced.

It is estimated that the supply of coconut sugar in Indonesia at present is less than its demand. Coconut sugar is marketed locally for household, street food processors, restaurants, and local food industries for preparation of various types of traditional food. The per capita consumption of brown sugar in Indonesia is around 5 kgs or almost 30% of total sugar consumption.

Food industries which use coconut sugar as part of their main raw material are those of soy-sauce and "dodol", very popular Indonesian traditional food which are also export commodities. In the latest years, new food industries also absorb coconut sugar in a significant quantity. These are industries of confectioneries, bread, biscuits, cookies, cakes and extrusion snack food. Coconut sugar is also used in colouring and flavouring ice creams.

Rapid development of food industries brought about to the significant increase in coconut sugar demand in local markets. In 1985, the industrial sector absorbed 36.2% of brown sugar production. Soy-sauce was the biggest user, at 63.6% of brown sugar used by industries.

It was also reported that some countries, including the Middle East, Australia, New Zealand, USA and Europe, have an average demand of 1,000 tonnes per month (Department of Industry in SUDARISYANTO, 1991). This figure seems to increase due to preference of customers in developed countries for healthy foods. Coconut sugar which contains proper amount of minerals is very attractive to them.

PROCESSING OF COCONUT SUGAR

Coconut sugar is made mainly by home industries in coconut-producing villages.

RAW MATERIAL

Tapping and Correcting of Coconut Sap

Coconut sugar is prepared from fresh coconut sap. The sap is obtained by tapping the influorescence (spadix) of the coconut palm tree. Tall variety coconut tree starts to bear fruit after reaching 8 years while the hybrid does after 4 years. They keep bearing up to 50 and 40 years for tall and hybrid variety respectively, then they need to be renovated.

The spadix, when mature but before it opens up, is selected for tapping. The number of spadices on any tree at. anytime will be 2 or 3. Tapping can be started if the tree has already 3 spadices, when the length of the youngest spadix is 20 cm. minimum. Tapping should be done from two oldest spadices. The third one can be tapped when another new spadix has come out and have a length of 20 cm. When suitable for tapping, the spadix will be about 60 cm long. By this technique, the coconut tree can produce sap continuously for almost one year.

Before tapping is started, the spadix has to be opened by removing the spathe carefully using a sharp knife. The opened spadix is then wrapped with coconut leaves, and then is gradually bent downward carefully. The tip is tied down with string to a nearby leaf branch.

Three to five days later, the tip is untied and cut open by thin slicing (+ 2 mm thick) using a very sharp knife. The slicing is done every morning and afternoon within 3 days.

Receiving the coconut sap is started on the 4th day. A 3 litre receptacle made of a thick section of a bamboo is tied to the spadix stem. End of the spadix is put into the receptacle so that the sap comes into it.

Sap is collected twice a day, before 8 a.m and after 4 p.m. The tapper has to climb the tree carrying an empty receptacle to replace the filled one, which is brought down. The capacity of a tapper per day is 25-30 trees for 10-15 m height of trees, and 30-40 trees for less than 10 m height, of trees.

One spadix can be tapped for 1 to 1.5 months. Two spadices in one tree can be tapped at the same time. Each tree (tall variety) can produce 2-3 litres of sap per day depending on season, age of tree, fertilizer used, etc.

Preservation of the Sap

Coconut sap is very perishable. It could start to deteriorate as soon as it flows out of the spadix due to fermentation by microflora (yeast) which converts the sucrose into invert sugar and furthermore to ethyl alcohol and acetic acid.

The most important prevention of this deterioration is by keeping equipment used in tapping clean. The knife has to be sharp and clean. Receptacles have to be washed in clean water carefully using bamboo brush, put upside down to ooze the washing water through, and dried by holding it round on an open fire. A tapper should have receptacle three times the number of coconut trees to be tapped in order to maintain the availability of clean receptacle.

To preserve sap during tapping, various techniques are used. In almost every place in Indonesia, farmers use special leaves or bark believed to have preservation effect. Leaves of "ginggihiang" (Leea aeguat LINN), manggis (Garcinia mangostana LINN), and "Sulatri" (Calophyllum soulatri BURM), and wood chip of jackfruit ~-Artocarpus integra MERR) are commonly used for this purpose.

In some places, lime is used. One to two spoonful of saturated lime solution or 1. 5 g dry lime is put into each 3-liter capacity receptacle before using for tapping. In few places, especially those located near big cities, 5 spoonful of 0.1-0.2% solution of sodium meta-bisulphite is used instead of lime.

Sap has to be cooked immediately after it is collected. Since sugar preparation is only done in the morning, the afternoon collected sap is boiled and stored to be cooked together with the next morning's collection.

Composition of Sap

Sugar (sucrose) is a major component of fresh coconut sap as shown in the table below.

Table 1. Composition of Fresh Coconut Sap ------Ia) IIa) IIIb) ------Moisture % 87.78 88.40 84.2 Sugar % 10.88 10.37 14.35 Protein % 0.21 0.41 0.1 Minerals % 0.37 0.38 0.66 Fat % - - 0.02 ------a) ITOH et al (1984) b) SAGALA in SARDJONO and DACHIAN, 1986.

The acidity of fresh sap is neutral to slightly acid. The pH is 6.0-6.5 if natural preservative (special leaf, wood or bark) is used, and 7.5 if lime is used as preservative during tapping. Acids in coconut sap is mainly organic acids. ITOH et al (1984) reported that organic acids contained in fresh coconut sap are citric, tartaric, malic, succinic, lactic, fumaric, and pyroglutamic at 22.0, 0.6, 3.6, 73.0, 6.5, 0.1, and 41.0 mg/100g, respectively.

To get good quality sugar, degradation of sucrose in the sap has to be prevented by avoiding fermentation as explained formerly. By fermentation, sucrose is converted into glucose and fructose, resulting in the increase in lactic acid content, hence the increase in acidity. The presence of glucose and fructose complicates the crystalization process.

Cost of Raw Material

It is not easy to calculate the cost of raw materials since small scale coconut sugar processors commonly do not keep records. These small scale processors can be classified into three groups, namely:

1. Processors who tap their own trees; 2. Processors; who rent coconut trees to be tapped: and 3. Processors who work in coconut estates and who usually are paid by getting a percentage share in sales.

Cost for renting coconut trees is Rp 150- ' 000 ' (US$ 75) per 37 trees per year. From this number of trees, 30 trees are tapped and 7 trees are kept as stock. Average production is 90 liters of sap per day. Materials needed for l month to process 90 liters of sap per day are 2 kg of lime (Rp 2.000 or US$ l ~ ), jackfruit wood chip (Rp 500 or US$0.25), and firewood (Rp 10,000 or U$5.00).

EQUIPMENT

Equipment used for coconut sugar processing are tapping knife, receptacle, collection vessel, sieve, pan, furnace, stirring device, mould and table.

1. Tappin knife is, a broad blade razor made, from cast iron or steel. Its cost is about Rp. 10,000 (US$ 5).

2. Receptacle is a thick section of a bamboo with 10 cm diameter and 45 cm length. Bamboo grows abundantly in almost every place, hence receptacle is cheap, around Rp. 150 (US$ 0.07) each.

3. Collection vessel could be bamboo which is, bigger than the receptacle (usually 14 cm in diameter and 65 cm in length), or plastic container. Collection bamboo costs around Rp. 250 (US$ 0.13) while a plastic container (30 liter capacity) costs Rp. 3,000 (US$ 1.5).

4. Sieve is made, from bamboo with diameter of 30-40 cm; when used, a muslin cloth is put on to it to filter out leaves or bark. In some places, plastic sieve is used. The price of sieve, including filtering cloth, is Rp. 500 (US$ 0.25) per unit.

5. Pan of 75 cm diameter and 25 cm deep is used to evaporate the sap. This pan can be made from cast iron or steel. The price of each pan is Rp.45,000 (US$ 23).

6. Furnace is made from bricks or earth with various designs, from a very simple, to a modified one. Figure 2 shows examples of furnace designs. Furnace costs Rp. 25,000 to Rp. 200,000 (US$ 13 -US$ 100). (Figure 2 & Figure 2b).

7. Stirring device. Three types of stirring devices are used in sugar processing. The first stirrer (figure 3) is used to stir the sap during evaporation. The second stirrer (figure 4) is used to cool the viscous mass of concentrated sap prior to pouring into the mould (the finished product is moulded sugar). The third stirrer (figure 5) is used in continuous stirring to crystallize the sugar (the finished product is crystal or granulated sugar). The price of the stirrer is around Rp 1,000 (US$ 0.50).

8. Mould can be made from wood, small bamboo vesels (5-10 cm diameter and 5 cm height), or coconut shell. The price is around Rp 5,000 (US$ 2.5) per 100 moulds.

9. Table is used for placing filled moulds. Wood table, (1 m costs Rp 20,000 (US$ 10).

10. Building for processing may be of non-permanent or semi-permanent construction (25 m2). Cost is around Rp. 625,000 (US$ 312).

Number of equipment needed by coconut sugar processor is shown in Table 2.

Table. 2. Equipment for coconut sugar processing ------Name of equipment Number of equipment Live Span Model 1a) Model 2b) (years) ------Tapping knife 1 2 3 Receptacle and collection vessel 120 480 2 Sieve 1 6 1 P a n 1 3 5 Furnace 1 3 5 Stirring device 3 6 2 Mould 30 60 2 Table 1 3 5 Building for processing 1 1 5 (it is more- (special over not a spe- building, cial. building, 25 m 2 but the kitchen of their home)

a) Model l is for independent farmer/processor to process 90 liters of sap (15 kg of sugar) per day. b) Model 2 is for small industries to process 400 liters of sap (68 kg of sugar) per day.

LABOUR

Coconut sugar processing is generally done by a family. The husband does the tapping and collection of the sap as well as selling the product, while the wife does the cooking. One couple can run a unit of processing with capacity of 90 liters of sap per day.

Coconut sugar business involves quite a number of people. As an example, in Serang Region, West Jawa, there are 507 units of coconut sugar processing involving, 1090 labours (Figure 6).

50 U, 50 L Collector Trader

Coconut sugar 5 U, 5 L Consumer Processor Local 507 U, 1,014L retailer

Big Trader Industrial user 7 U, 21 L Retailer in Big cities

Figure 6. Trading of coconut sugar in Serang Region, and number of labour engaged (Regional Project Management Unit of West Java, 1986) In the latest years, few big estates have started to develop coconut sugar processing. They absorb 4-6 labours per hectare of coconut trees (100 trees).

Description of Process

The processing of sap into sugar is conducted once a day. The afternoon-collected sap is immediately boiled and evaporated until 2/3 the original volume, to be mixed together with the morning-collected sap for further processing. Filtering is always done prior to cooking to filter out the leaves, bark, and other solid foreign matter.

Sap is evaporated by intensive heating. In some places in West Java, the sap is mixed with extract of jackfruit wood chip which is prepared by soaking 20g of wood in 1 liter of clean water. To get a good colour of sugar (brownish-yellow) 1 liter of extract is added to 30 liters of sap.

During evaporation, stirring has to be done occasionally. Foam formed in the surface has to be discarded using a wood spoon. To avoid the excess foam, small amount of coconut oil is added to the sap, 1 spoon or about 2 grams for every 25 liters.

Evaporation is sufficient if the sap is concentrated enough, manifested in appearance of small bursts on the surface. The sap has to be stirred continuously and the fire has to be reduced. When it becomes hard if sprinkled into cold water, the pan is removed from the fire on to a wooden table. Cool it slowly for 10 minutes by slow continuous stirring.

To make moulded sugar, the thick liquid of sugar is spooned into wet moulds. To make granulated sugar, the stirring has to be done slowly first and more intensive after the crystals start to form. Towards the end of this operation, there is simultaneous crystallization throughout the entire contents, giving rise to regular shaped small crystals.

Sugar is cooled down at room temperature and then packed in plastic bags in packs of 1/2-1 kg, depending on the market needs.

Yields

The average yield of granulated sugar is slightly smaller than that of moulded sugar. Ten liters of sap yield around 1.7 kg of moulded sugar (17%) or 1.4 kg of granulated sugar (14%).

QUALITY OF COCONUT SUGAR

Coconut sugar produced in Indonesia should fulfill the quality standard laid down by the Department of Industry, Republic of Indonesia, as shown in the Table 3.

Table 3. Standard of palm sugar, specification (Indonesian Industrial Standard, Revision, 1990)

------Requirement No. Testing criteria Unit Moulded Crystals mg/kg Sugar granules ------1. Visual performance: 1.1.Form normal normal 1.2.Test and normal normal flavour specific specific 1.3.Colour brownish- brownish yellow yellow to to brown brown c

2. Water insoluble max 1.0 max 0.2 solid %, W/W

3. Moisture %, w/w max 10.0 max 3.0

4. A s h %, w/w max 2.0 max 2.0

5. Reducing sugar %, w/w max 10.0 max 6.0

6. Total sugar, as saccharose %, w/w max 77.0 max 90.0

7. Heavy metals: 7. 1. Lead (Pb) mg/kg max 2.0 max 2.0 7.2. Copper (Cu. mg/kg max 2.0 max 2.0 7.3. Zinc (Zn) mg/kg max 40.0 max 40.0 7.4. Tin (Sn) mg/kg max 40.0 max 40.0 7.5. Mercury (Hg) mg/kg max 0.03 max 0.03

8. Arsen (AS) mg/kg max 1.0 max 1.0 ------

The above standard used is the minimum standard. Standard grades in trading depends on the agreement between seller and buyer. They usually have 5 grades, namely Super, SP, One, Two, and PS. Super is the highest quality while PS is the lowest.

COST-BENEFIT ANALYSIS OF SUGAR PRODUCTION

From the economic point of view, producing sugar is more profitable compared to producing coconut or copra. Following analysis is a rough cost-benefit calculation for 3 models of coconut sugar processing industry/unit, using prices in West Java in April 1991. It is shown that for an estate producing coconut sugar, loss from producing coconut or copra (Model A) can be eliminated. Meanwhile, for small farmers (small holders), producing coconut sugar will increase their income up to as much as five times compared to producing coconut (Model B and C).

MODEL A

This is for a hybrid coconut estate. Number of trees is 110 per hectare.

1. Influorescences are tapped for sugar.

Sugar production per hectare is:

110 (trees) x 30 (days) x 2 (times of sap collection) x 2 (bunches of flower per tree) x 0.4 Giter of sap per collection per tree) x 15% (yield) = 792 kg/month. The cost of producing 1 kg of sugar is Rp. 464.42 (see Table 4). The selling price of sugar is Rp 550/kg. Profit margin amounts to around Rp. 85.58 per kg of sugar or Rp. 67,799.36 per hectare per month.

2. All trees are kept for coconut production.

Production per hectare per month is 550 nuts. The selling price is Rp. 65/nut. Sales per hectare per month = Rp. 35,750. Production cost is Rp. 550 per tree per month or Rp. 60,500 per hectare, hence the loss of Rp. 24,750 per hectare per month.

3. Coconut is processed to yield copra.

Six coconut yields 1 kg of copra. Copra production per hectare is around 91.7 kg per month. The price of copra is Rp. 310 per kg. That gross income from copra production is Rp. 28,416.66 per hectare per month.

Production cost in preparing copra from coconut Rp. 85.29 per k9 or Rp 7,821.09 per hectare. Tot production cost is Rp. 60,500 + Rp 7,821.09 68,321.09.

The estate suffers a loss of Rp 39,904.43 per hectare per month.

Table 4. Calculation of cost for Model A coconut sugar processing unit

Equipment and Price Economic Cost/kg of Operation inputs Life (month) Sugar (Rp)

Housing 1,350,000 60 28.40 Building for Processing and Wooden were- House, 36m2 906,000 60 19.06 Furnace, 3 105,000 60 2.20 Table, 3 60,000 60 1.26 Evaporating pan, 3 135,000 60 2.84 Tapping knife, 3 30,000 36 1.05 Receptacle, 480 120,000 12 12.62 Collection vessel, 3 9,000 12 0.94 Stirring device, 9 9,000 12 0.94 Sieve, 3 1,500 3 0.63 Mould, 12 12,000 24 0.63 Plastic 3,000 - 3.78 Wooden box 8,000 - 10.10 Firewood 30,000 - 37.88 Labour wages 225,000 - 284.09 Supervisor (1 supervisor/8 ha) 100,000 60 15.78 Overhead 42.22

Cost of production per kg of Sugar: 464.42

MODEL B

This is for a small farmer who owns 1 hectare o coconut trees.

1. Thirty trees are tapped for sugar and 70 trees ar kept for coconut production.

Sugar production will be:

30 (trees) x 30 (days) x 2 (times of sa collection) x 2 (bunches of flower per tree) x 0. (liter of sap per collection per tree) x 159 (yield) = 260 kg per month.

Coconut production will be 70 (trees) x 5 (nuts pe tree) = 350 nuts per month.

Cost of producing 1 kg of sugar is Rp. 60.85 (seE Table 5) or Rp. 15,821 per month.

Farmer's gross income per month will be:

(260 x Rp. 550 - Rp. 15,821) + (350 x Rp. 65) Rp. 149,929

2. All trees are kept for coconut production.

Farmer's gross income per month will be: 100 trees x 5 coconut/tree x Rp 65/coconut = Rp 32,500,

Table 5. Calculation of cost for Model B coconut sugar processing unit.

Equipment and Price Economic Cost/kg of Operation inputs (Rp) Life (month) Sugar (Rp)

Furnace 35,000 60 2.24 Table 20,000 60 1.28 Evaporating pan 45,000 60 2.88 Tapping knife 10,000 36 1.07 Receptacle (120) 30,000 12 9.62 Collection vessel 3,000 12 0.96 Stirring device, 3 3,000 12 0.96 Sieve 500 3 0.64 Mould, 4 4,000 24 0.64 Plastic 550 - 2.11 Firewood 10,000 - 38.46

Cost production per kg of sugar: 60.86

MODEL C

This is for a small farmer who owns 37 trees of tall variety coconut.

1. Trees are tapped for sugar.

Sugar production per month will be:

30 (trees) x 30 (days) x 2.5 Giters of sap) x 15% (yield) = 337.5 kg.

Cost production, which was obtained by similar calculation with that of Tabel 7, is around Rp. 59.59 per kg, or Rp 20,111.62 per month.

Farmer's gross income per month will be:

(337.5 x Rp 550) - Rp 20,111.62 = Rp 165,513-38

2. Trees are kept for producing coconut.

Farmer's gross income will be:

37 (trees) x 8 nuts x Rp 100 = Rp 29,600.

FUTURE DEVELOPMENT OF COCONUT SUGAR INDUSTRY IN INDONESIA

In the latest years, many researchers and observers wrote on the economic comparison between producing fruit and sugar for coconut farmers as well as for estate (HARDOYO, 1991, PTP XI, 1919, SUKADARISYANTO, 1990, JATMIKA, 1990, KOMPAS, 1991, HARIYANTO, 1991). All agreed that at present condition, producing coconut sugar is more profitable than producing fruit.

Many estates laid down a policy of not letting coconut production down. Meanwhile, they realized that producing coconut sugar is very profitable. Some of them took decision of using 30% of their trees for sugar production and the rest were used for producing fruit. A successful pattern in producing coconut sugar in an estate is by applying a system of business share with the processor.

The estate owner invites labour to process sugar from their coconut trees. They provide processing facilities and housing for the processors. The processor has the right to 2 parts of produced sugar, which has to be sold to the estate owner. Tables 6 and 7 show their respective obligations in this business activity.

The above system gives benefit to the processor as well as to the estate owner. The processor does not have to own capital to start the activity, while the estate owner can control the processing activities easily to get the product (coconut sugar) in a reasonable quality and quantity. It is most likely that this pattern will be applied in more estates all over the country.

The success of coconut sugar processing in these estates and rapid development of coconut sugar processing by small farmers will significantly increase coconut sugar production in Indonesia in the near future. It is very positive that export of coconut sugar will also significantly increase.

Table 6. Obligation of the estate owner and the sugar processor in providing processing facilities (JATAMIKA, 1991).

------

Processing facilities Processor Estate Owner ------

Coconut tree - v Tapping knife - v Receptacle - v Collection vessel - v Sieve - v Furnace - v P a n - v Stirring device - v Mould - v Table - v Building for processing - v L i m e v - Fire wood v - Packaging materials - v Store house - v ------

Table 7. Obligation of the estate owner and the processor in conducting coconut sugar production activities (JATMIKA, 1991).

------

Activities Processor Estate owner ------

Tapping the sap v - Collecting the sap v - Processing sugar from the sap v - Processing supervision - v Looking after the processing facilities v - Looking after the building - v Packing the sugar - v Storing the sugar - v Marketing the sugar - v ------

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