A more complete description of construction details may be found in Appendix 1.
20 – 25 square metres of covered space is ample. Suggested layouts are shown in the appendices - a plan for a factory with one pan in appendix 2 and a plan for a 2 pan system in Appendix 3.
A furnace. A furnace is needed to heat water and to boil juice in a heating pan. Several designs are possible, but two are shown. If fuel is plentiful and cheap, or demand for the product is expected to be small, a single pan furnace (Figure 1) will suffice. If fuel is scarce or expensive and demand for the product is expected to be high, a two pan furnace (Figure 2) is recommended in order to utilize the available heat better.
A heating vessel - or two if the two pan furnace is selected. This should be an open dish with a capacity of between 150 and 250 litres, depending on the size of each batch of syrup. A dish 35 cm deep with a bottom diameter of 90 cm and a rim diameter of 110 cm is ideal. There should be handles on the rim so that the dish can be lifted on and off the furnace. The pan should weigh between 10 and 15 kg. A heating vessel is shown in Figure 3.
A foam “chimney”. This may be made of sheet metal or basket work. A chimney should be about three quarters of the diameter of the heating vessel in which it is to be used, and about 50 cm high. Provision should be made to tie it down in the heating vessel. See Figure 3.
Open topped drums. Clean oil drums will do. Depending on the expected demand, between six and ten will be needed. Two should be only 40 cm deep - these two should have handles. See Figure 4.
Equipment for filtering and pressing. See Figures 5 to 11.
Figure 1. A single pan furnace
Figure 2. A two pan furnace
Figure 3 A heating pan with its foam chimney.
In this case the chimney is made of tin plate, but it could equally be made of basketwork.
Figure 4. Drums. Not all of the drums that are needed are shown.
Figure 5 b. Pressing a sack full of seedlings.
Figure 5. Plan and elevation of the filter/pressing station.
(Alternative filtering equipment is shown in figure 10 and alternative pressing equipment is shown in figure 11).
Figure 6. General view of a filter/pressing station with four tanks.
This view shows the internal divisions in the structure, which support the slatted wooden boards (duckboards) shown in Figure 7. The beam across the top and its support (which also holds the beam down when it is being used to press bags of residue) can both be seen. Also visible are the hoses (two in this installation) used to drain the juice that collects inside the retaining walls and the hooks used to hold the end of the hoses above the level of liquid in the tank, in order to stop the flow.
Figure 7. Another view of the flour tank filter/pressing station.
This view shows the duckboards in place.
Figure 8. General view of the filter/pressing station, ready for filtering juice.
Five filter bags can be seen in place, ready for filtering juice. The mouths of the bags are held open by nails sticking out of the top of a rectangular frame 2.6 m × 20 cm (parts of which can be seen resting on top of the cement retaining walls. The bags are resting on the duckboards about 20 cm below their mouths; they are normally laid out across the drained space. The closed ends of two bags can be seen to the left of the beam support.
Figure 9. The pressing operation.
The way the jack is used to squeeze the residue may be seen from this picture. One or two bags full of residue are placed on the duckboard surface. A slatted wooden platen is placed on top of the bag(s) and the jack is then put under the beam and extended. As the pressing from this operation normally contain small particles of solid material, it is best to return this liquor to the beginning of the process - it should be used in sweetwater, in place of water.
Figure 10. Alternative filtering equipment.
A tripod with an open triangular top (Figure 10 a) is used to hold the mouth of the sack in an open position. There are three pins (nails) protruding from the top surface to hold the top of the sack open and to hold it in position. The bottom of the sack rests on a much shorter tripod (Figure 10 b). The triangular top of this second tripod has slots to allow drainage from the bottom of the sack. In order to recover all of the expressed liquid, the two tripods may either be placed in a bowl or placed on a drained surface from which the drained liquid can be collected. Figure 10 c is a sketch of how the tripods are used.
Figure 11. Alternative pressing equipment.
Screw presses such as those shown in Figures 11 a) and b) can be used. Presses of this type are available or can be made in many countries. All the expressed juice should be collected.
A simple but efficient press can also be made from four wooden poles, each about 3 metres long, and a strong ring of metal about 20 cm in diameter. A drained area from which all of the expressed liquid can be collected, will also be needed. The ends of two of the poles are placed inside the ring and the sack is placed between the poles. Weight is then placed on the upper pole (Figure 11c) after which the poles are tied together. Two more poles are similarly placed inside the ring and on either side of the sack (Figure 11d). These poles are also pushed together using any convenient weight, and they are then tied together. Additional pressure can be applied later, as necessary.
The various items needed for carrying out the process are listed. The dimensions shown are approximate. It is best to use hardwood for making the sticks.
|2||sticks for lifting the heating vessel. These sticks should pass through the handles on the heating vessel without difficulty and each one should be strong enough to lift the vessel when it is full. Sticks 7 cm × 2 cm × 2.5 m long should suffice. The ends should be shaped to make them easy to hold.|
|4||metal bowls (approximately 10 litre capacity).|
|2||paddles or stout sticks, for stirring, each about 3 cm × 3 cm × 1.8 m long.|
|1||small shovel, suitable for digging starch.|
|1||a fine screen with an area of approximately 100 cm2 with a 60 cm long handle, for removing scum from the boiling juice. A loop of strong wire covered with muslin and attached to the end of a stick will suffice.|
|4 – 10||natural fibre (e g jute or hessian) cloth sacks for filtering juice.|
|1||sample stick - 2 cm × 2 cm × 0.8 m long.|
|4 – 8||circular basketwork covers to cover drums containing liquids.|
|1||coarse screen for removing debris, such as dead insects. A piece of mosquito netting 50 cm × 50 cm will do.|
|1||long handled ladle for transferring hot liquids. Holes should be made at opposite sides of a metal bowl of about 10 litres capacity, near the rim. Wire should be threaded through these holes and tied tightly round a stick, about 1.8 m long and 2 cm diameter. One should be tied as close as possible to the end of the stick, the other a little way along. In this way, the lower part of the stick is tied across the open top of the bowl, forming a ladle.|
|2||galvanized steel buckets.|
|1||scale for weighing up to 5 kg. Either a spring scale, or a “steel yard” (a “Roman”) scale will do. This is needed for weighing seedlings.|
|1||scale for weighing up to 50 kg. Either a “steel yard” (a “Roman”) scale, or a spring scale will do. This is needed for weighing starch.|
|1||bottle of medicinal iodine solution (for starch tests).|
|2||glass tumblers, for starch tests.|
|1||graduated cylinder, preferably plastic, 100 ml capacity.|
|1||book of pH paper (this is optional).|
|2||thermometer, preferably 0° to 130°C|
|2||Brix hydrometers, 0 to 20o Brix, and 20 – 40o Brix for measuring densities.|
|1||narrow shovel 1.2 m long overall, to remove ash from under the grate.|
|2||pokers (steel rods 0.5 cm diameter, one 2.5 m long, one 1.2 m long).|
|2||steel doors (one sized to close the opening above the grate and the other to close the opening below the grate) - each approximately 20 cm × 20 cm.|
|1||a pestle and mortar for crushing seedlings.|
Drums, barrels, or woven polyethylene sacks, approximately 100 litre capacity (as many as needed for shipping the product).
Polyethylene film bags, approximately 100 litre capacity (liners for the above) with ties.