43 higher moisture content. There is no other way to keep a good Aci from getting
moldy except speedy sun dry in the current processing system. The photographs are showing the operation and the method of processing tapioca Figure 12..
Smashing Sedimentation
Sun Drying By-product: Ampas
Figure 13 Operation and method of processing tapioca
2. Critical Points of Processing Cassava
As shown in Appendix 5, the tripartite processing is carried out to produce tapioca flour engaging with cassava producer, Aci producer, and tapioca producer.
At each processing step, the necessary operation is taken into place starting at the harvest of cassava. In small scale operation and where worker is cheap and
sufficient, harvesting and cleaning of tubers are easily implemented by hand. Peeling of tubers is also accomplished by hand with knife. At cassava producer
steps, all works must be accomplished as faster as possible because of quality
44 deterioration of tuber if the time is taken longer. Thus, the time is a critical point
and tubers must be treated within 24 hours or less. In Aci producer steps, peeled tuber is washed by foot. A good washing of
tuber can cut ash content of the finished product in half. The clean tubers are smashed by hand by use of rasping device driven engine. At this level, the
important factors are rasping magnitude and water quality. A good smashing provides the well rasped pulp to increase the recovery ratio of starch from tubers.
These steps require clean water which is the primary factor to produce a higher quality of tapioca and also shorter time of processing. Such critical points are
summarized in Table 14. Table 15 Critical points of processing cassava in SSTA
Step Operation
Critical Point 1
Washing Tuber is washed be free from dirt, crude
fiber, and cork particles. 2
Peeling Tuber is peeled skin off by hand
3 Washing
Peeled tuber is washed by foot. 1. These three processing must
be done as quickly as possible. 2. If it takes longer time, the
quality is dropped.
4 Smashing
Smashing or rasping is done to destroy cellular structure and rupture the cell wall
to release the starch as discrete. 1. A clean water is a primary
factor to produce good quality of Aci.
2. A good smashing keeps a good recovery and quality.
5 Sieving
Sieving or screening is to separate pulp into two fractions, i.e. waste fibrous
material and starch milk with cloth by hand or with dynamic sieve.
1. A clean water is also a primary factor.
2. Recovery ratio is determined in this processing
step.
6 Sedimentation Sedimentation is to separate the solid
starch from suspension in water for 8 to 12 hours.
1. A clean water is also a primary factor.
7 Pulverizing
Starch cake is pulverized by hand or with wire net plate.
1. Smaller particles by pulverizing provide a shorter
drying time. 8
Sun drying Pulverized starch is exposed to sun for 4
to 6 hours to reduce moisture content from 30-40 to 12-14, a level low
enough for long-term storage. 1. Sunshine place or open field
is a must. 2. Dust is easily flown into Aci
during sun drying. 3. Weather forecast is of
importance on one day before for lotting in the following
day.
9 Pulverizing
after drying Dried starch is pulverized again as
finishing operation by use of wooden spool.
1. This processing is done according to customers
requirement.
45
C. Tapioca Producer
