Lynne Wong's PhD thesis

which ground the material, produced a fine powdery product, with pith and fibre being
macerated into one homogeneous sample. Subsequent Brix-free water determination
showed similar results for the wet disintegrator and Jeffco cutter-grinder materials while
the mechanical grinder material had higher results by five units, which they attributed to
the increased sample surface area per unit mass by the use of the mechanical grinder.
Moodley (1991) reported that cane stalks (2 kg) were cut into 10-15 cm sections, which
were shredded in a Wadell shredder for a period of 15 seconds and then mixed thoroughly.
Water (2600 mL) was added to the crushed cane (400 g), and the sample was further
prepared in a cold digester for two minutes. The material was then transferred to a
fibre-pith separator (Fig 3.5) consisting of a perforated stainless steel plate of 2 mm
diameter holes made into a basket (35 x 15 x 15 cm) submerged in a trough (45 x 39 x
20 cm) filled with water (25 L) and rotated for 20 minutes at 23 rpm by means of an
electric motor. The water containing fibre and pith was filtered through a 1.651 mm screen
to retain the fibre and a 100 micron screen to collect the pith.
Figure 3.5. Fibre-pith separator (Moodley, 1991).
A recent version of a fibre-pith separator was reported by Chinsamy et al. (2004). It
consisted of a sample pot of which the bottom and the lid were made of a perforated plate
of 1.6 mm diameter holes. Prepared shredded cane was placed in the pot, water flowed in
from the bottom of the pot and compressed air was introduced at the top of the pot to
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