Lynne Wong's PhD thesis

ased on the manner in which the Brix-free water determination is performed on the
sample (Mangion and Player, 1991). This is done by adding 150 mL of a 10° Brix sucrose
solution to 8 g of dry sample (here the moist cake is assumed to contain 50% moisture and
hence double this mass is used in the calculation), and measuring the increase of Brix in
the resulting solution. The washing was repeated on the remainder of the sample until all
was free from residual Brix.
To separate pith from the fibre, the cakes from the Pinette Emidecau press were soaked in
a bucket of water. A sieve assembly was mounted with a 2 mm, 1.18 mm and 38 μm sieve
in order on top of each other. A handful of fibre and pith mixture was put onto the top
sieve, and running tap water was used to wash the pith into the bottom sieve. Separation of
pith from the fibre in the sample was thus effected. The separated fibre was hand pressed
and placed in a metal tray for drying in an oven at 65 °C to constant mass. The separated
pith was also dried in the same way.
The dried fibre samples sometimes still contained some pith, and dry sieving by using a
1.18 mm sieve mounted on top of a receiver was used to ensure complete separation.
3.4.3.2 Rind, dry leaves and green leaves
These samples were treated as for the cane stalk. Pre-treatment in a Jeffco cutter-grinder
was necessary, the sample mass and the time of disintegration are indicated in Table 3.4.
Table 3.4. Preparatory treatment process for fibre extraction
from sugar cane plant components.
Sample
Cutter-grinder
Mass used in
the Jeffco wet
disintegrator/g
Disintegration
time/s
Top
Stalk
Rind
Dry leaves
Green leaves
-
400
500
300
100
300
60
30
75
60
30
3.4.3.3 Cane tops
After the cane tops were detached from the stalks at the point where they naturally broke
off the stalks, they were cut into 10 cm lengths and into thin strips lengthwise; in so doing,
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