Lynne Wong's PhD thesis

The level of extraneous matter in cane depends on the weather at harvest, and the
harvesting and loading methods chosen. The loading method known as push-piling
entrains a lot of soil and trash in the cane, and is banned in certain parts of the world.
In his review of cane quality in South Africa, Lionnet (1996) examined the industrial
average of pol % cane (the data became sucrose % cane as from 1981 onwards), fibre %
cane and pol purity of mixed juice from 1960 to 1995, and produced graphs to show the
trend in cane quality received at South African sugar mills over the years. These graphs
have been updated to 2004 (Figs 1.8 and 1.9) by making use of South African published
data from 1960-2004 (Anon., 1985a; Anon., 2002b and Anon., 2005b).
Sucrose % cane and fibre % cane
16
fibre % cane
14
sucrose % cane
12
sucrose / fibre ratio in cane
10
1960 1970 1980 1990 2000
2.5
2.0
1.5
1.0
0.5
Sucrose / fibre ratio in cane
Figure 1.8. Changes in fibre % cane, sucrose % cane and sucrose/fibre
ratio in South African cane from 1960-2004.
91
89
87
Purity of mixed juice
85
83
1960 1965 1970 1975 1980 1985 1990 1995 2000
Figure 1.9. Changes in purity of South African mixed juice from 1960-2004.
16