Lynne Wong's PhD thesis

Table 4.16. Comparison of the Brix-free water of a sample in its original
state with that in a finely divided state.
Sample
Brix-free water in the
original state/%
Mean/%
Brix-free water of
finely cut sample/%
Mean/%
Stalk fibre 1 10.89 10.66
10.54 10.72 10.59 10.62
Stalk fibre 2 11.63 10.26
11.82 11.73 11.34 10.80
Stalk fibre 3 10.57 12.19
10.15 10.36 11.33 11.76
Stalk fibre 4 12.41 12.47
12.82 12.61 13.57 13.02
Stalk fibre 5 14.08 12.76
14.23 14.16 14.21 13.49
Stalk fibre 6 16.97 16.86
16.96 16.96 17.28 17.07
Rind fibre 1 8.57 8.86
8.12 8.34 8.67 8.77
Rind fibre 2 8.38 8.89
8.52 8.45 9.21 9.05
Rind fibre 3 8.51 8.47
8.56 8.54 8.47 8.47
Rind fibre 4 11.53 12.82
12.44 11.98 12.22 12.52
Rind fibre 5 13.89 13.66
14.60 14.24 13.78 13.72
Rind fibre 6 12.66 11.59
12.90 12.78 12.08 11.83
Dry leaf fibre 1 14.96 14.27
14.89 14.93 14.38 14.32
Dry leaf fibre 2 12.77 13.08
13.14 12.96 13.21 13.15
Dry leaf fibre 3 12.92 12.31
12.85 12.89 12.84 12.57
Green leaf fibre 1 13.55 13.63
13.10 13.32 13.03 13.33
Green leaf fibre 2 13.32 12.31
12.87 13.09 12.56 12.44
Green leaf fibre 3 13.58 14.07
13.42 13.50 13.37 13.72
Top fibre 1 14.80 15.39
15.91 15.35 15.72 15.55
Top fibre 2 17.03 15.55
16.13 16.58 15.36 15.46
Top fibre 3 16.07 15.98
15.57 15.82 15.02 15.50
4.4.11 Sample size and precision of the method
In general, the use of 6 g samples and the corresponding 110 g contact solution, with the
ratio of contact solution/sample set at 20, had been adopted for all previous Brix-free water
determinations. However, with pith sample, a test sample of 6 g is very bulky, making it
difficult to dry and handle when filtering after contact with the sucrose solution. The
sample size was therefore reduced to 3.5 g in the above experiment. The filtrate obtained
was found sufficient to satisfy the test volume requirement of Brix measurement as
described in Section 4.4.2.
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