33 maximum level of sulfites contained in dried fruits and vegetables is 2500 ppm, calculated as
SO
2
. The sample did not meet the requirement, thus it can not choose to be the best sample. The 2
nd
highest total weighted score was found in the sample blanched in 1.0 sodium metabisulfite solution and then dried at 60
⁰C. The sample had total residual sulfites less than 2500 ppm SO
2
, thus it can be inferred that the sample met the criterion of the best sample.
Table 12. Total weighted scores of dried bamboo shoots
[Na
2
S
2
O
5
] T
⁰C 50
60 70
41.41 55.15
52.84 0.5
51.80 54.80
59.93 1.0
47.45 64.63
63.15 1.5
55.63 63.94
70.13 Due to some overlapped standard deviations, the firmness of bamboo shoots may not
be considered to determine the best sample. Referred to Appendix 38, regardless of the firmness of dried and rehydrated bamboo shoots, a similar tendency was observed. The
highest total weighted score was found in the sample blanched in 1.5 sodium metabisulfite solution and then dried at 50
⁰C and followed by the sample blanched in the sample blanched in 1.5 sodium metabisulfite solution and then dried at 60
⁰C and the sample blanched in the sample blanched in 1.0 sodium metabisulfite solution and then dried at 60
⁰C. It was also inferred that the sample blanched in the sample blanched in 1.0 sodium metabisulfite
solution and then dried at 60 ⁰C met the criterion of the best sample, regardless of the
firmness attribute.
4.2.9 Sensory Analysis of The Best Sample of Bamboo Shoot
A rating hedonic test was carried out on October 10
th
2012. Thirty five people including staffs and students of Mae Fah Luang University had been untrained panelists for
the test. Each panelist judged two samples rehydrated-dried bamboo shoots produced at the Food Engineering Laboratory and rehydrated-commercial dried bamboo shoots based on
“like-ability” or their preferences to both samples. Before doing some judgements, the panelists were asked to give some personal info, i.e. name, sex, age, and email address.
Results showed that the panelists consisted of 86.71 of women and the rest of panelists were men. Their age ranged from 20 to 45 years old, as shown in Figure 20. Moreover, they
were also asked to answer three pre-questions about bamboo shoots, as shown in Figure 21, 22, and
23. Almost panelists seldom consume bamboo shoots. They usually consume
bamboo shoots in boiled-fresh form. The other form of bamboo shoots consumed is pickled bamboo shoots. The results also showed that only 2 out of 35 panelists have consumed
rehydrated-dried bamboo shoots.
34
Figure 20. Age of panelists attended sensory test
Figure 21 . Frequency of bamboo shoots consumption
Figure 22. Form of bamboo shoots regularly consumed by panelists
2 4
6 8
10 12
20-25 26-30
30-35 35
F r
e q
u e
n c
y p
e o
p le
Age years
5 10
15 20
25 30
Frequently Seldom
Never F
r e
q u
e n
c y
p e
o p
le
Frequency of consumption
5 10
15 20
25
Stir-fried Boiled
Others F
r e
q u
e n
c y
p e
o p
le
Form of bamboo shoot s
35
Figure 23. Consumption of rehydrated bamboo shoots
Results of a 5-scales of rating hedonic test between rehydrated-dried bamboo shoots produced at the lab and rehydrated-commercial bamboo shoots were shown in Table 13.
There were five sensory attributtes tested, including color, aroma, taste, texture, and overall preference. The results showed that there was highly significant difference p0.01 between
both samples for each attributte. The panelists tended to like the rehydrated-dried bamboo shoots produced at the lab by giving quite high scores, ranged from 3 neither like or dislike
to 4 like moderately, for each attributte, while they tended to neutral the rehydrated- commercial dried bamboo shoots by giving scores ranged from 2 dislike moderately to 3
neither like or dislike. Altough there was no sample that was extremely liked, it can be confirmed that the best sample produced at the lab was more preferable than the commercial
bamboo shoots purchased in Mae Sai Market.
Table 13. Results of a 5-scales of rating hedonic test between rehydrated-dried bamboo
shoots produced at the lab and rehydrated-commercial dried bamboo shoots Sample
Color Aroma
Taste Texture
Overall RBS_Lab
3.71 ± 0.86
a
3.40 ± 0.95
a
3.20 ± 0.81
a
3.37 ± 0.83
a
3.51 ± 0.55
a
RBS_ commercial
2.69 ± 1.05
b
2.60 ± 1.07
b
2.60 ± 1.19
b
2.63 ± 1.65
b
2.69 ± 0.99
b
The same superscript letters in the same colomn for each parameter mean not significantly different p 0.05.
5 10
15 20
25 30
35
Ever Never
F r
e q
u e
n c
y p
e o
p le
V. CONCLUSION AND RECOMMENDATIONS
