Download - Thesis Chapter IV
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CHAPTER IV
RESULTS AND DISCUSSIONS
4.1 Result of Preliminar Resear!"
The preliminary research was conducted to determine the best gluten
free flour that would be used as the wheat flour replacer in the making of rice bran
brownies. There were four types of flour which were used in the preliminary
research which were cassava flour, rice flour, potato flour and wheat flour. The
subjective and objective test were conducted to analyze the rice bran brownies
which were made using different types of flour. The subjective test that was
conducted was sensory evaluation using hedonic test. The hedonic test was
conducted in order to determine the best wheat flour replacer. There were four
quality parameters of the hedonic test which was observed, which was aroma,
taste, texture and overall acceptance of the rice bran brownies. The objective
analysis was conducted to observe several physical and chemical parameters
which consist of moisture content, water activity and the texture of rice bran
brownies.
4.1.1 Sensor Analsis
The determination of the best gluten free flour was conducted based
on sensory evaluation procedure. The hedonic test was conducted as the sensory
evaluation procedure. According to oskowitzt et al !"##$%, The number of
panelists required for conducting the consumer sensory acceptance tests was '
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(## panelists, therefore in this research, the hedonic test were conducted using )#
panelists. The panelists were untrained panelists and the panelists were asked to
evaluate each of the rice bran brownies samples using a ) points hedonic scale.
The scale was ranged from ( to ), ( stands for extremely dislike and ) stands for
extremely like. The evaluation of each samples were done based on the preference
of the panelists toward each samples. All of data obtained from the hedonic test
were analyzed using the *+ - ( utilizing the one way A/01A.
4.1.1.1 Aroma
Types of 2lour
3."
3.3
3.$
3.4
&
&."
&.3
&.#
&."
3.)$
3.&
5heat 2lour
6assava 2lour
7ice 2lour
-otato 2lour
Aroma was chosen as one of the parameter in the hedonic test to observe the
consumer preference towards the different types of flour used to make the rice
bran brownies.
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&The range of hedonic scaling 8 (;extremely dislike, ";dislike,
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The result of the hedonic test towards the aroma parameter can be
seen in the 2igure 3.(. 2rom the statistical analysis using one way A/01A, from
the A/01A table, it could be seen that there was a significant different between
the types of flour used toward the consumer acceptance of rice bran brownies
aroma. The most preferable rice bran brownies based on aroma parameter was the
rice bran brownies made from cassava flour as shown in the 2igure 3.(. Although
the rice bran brownies made from cassava flour has the highest score in terms of
aroma parameter, from the statistical analysis done using one way A/01A, it was
not significantly different with the consumer acceptance of aroma parameter
toward the rice bran brownies made from rice flour and wheat flour. There was a
research conducted by =atama et al !"##"% about the substitution of wheat flour
with cassava flour in chapatti, in that research, substitution > of wheat flour
with cassava flour still produced chapatti with acceptable aroma. The result of that
research was coherent with the result of this research. *t could be concluded that
the replacement of wheat flour with cassava flour still could produce baked
product, in this case was rice bran brownies, which was still acceptable to
consumers, in terms of aroma parameter. The aroma of rice bran brownies
produced from rice flour was also still acceptable for consumers.
The rice bran brownies made from potato flour gave the lowest score
of the consumer acceptance toward aroma parameter, it was not significantly
different with the rice bran brownies made from rice flour, but it was significant
different with the rice bran brownies made from cassava flour and wheat flour.
+asically the aroma of the rice bran brownies was produced from the rice bran
and the cocoa powder which were used in the formulation. A research was
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conducted by Thybo et al !"##$% regarding several aromatic compounds which
were found in potatoes from several different cultivars. According to +erger
!"##)% approximately compounds contributed to the aroma of raw potato.
+ecause of the existence of such aromatic compounds, it could be inferred that
potato flour would have a distinctive aroma. These aroma compounds could give
changes towards the aroma properties of the rice bran brownies and affect the
consumer preference towards the rice bran brownies aroma.
4.1.1.# Taste
Types of 2lour
#
#.&
(
(.&
"
".&
<
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The result of the hedonic test towards the taste parameter can be seen
in the 2igure 3.". 2rom the result of statistical analysis by one way A/01A, from
the A/01A table, it could be seen that there was a significant different between
the types of flour used toward the consumer acceptance of rice bran brownies
taste. As shown in 2igure 3.", the rice bran brownies which gave the highest score
towards the taste parameter was the rice bran brownies made from wheat flour,
but from the statistical analysis, there was no significant difference between wheat
flour, cassava flour and rice flour toward the sensory acceptance of rice bran
brownies regarding taste parameter. There was a research conducted by ?an et al
!"##)% about the optimization of cassava cake formulation which produce cassava
cake with high consumer acceptance, the research was stated that the baked
cassava cake had a strong cassava flavour. The cassava flavour produced from the
cassava flour during baking could possibly affect the consumer acceptance toward
the taste parameter, although the cassava flavour itself had not beed studied
extensively yet. According to 9ziedzoave !"##$%, high quality cassava flour
should have bland taste without indication of acidity or off flavour, and also
should have the flavour of freshly peeled cassava.
The rice bran brownies made from potato flour was slightly
unacceptable because as shown in the 2igure 3." the mean score for taste
parameter was
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also stated that potato could possible have an off flavour which was correlated
with the non volatiles compounds in the potato.
4.1.1.$ Te%ture
Types of 2lour
#
(
"
<
3
&
$
&.#3.(
3.3$
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flour, but it was not significantly different with rice bran brownies made from
cassava flour. 2rom the 2igure 3.< it could be seen that the mean score given by
the panelist is slightly lower for the rice bran brownies produced from cassava
flour. There was a research conducted by ?an et al !"##)% about the optimization
of cassava cake formulation, in that research the texture parameter of the product
which was firmness was not quite acceptable by the panelists. *t could be assumed
that the cassava flour could affect the texture of the baked product which would
affect the consumer preference of the baked product in terms of texture.
The lowest acceptance in term of texture was given by the rice bran
brownies produced from potato flour. 2rom the result in could be concluded that
potato flour utilization in the making of rice bran brownies might cause a textural
change towards the product which could reduce the textural acceptability of the
rice bran brownies from the consumer.
4.1.1.4 O&erall A!!e'tan!e
The overall acceptance parameter was chosen as one of the parameter
to be evaluated in the hedonic test as its importance to determine the preference of
the consumer towards the rice bran brownies product in terms of combined
evaluation regarding the aroma, taste and texture of the rice bran brownies.
The result of the hedonic test towards the overall parameter can be
seen in the 2igure 3.3. 2rom the result of statistical analysis by one way A/01A,
from the A/01A table, it could be seen that there was a significant different
between the types of flour used toward the consumer acceptance of rice bran
brownies regarding the overall acceptance. As shown in 2igure 3.3, the rice bran
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brownies which gave the highest score towards the overall acceptance parameter
was the rice bran brownies made from
Types of 2lour
#
(
"
<
3
&
$
&.(<3.(
3."(
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2rom 2igure 3.3, the flour which gave the lowest overall acceptance
towards the rice bran brownies was the potato flour, although it was not
significantly different with rice bran brownies made from rice flour. +ased on the
sensory evaluation result utilizing hedonic test, the best gluten free flour which
could be used in the making of rice bran brownies was the cassava flour, because
it still gave product which was acceptable by the consumer and was not
significantly different with rice bran brownies made from wheat flour.
4.1.# P"si!al an( C"emi!al Analsis
4.1.#.1 Te%ture
Types of 2lour
#
(###
"###
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using texture analyzer. The textural parameter which was observed was hardness
parameter. As stated by czcneiak !"##"%, hardness could be defined physically as
force give to attain a given deformation and from sensory perspective hardness
was defined as force require to compress between molar teeth and palate. The
hardness parameter of rice bran brownies made with different types of flour could
be seen in the 2igure 3.&.
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&
2igure 3.& Bardness -arameter of 7ice +ran +rownies
The hardness parameter from rice bran brownies made from different
types of flour was statistically analyzed using one way A/01A, and from the
A/01A table it was resulted that there was a significant difference between rice
bran brownies made from different types of flour towards the hardness parameter.
2rom 2igure 3.& it could be seen that the highest level of hardness was given by
rice bran brownies made using potato flour, and the lowest one was the rice bran
brownies made using rice flour. This result could be correlated with the result
obtained from sensory analysis, in the sensory analysis, the rice bran brownies
made from potato flour had the lowest score in terms of acceptance towards
texture parameter, this could be caused because the rice bran brownies produced
from potato flour had harder texture compared to the others. According to -reedy
!"#((%, potato flour had been utilized to produce flat bread, which was an
unleavened product. The utilization of potato flour in the making of flat bread
could possibly be correlated with its effect toward the hardness of bakery
products. ingh et al !"##&% also stated that potato flour had different size of
starch granules which varied according to its cultivars. -otato flour which has
smaller starch granules would produce harder and more cohesive product, this
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could be an explanation why the rice bran brownies made from potato flour had
higher level of hardness compared to the others.
The low hardness level of rice flour could be caused by the protein
content of rice flour. As stated by uksprasirt !"##(%, rice flour has lower level of
protein compared to wheat flour, therefore the hardness of the rice bran brownies
made from rice flour was lower and significantly different compared to rice bran
brownies made from wheat flour. This was also supported by the theory stated by
Bui et al !"##4% that in the making of cake, flour which has low level of protein
would produce softer texture.
The hardness parameter of rice bran brownies made using wheat flour
and cassava flour was not significantly different and this could be correlated with
the result of the sensory analysis in term of texture parameter. *n the sensory
analysis, the acceptance toward texture parameter of rice bran brownies made
from cassava flour and wheat flour was not significantly different and it could be
assumed that it was not significant different because basically the texture profile
of those two products was not significantly different as resulted from the objective
measurement using texture analyzer.
4.1.#.# )oisture Content
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Types of 2lour #.##>
&.##>
(#.##>
(&.##>
"#.##>
"&.##>
(3.>
().4$>
(.4)>
(
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rice bran brownies made using rice flour, and the lowest one was the rice bran
brownies made using potato flour.
As shown in 2igure 3.$, all of the rice bran brownies made with
different types of flour were significantly different towards each other, prior to
this it could be inferred that each of the rice bran brownies possessed different
characteristics because Bui et al !"##4% stated that the amount of water could
affect the texture and mouth feel of bakery products. The low level of moisture
content given by the rice bran brownies made using potato flour could be
correlated with the result of texture analysis, whereas the hardness of the rice bran
brownies made using potato flour was the least among the others. This assumption
was supported by theory stated by =ilcast !"##3% about the relation between
moisture content and the hardness of food products whereas loss of moisture
could increase the hardness of bakery products. The presence of water is also very
important in baking because it is essentially needed in order to gelatinize the
starch during heating, besides it also plays an important role by interact with
proteins in order to give desirable features for bakery products !Bui et al, "##4%.
The moisture content of rice bran brownies made using rice flour was higher and
significantly different with rice bran brownies made using rice flour, according to
the research conducted by -ark et al !"##"% and /ura !"#((%, the ability of rice
flour to absorb water is higher compared to that in wheat flour.
4.1.#.$ *ater A!ti&it
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Types of 2lour #.$(
#.$"
#.$<
#.$3
#.$&
#.$$
#.$)
#.$4
#.$
#.$$ #.$)
#.$4
#.$<
5heat 2lour
6assava 2lour
7ice 2lour
-otato 2lour
5ater activity was one of the observed parameter in this preliminary, because
water activity was considered as an important parameter to the quality of rice bran
brownies. As stated by Bui et al !"##4%, water activity has a relationship with
moisture content, and furthermore, in bakery products water provides lubrication
when the bakery product is being eaten and affects its texture. This theory also
supported by another theory stated by +arbasoC6anovas !"##)% which stated that
water activity affects the textural properties of foods, foods with high A w have
moist and juicy texture, while foods with lower Aw have harder and tougher
texture. The water activity of rice bran brownies made using different types of
flour could be seen in 2igure 3.).
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&2igure 3.) 5ater Activity of 7ice +ran +rownies
The water activity of rice bran brownies made from different types of
flour was statistically analyzed using one way A/01A, and from the A/01A
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table it was resulted that there was a significant difference between rice bran
brownies made from different types of flour towards its water activity. 2rom
2igure 3.) it could be seen that the highest level of water activity was given by
rice bran brownies made using rice flour, and the lowest one was the rice bran
brownies made using potato flour. As show in 2igure 3.), all of the rice bran
brownies product had water activity value ranged from #.$
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one was the rice bran brownies made using cassava flour. 2rom the statistical
analysis, the consumer acceptance of rice bran brownies made from wheat flour
and rice bran brownies made from cassava flour was not significantly different, so
it could be concluded cassava flour could be used as the wheat flour replacer in
the making of rice bran brownies. This also supported by the result of objective
analysis, whereas the hardness of rice bran brownies made from cassava flour and
wheat flour was not significantly different. 2rom the preliminary research, it could
be concluded that among rice flour, potato flour, and cassava flour, cassava flour
incorporation in rice bran brownies as wheat flour replacer would give the best
characteristic and consumer acceptance, therefore, cassava flour was determined
as the best gluten free flour in the making of rice bran brownies. -rior to the result
of the preliminary result, cassava flour would be used in the making of rice bran
brownies in the main research.
4.# )ain Resear!"
The main research was conducted to determine the best rice bran
concentration and the best baking time in the making of rice bran brownies. The
rice bran brownies was made using cassava flour, which was selected from the
result of the preliminary result. The rice bran concentration which was
incorporated as the substitute for cassava flour consists of five different
concentrations which were #>, (#>, "#>, , and 3#>, while the baking time
was
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was sensory evaluation using hedonic test. The hedonic test was conducted in
order to determine the best rice bran brownies formulation. There were four
quality parameters of the hedonic test which was observed, which was aroma,
taste, texture and overall acceptance of the rice bran brownies. The objective
analysis was conducted to observe several physical and chemical parameters
which consist of moisture content, water activity and the texture of rice bran
brownies.
4.#.1 Sensor Analsis
The determination of the best rice bran concentration and the best
baking time in the making of rice bran brownies was conducted based on sensory
evaluation procedure. The hedonic test was conducted using )# panelists. The
panelists were untrained panelists and the panelists were asked to evaluate each of
the rice bran brownies samples using a ) points hedonic scale. The scale was
ranged from ( to ), ( stands for extremely dislike and ) stands for extremely like.
The evaluation of each samples were done based on the preference of the panelists
toward each samples. All of data obtained from the hedonic test were analyzed
using the *+ - ( utilizing the one way A/01A.
4.#.1.1 Aroma
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7ice +ran 6oncentration3
3."
3.3
3.$
3.4
&
&."
&.3
&.()
3.) 3.3
3.4
3.34
#>
(#>
"#>
3#>
Aroma was chosen as one of the parameter in the hedonic test to observe the
consumer preference towards the different concentration of rice bran and different
baking time incorporated during the making of rice bran brownies.
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&
The range of hedonic scaling 8 (;extremely dislike, ";dislike, rice bran concentration and the lowest acceptance was given by rice bran
brownies made with 3#> rice bran concentration. 2rom 2igure 3.4, it also could
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be seen that there was not a significant different between rice bran brownies made
using #,(#, and "#> rice bran concentration. 7ice bran brownies made using 3#>
of rice bran concentration was significantly different with rice bran brownies
made using #,(#,"# and rice bran concentration.
+aking Time
3.)
3.)&
3.4
3.4&
3.
3.&
&
3.4<
3.)
3.4"
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bran as stated by =aewka !"##%, it also supported by another theory by
ukonthara !"##% which stated that rice bran had several volatiles compound
contributed to its unpleasant aroma.
The result of the effect of baking time toward the consumer
acceptance of aroma could be seen in 2igure 3.4. According to Bui et al !"##4%,
the production of aromatic compounds in bakery products is related to the baking
process, therefore baking time is one of the important consideration which will
determine the quality of bakery products. Bowever, from the statistical analysis
using two factor A/01A, there was no effect of baking time towards the
consumer acceptance of rice bran brownies in terms of aroma, and as shown in
2igure 3.4, there was no significant different of the rice bran brownies made using
different baking time towards the consumer acceptance in term of aroma
parameter.
The result of the interaction of rice bran concentration and baking
time toward the consumer acceptance of aroma could be seen in Table 3.(. 2rom
the statistical analysis using two factor A/01A, there was interaction between
rice bran concentrations and baking time towards the consumer acceptance of rice
bran brownies in terms of aroma, and as shown in Table 3.(, there was significant
different of the rice bran brownies made using different rice bran concentrations
and different baking time towards the consumer acceptance in term of aroma
parameter. The rice bran brownies made using rice bran concentration and
baked for rice
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bran concentration which baked for (#> "#> 3#>
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7ice +ran 6oncentration#
(
"
<
3
&
$
&."3
3.)3.3
3.(
3#>
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&
The range of hedonic scaling 8 (;extremely dislike, ";dislike, rice bran concentration and the lowest
acceptance was given by rice bran brownies made with 3#> rice bran
concentration. 2rom 2igure 3.4, it also could be seen that there was no significant
different between rice bran brownies made using "# and rice bran
concentration. 7ice bran brownies made using 3#> of rice bran concentration was
significantly different with rice bran brownies made using #,(#,"# and rice
bran concentration. 2rom the result, it could be assumed that increasing the rice
bran concentration would reduce the consumer acceptance of rice bran brownies
regarding its taste parameter, this also coherent with the research conducted by
Buang et al !"##&% about the incorporation of rice bran in the pork meatballs. *n
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that research, the increasing of rice bran concentration lowered the consumer
acceptance towards taste parameter. The taste of rice bran brownies product might
be affected by several aromatic compounds contained in rice bran, which has been
studied and characterized by Earunrattanasri !"##3%. Bui et al !"##4% also stated
that there is correlation between aromatic compounds toward sensory perception
of taste. Fuh !((% stated that the dominant flavor characteristics of rice bran are
sweet taste which is attributed to high sugar content in bran and bitter taste which
is attributed to saponins content in rice bran. The decreasing of consumer
acceptance in term of taste parameter as the rice bran concentration increasing
could be affected by the unpleasant flavor given by rice bran prior to the flavor
profile described above.
Baking Time4.25
4.3
4.35
4.4
4.45
4.5
4.55
4.6
4.44
4.54
4.36
35 minutes
45 minutes
55 minutes
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&The range of hedonic scaling 8 (;extremely dislike, ";dislike,
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using two factor A/01A, there was no effect of baking time towards the
consumer acceptance of rice bran brownies in terms of taste
As shown in 2igure 3.4, there was no significant different of the rice
bran brownies made using different baking time towards the consumer acceptance
in term of taste parameter. There was no interaction between rice bran
concentrations and baking time towards the consumer acceptance of rice bran
brownies in term of taste parameter.
4.#.1.$ Te%ture
7ice +ran 6oncentration
3#>
Texture was chosen as one of the parameter in the hedonic test to observe the
consumer preference towards the different concentration of rice bran and different
baking time incorporated during the making of rice bran brownies.
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&
The range of hedonic scaling 8 (;extremely dislike, ";dislike,
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The result of the effect of rice bran concentration toward the consumer
acceptance of texture could be seen in 2igure 3.((. 2rom the statistical analysis
using two factor A/01A, there was effect of rice bran concentration towards the
consumer acceptance of rice bran brownies in terms of texture.
As shown in 2igure 3.((, there was significant different of the rice
bran brownies made using different concentration of rice bran towards the
consumer acceptance in term of texture parameter. The highest acceptance was
given by rice bran brownies made with #> rice bran concentration and the lowest
acceptance was given by rice bran brownies made with 3#> rice bran
concentration. 2rom 2igure 3.4, it also could be seen that there was no significant
different between rice bran brownies made using (#, "# and rice bran
concentration. This result was coherent with the research conducted by Buang et
al !"##&%, in that research the increased rice bran concentration lowered the
consumer acceptance of the pork meatball products in term of texture parameter.
This result was also supported by another research conducted by 9elahaye et al
!"##&% which was the study of rice bran utilization in frozen pizza. ensory
analysis was conducted to determine the consumer acceptance of frozen pizza,
and textural acceptance was one of the parameter observed in the sensory analysis,
which specifically was hardness. The research resulted with lowered sensory
acceptance toward the hardness parameter as the rice bran concentration
increased.
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+aking Time3."&
3.<
3.
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gelatinization, and moisture loss. These occurrences could possibly affect the
texture of the final product which could affect the consumer preference toward the
texture of the rice bran brownies.
Table 3." *nteraction of 7ice +ran 6oncentration and +aking Time towards Texture -arameter
+aking Time7ice +ran 6oncentration
#> (#> "#> 3#>
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two factor A/01A, there was effect of rice bran concentration towards the
consumer acceptance of rice bran brownies in terms of overall parameter.
7ice +ran 6oncentration
#
(
"
<
3
&
$
&.($
3.43.&$ 3.&&
3#>
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&The range of hedonic scaling 8 (;extremely dislike, ";dislike, rice bran
concentration. 2rom 2igure 3.(
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+aking Time3.34
3.&
3.&"
3.&3
3.&$
3.&4
3.$
3.$"
3.$3
3.$$
3.$
3.$&
3.&3
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Table 3.< *nteraction of 7ice +ran 6oncentration and +aking Time towards Texture -arameter
+aking Time7ice +ran 6oncentration
#> (#> "#> 3#>
rice bran and 3& minutes baking time were not significantly
different as can be seen in the Table 3.
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4.#.# P"si!al Analsis
4.#.#.1 Te%ture
7ice +ran 6oncentration
#
(###
"###
3#>
The texture of rice bran brownies made using different rice bran concentration and
different baking time analyzed using texture analyzer. The textural parameter
which was observed was hardness parameter. The result of the effect of rice bran
concentration toward the hardness parameter could be seen in 2igure 3.(&.
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&2igure 3.(& Dffect of 7ice +ran 6oncentration Towards Bardness -arameter
2rom the statistical analysis using two factor A/01A, there was
effect of rice bran concentration towards the hardness parameter of rice bran
brownies. As shown in 2igure 3.(&, there was significant different of the rice bran
brownies made using different concentration of rice bran towards the hardness
parameter. The highest value of hardness was given by rice bran brownies made
with 3#> rice bran concentration and the lowest one was given by rice bran
brownies made with #> rice bran concentration. 2rom 2igure 3.(&, *t could be
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seen that as the rice bran concentration increased the value of hardness also
increased. The hardness value of rice bran brownies made with 3#> rice bran
concentration was higher and significantly different compared to the rice bran
brownies made with # and (#> rice bran concentration, however it was not
significantly different with rice bran brownies made with "# and rice bran
concentration. This result is similar with several result which was already
conduced, regarding the incorporation of rice bran in the food products. Buang et
al !"##&% studied the effect of rice bran concentration towards the hardness of
pork meatballs, and it resulted in the increasing of hardness value as the rice bran
concentration increased. Another research was conducted by airam et al !"#((%,
and showed similar result, in that research the rice bran was incorporated in the
bread making, and as the rice bran concentration increased, the value of hardness
also increased. Therefore it could be assumed that the rice bran concentration had
positive correlation toward the increasing of the hardness value in a food product.
+aking Time
&4##
$###
$"##
$3##
$$##
$4##
)###
)"##
)3##
$
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2rom the statistical analysis using two factor A/01A, there was
effect of baking time towards the hardness parameter of rice bran brownies. As
shown in 2igure 3.($, there was significant different of the rice bran brownies
made using different baking time towards the hardness parameter. The highest
value of hardness was given by rice bran brownies made with && minutes baking
time and the lowest value was given by rice bran brownies made with
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stated by Bui et al !"##4%, water plays a major role during baking process because
water reacts with baking ingredients and evaporates when heated. The result of the
effect of rice bran concentration toward the hardness parameter could be seen in
2igure 3.(). 2rom the statistical analysis using two factor A/01A, there was
effect of rice bran concentration towards the moisture content of rice bran
brownies. *t could be seen in 2igure 3.() that there was significant different of the
rice bran brownies made using different concentration of rice bran towards its
moisture content.
7ice +ran 6oncentration
#
#.#"
#.#3
#.#$
#.#4
#.(
#.("
#.(3
#.($
#.(4
(".$>
(3.#(3.34>
(&.$)>
().#>
#>
(#>
"#>
3#>
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&2igure 3.() Dffect of 7ice +ran 6oncentration Towards oisture 6ontent
The highest moisture content was given by rice bran brownies made
with 3#> rice bran concentration and the lowest one was given by rice bran
brownies made with #> rice bran concentration. 2rom 2igure 3.(), *t could be
seen that as the rice bran concentration increased the moisture content also
increased. The moisture content of rice bran brownies made with 3#> rice bran
concentration was higher and significantly different compared to the rice bran
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brownies made with #, (#, "#, and rice bran concentration. The moisture
content of rice bran brownies made using rice bran concentration was not
significant different with the one made using "#> rice bran concentration,
however it was significant different with rice bran brownies made using # and
(#> rice bran concentration. This result was coherent with the result which was
conducted by aputra !"##4%, in that result rice bran was incorporated in cookies,
and by substituting wheat flour with "& > rice bran in the cookies the moisture
content of the product was increased. imilar result was obtained from research
conducted by 9elahaye !"##&%, whereas as the rice bran concentration increased
the moisture content of the product was also increased. 2rom this information, it
could be assumed that increasing the rice bran concentration might be contributed
in the increasing of moisture content in a bakery product.
+aking Time
#
#.#"
#.#3
#.#$
#.#4
#.(
#.("
#.(3
#.($
#.(4
#." (4.))>
(3.
((.3$>
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A/01A, there was effect of baking time towards the moisture content of rice bran
brownies. *t could be seen in 2igure 3.(4 that there was significant different of the
rice bran brownies made using different baking time towards its moisture content.
As shown in 2igure 3.(4, 7ice bran brownies made with
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different of the rice bran brownies made using different concentration of rice bran
towards its water activity. The highest water activity was given by rice bran
brownies made with 3#> rice bran concentration and the lowest one was given by
rice bran brownies made with (#> rice bran concentration. 2rom 2igure 3.(, *t
could be seen that as the rice bran concentration increased the water activity was
also increased.
7ice +ran 6oncentration
#.$$#
#.$)#
#.$4#
#.$#
#.)##
#.)(#
#.)"#
#.$4"#.$)4
#.$#
#.)#
#.)(<
#>
(#>
"#>
3#>
/otes 8 eans followed by the same letter are not significantly different in 9uncan Test at :;#.#&
2igure 3.( Dffect of 7ice +ran 6oncentration Towards 5ater Activity
Although the rice bran brownies made using (#> rice bran
concentration gave the lowest water activity among the others, from the statistical
analysis it was not significantly different with the rice bran brownies made using
(# and "#> rice bran concentration, however it was significant different with rice
bran brownies made using rice bran concentration. This result could
be correlated with the moisture content of the rice bran brownies, as the rice bran
concentration increased, the moisture content was increased, therefore it could be
assumed that the increasing moisture content affect the water activity in rice bran
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brownies, as stated in the theory above regarding the relation of moisture content
and water activity.
The result of the effect of baking time toward the water activity could
be seen in 2igure 3."#. 2rom the statistical analysis using two factor A/01A,
there was effect of baking time towards the water activity of rice bran brownies.
+aking Time
#.$
#.$$#
#.$)#
#.$4#
#.$#
#.)##
#.)(#
#.)"##.)(3
#.$"
#.$))
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increased the water activity was decreased. This phenomenon could be correlated
with the result of the moisture content analysis, whereas it showed similar result.
As the baking time increased, the moisture content decreased. ince water activity
had a relationship with moisture content, it could be inferred that the decreasing of
water activity as the baking time increased was affected by the moisture content of
the food product. 2rom the statistical analysis using two factor A/01A, there was
no interaction between rice bran concentrations and baking time towards the water
activity of rice bran brownies.
4.$ Pro%imate Analsis of Ri!e +ran -lour
The proximate analysis of rice bran flour was conducted to determine
the nutritional value of rice bran. The result of the proximate analysis could be
seen in the Table 3.3.
Table 3.3 -roximate 6omposition of 7ice +ran 2lour
Analysis Amount !7esearch 9ata% Amount !Buang et al, "##&%
oisture 6ontent &.&> ((."
Ash 6ontent (4.$> 4."#>
-rotein 6ontent ().(4> (&.##>
2at 6ontent (&.&(> "#.)>
6arbohydrate 6ontent 3
Total 9ietary 2iber 6ontent "".$)> "$.4>
2rom Table 3.3, it could be seen that rice bran flour which was used in
this research had different amount of proximate composition. This difference
could be attributed to the variety of the rice from which the rice bran was derived.
Buang et al !"##&% studied the composition of rice bran flour obtained from
different rice cultivator, and rice bran which derived from different rice varieties
would have different proximate composition. The total dietary fiber in rice bran
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flour used in this research was "".$)> as shown in Table 3.3, and according to
9elahaye et al !"##&% rice bran was considered as a good source of dietary fiber.
4.4 Determination of t"e +est ,luten -ree Ri!e +ran +ro0nies -ormulation
The best gluten free rice bran brownies formulation was determined
by sensory analysis. 2rom the result of sensory analysis, the gluten free rice bran
brownies which was selected as the best gluten free rice bran brownies
formulation was the rice bran brownies made using rice bran concentration
and && minutes baking time. 7egarding the statistical analysis, the rice bran
brownies made using concentration and && minutes baking time was not
significantly different with rice bran brownies made with (#> rice bran and rice bran and 3& minutes baking time, and (#> rice
bran and && minutes baking time as could be seen in Table 3. rice bran
concentration with
Ash 6ontent ".$4>
-rotein 6ontent $.)3>
2at 6ontent
6arbohydrate 6ontent 34.$(>
Total 9ietary 2iber ).)>
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According to Bandori !"##$%, the serving size of brownies is ("&
gram. +ecause the total dietary fiber content was ).)>, so the total dietary fiber
in the rice bran brownies per serving size was .)3 grams. As stated by 6hoo and
9reher !"##(%, food containing "#> or more 79A of dietary fiber could be
categorized as @high in or @rich in fiber, Therefore the best gluten free rice bran
brownies formulation obtained from this research could be categorized as food
which was high in fiber.