tarrah declemente f&n 453 individual project thursday afternoon lab · · 2006-05-10f&n...

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Tarrah DeClemente F&N 453 Individual Project Thursday Afternoon Lab Title: The Effect of Different Amounts of Gum Acacia (SuperWhite T) on Viscosity and

Mouthfeel of Diet Flavored Water

Abstract

The problem with many diet beverages is the lack of body and mouthfeel, and the bitter aftertaste

some have due to the sugar-replacer. By adding gum to these beverages the sensory appeal of

the product increases all the way from how the beverage looks to the taste of the beverage. By

making several solutions with varying amounts of gum and through objective and subjective

testing, the overall best product is determined; thus finding the correct amount of gum to add to a

solution to increase sensory appeal. Each solution undergoes a timed test through a burette and

is subjected to a sensory appeal card ranking each product on the Hedonic scale, ratings of

mouthfeel, thickness, and overall preference. The time it takes to run through the burette

increases with the increasing amount of gum. The sample with the most gum added is the least

liked throughout the experiment. Overall participants pick the control as the product preferred to

the solutions containing gum. The gum solution most preferred is that with the least amount of

gum added.

Introduction

The problem with many diet beverages is the lack of mouthfeel and the bitter aftertaste. By

adding a gum the beverage will become more viscous and the overall mouthfeel will be

improved. The gum used for this experiment was a new product called SuperWhite T, a type of

gum acacia that completely dissolves without tainting the flavor of the product. This gum was

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specifically developed to add mouthfeel and viscosity to diet beverages by enhancing flavor and

masking bitter tastes attributed to sugar replacers. (Berry 2005) SuperWhite T is also a source of

fiber; water-soluble fibers have been shown to decrease blood lipid levels which play an

important role in current rates of heart disease.(Gates 1993) If this product can not only add

sensory appeal to a beverage but also health benefits that makes a product even more practical.

Gums are used in product development for many reasons. Gums are used as binding agents,

emulsifiers, for flavor fixation, and foam stabilizers, just to name a few. The main aspects of

gum explored in this experiment were those of viscosity and mouthfeel. Beverage viscosity is an

important part of product quality. Humans can detect the slightest difference in the viscosity of

beverages; food product developers find that viscous beverages are more satisfying and delicious

than beverages without gum. The primary goal behind adding viscosity to beverages is to appeal

more to the senses. Viscosity adds body to the beverage which improves the look and the

sensation of substance in the mouth upon swallowing. Gums enhance and release flavor in

beverages; this is because flavor components avoid the hydrophilic phase of the beverage and

seek out association with colloidal molecules. (Klahorst 2002) The stability of the product is

important for maintaining appearance in beverages with fiber, flavor, pulp and protein

suspensions. Viscosity is a primary factor in beverage stability and prevention of settling and

aggregation of solids suspended in drinks. A common use of gum is as a stabilizer for citrus-

based carbonated and noncarbonated soft drinks. Flavors in beverages are quickly oxidized

when exposed to air, especially lemon flavoring. By coating a flavor capsule with gum the

product will maintain the flavor longer because the gum will dissolve and the lemon flavor will

remain in the solution.

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To find the effects of gum on diet beverages SuperWhite T will be added to flavored water

solutions and be tested both objectively and subjectively. (Berry 2005) Each beverage will

contain the same amount of water, Splenda®, and lemon juice, the only varying part of the recipe

will be the amount of gum added. 50 mL of each solution will be run through a burette and

timed to gauge the viscosity of each beverage. Each beverage will also be subjectively tested

through the Hedonic scale and comparison testing of mouthfeel, thickness, and preference of

each beverage.

The independent variable is the amount of gum added; the dependent variables are mouthfeel and

viscosity. The objective of this experiment is to find the percent gum solution which provides

the most sensory quality product. The solutions containing gum acacia will provide a better

mouthfeel in comparison to the reference sample Nestle lemon water.

Methods

The overall design of the experiment includes making three lemon water solutions and varying

only the amount of gum in each. Each solution contains 500mL of filtered water, 4 grams of

Splenda®, and 11.8 grams of lemon juice. The amount of gum added will be 4.05 g in sample

one, 8.10 g in sample two, and 12.15 g in sample three. The solutions will be mixed and then

objectively tested using a burette. 50 mL of each solution will be run through the burette and

timed to see how long it takes for the entire solution to run through. The burette test is a “simple

and inexpensive technique for measurement of kinematic viscosity of liquids, based on the

discharge time of liquid through a standard glass burette.” (Igathinathane 2005) A sensory

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scorecard will subjectively test each sample based on: Hedonic scale rating, mouthfeel,

thickness, and overall likeability.

Procedure

1. Obtain the reference sample (Nestle lemon water).

2. Using a Brita filter, filter 1500mL of tap water.

3. Using fresh lemons, cut the lemon into wedges and then squeeze the juice into a metal screen

sifter. This will prevent pulp from getting into the beverage. Filter as many times as necessary.

4. Prepare three sample solutions with the following recipe:

500 mL of filtered water

4 g Splenda® sweetener

11.8 g lemon wedges juice

5. Mix the water, Splenda®, and lemon juice together until all Splenda® is dissolved.

6. Once the basic solutions are made add the following amounts of SuperWhite T acacia gum

accordingly:

Sample 1: 4.05g

Sample 2: 8.10 g

Sample 3: 12.15 g

7. Mix samples first by hand, use a handheld mixer if all the gum will not dissolve. Sometimes

just letting the solutions sit for a few minutes allows the gum to absorb and dissolve on its own.

8. Once completely mixed, label samples with 3 digit sample code:

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Sample Description

Amount of

Gum (g)

888 Control 0.00

642 1/2 Tbsp 4.05

712 1 Tbsp 8.10

596 1.5 Tbsp 12.15

9. Take a 50 mL sample of each solution and using a burette time how long it takes for each

solution to run through. Record this information.

10. Pour samples of each solution into small plastic soufflé cups.

11. Using a sensory score card conduct sensory tests to find the product with the most taste

appeal.

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Sensory scorecard used for subjective testing:

Please mark the line next to the statement you agree with.

Which of the following samples do you like better? 888 or 596 642 or 712 Which sample has the best mouthfeel? ___ 642 ___ 888 ___ 712 ___ 596 Which sample tastes thicker? ___ 888 ___ 642 Which sample tastes thicker? ___ 642 ___ 596 Overall (considering taste and mouthfeel) which sample do you prefer? ___ 642 ___ 888 ___ 712 ___ 596

642 888 712 596 __Like extremely __Like very much __Like moderately __Like slightly __Neither like nor dislike __Dislike slightly __Dislike moderately __Dislike very much __Dislike extremely

__Like extremely __Like very much __Like moderately __Like slightly __Neither like nor dislike __Dislike slightly __Dislike moderately __Dislike very much __Dislike extremely

__Like extremely __Like very much __Like moderately __Like slightly __Neither like nor dislike __Dislike slightly __Dislike moderately __Dislike very much __Dislike extremely

__Like extremely __Like very much __Like moderately __Like slightly __Neither like nor dislike__Dislike slightly __Dislike moderately __Dislike very much __Dislike extremely

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This experiment should be conducted three times using the exact same methods. When

conducting the subjective methods the samples should be lined up randomly and the control

should not be put either first or last. The order should be as follows: 642, 888, 712, and 596.

Sensory evaluators should take a sip of each solution and keep the sample in their mouth long

enough to evaluate the texture of the beverage. Evaluators may drink as much or as little of the

beverage sample as they would like.

Results Trial 1

Table 1: Seconds taken to run through burette Sample Time (sec)

888 72 642 72 712 75 596 80

Time Taken to Run Through Burette

68

70

72

74

76

78

80

82

Control Sample 1 Sample 2 Sample 3

Sample

Tim

e (s

econ

ds

Figure 1

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Table 2: Hedonic Scale Rating Responses

Hedonic Rating 642 888 712 596 Like extremely Like very much 2 4 2 1 Like moderately 4 4 2 1

Like slightly 2 1 3 2 Neither like nor

dislike 1 Dislike slightly 1 1 3 3

Dislike moderately 1 1 1 2 Dislike very much 2 Dislike extremely

Table 3: Sample Preferred in Comparison Tests Sample Preferred

642 4 888 9 712 1 596 1

Sample Preferred in Comparison Tests

0

1

2

3

4

5

6

7

8

9

10


Sample

Num

ber

of p

eopl

e th

at c

hose

sam

ple

Figure 2

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Table 4: Number of Ratings for Best Mouthfeel Sample Best Mouthfeel

642 4 888 4 712 3 596

Amount of Ratings for Best Mouthfeel

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5


Sample

Num

ber

of p

eopl

e th

at c

hose

sam

ple

Figure 3

Table 5: Number of ratings for Thicker Sample in Comparison Test

Sample Rated thicker

888 8

642 3

10

Amount of Ratings for Thickest (Comparison Test)

0

1

2

3

4

5

6

7

8

9

Control Sample 1

Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 4


Sample Rated thicker 642 3 596 8


0

1

2

3

4

5

6

7

8

9

Sample 1 Sample 3

Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 5

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Table 7: Number of Ratings for Overall Preference

Sample Overall

preference 642 2 888 5 712 3 596 1

Overall Preference of Samples

0

1

2

3

4

5

6


Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 6

Trial 2

Table 8: Seconds taken to run through burette Sample Time (sec)

888 71 642 75 712 78 596 80

12

Time Taken to Run Through Burette

66

68

70

72

74

76

78

80

82


Sample

Tim

e (s

econ

ds

Figure 7

Table 9: Hedonic Scale Rating Responses

Hedonic Rating 642 888 712 596 Like extremely 1 Like very much 1 2 1 Like moderately 4 2 3

Like slightly 4 1 Neither like nor

dislike 1 1 2 3 Dislike slightly 3 3 2

Dislike moderately 3 Dislike very much 1 1 Dislike extremely 1

Table 10: Sample Preferred in Comparison Tests Sample Preferred

642 5 888 8 712 5 596 2

13

Sample Preferred in Comparison Test

0

1

2

3

4

5

6

7

8

9


Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 8

Table 11: Number of Ratings for Best Mouthfeel Sample Best Mouthfeel

642 2 888 5 712 2 596 1

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Amount of Ratings for Best Mouthfeel

0

1

2

3

4

5

6


Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 9


Sample Rated thickest

888 7

642 3


0

1

2

3

4

5

6

7

8

Control Sample 1

Sample

Num

ber o

f peo

ple

that

cho

se s

ampl

e

Figure 10

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Sample Rated thickest

642 1

596 9

Amount of Ratings for Thickest

0

1

2

3

4

5

6

7

8

9

10

Sample 1 Sample 3

Sample

Num

ber

of p

eopl

e th

at c

hose

sam

ple

Figure 11

Table 14: Number of Rankings for Overall Preference Sample Overall preference

642 3 888 6 712 1 596

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Overall Preference of Samples

0

1

2

3

4

5

6

7


Sample

Num

ber

of p

eopl

e th

at c

hose

sam

ple

Figure 12

Discussion This experiment evaluated the sensory effects of gum acacia. Only two trials were conducted

because the original amounts of gum in the recipe were far too high and the solutions tasted

terrible. So the first trial was spent figuring out which variable amounts of gum to use. Trials 2

and 3 will be referred to as trials 1 and 2, were replicated and used objective and subjective

methods to obtain the results of this experiment.

The objective method used was the burette timing test. 50mL of each solution were ran through

the burette and timed. The results for the burette test from trial 1 can be found in table 1. As

seen in table 1 samples 888 and 642 took 72 seconds to empty out of the burette. Sample 712

took 75 seconds and sample 596 took 80 seconds. For trial 2 the results can be found in table 8.

Sample 888 took 71 seconds, sample 642 took 75 seconds, sample 712 took 78 seconds, and

sample 596 took 80 seconds to run through the burette. Figures 1 and 7 compare the results

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graphically, again showing how long each sample took to run through the burette. The control

sample (888) took the least amount of time to run through, the solution made with the least

amount of gum took the same amount of time as the control in trial one, but four seconds longer

in trial 2. The solution with the second highest amount of gum took longer than both solutions

with less gum added, and the sample with the most amount of gum (596) took the longest to run

through the burette in both trials. These results comply with the idea that the more gum added

the more viscous the solution will become. A thicker solution will take a longer time to run

through the burette. This "time-dependent thickening flow behavior" was demonstrated in a

study done on the structure of acacia gums and the effect on fluid activity. (Lefebvre 2002)

The subjective tests were a little more involved and asked participants to rank the beverage

solutions on the Hedonic scale, choose which solution they preferred in a comparison test,

compare thicknesses of beverages, and choose an overall preferred solution. The first sensory

evaluation was the hedonic scale which had participants rank solutions on a likeability scale.

Trial 1 results can be seen in table 2. For sample 642 the results were: two participants liked the

solution very much, four liked the solution moderately, two liked the solution slightly, one

neither liked nor disliked the solution, one disliked the solution slightly, and one disliked the

solution moderately. For sample 888 the results were: four participants liked the solution very

much, four liked the solution moderately, one liked the solution slightly, one disliked the

solution slightly, and one disliked the solution moderately. For sample 712 the results were: two

participants liked the solution very much, two liked the solution moderately, three liked the

solution slightly, three disliked the solution slightly, and one disliked the solution moderately.

For sample 596 the results were: one participant liked the solution very much, one liked the

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solution moderately, two liked the solution slightly, three disliked the solution slightly, two

disliked the solution moderately, and two disliked the solution very much.

Trial 2 results can be found in table 9. For sample 642 the results were: one participant liked the

solution very much, four liked the solution moderately, four liked the solution slightly, and one

neither liked nor disliked the solution. For sample 888 the results were: one participant liked the

solution extremely, two liked the solution very much, two liked the solution moderately, one

neither liked nor disliked the solution, three disliked the solution slightly, and one disliked the

solution extremely. For sample 712 the results were: three liked the solution moderately, one

liked the solution slightly, two neither liked nor disliked the solution, three disliked the solution

slightly, and one disliked the solution very much. For sample 596 the results were: one liked the

solution very much, three neither liked nor disliked the solution, two disliked the solution

moderately, three disliked the solution slightly, and one disliked the very much.

Overall these results show that participants favored the control (888) and the solution with the

least amount of gum (642). The solution that was the most highly disliked was solution 596,

which contained the highest amount of gum. Participants stated that the solution had a strange

taste similar to a chalky, dusty taste. Sample 712 was equally ranked on both the like and dislike

portion of the scale with two participants in the middle, having no preference. Many of the

participants stated that they liked 888 the best because it tasted like Propel lemon water, a

Gatorade product; whereas some participants stated they disliked the control due to the funny

aftertaste, which can be attributed to the sugar replacer.

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The next subjective tests were comparison tests for likeability. Samples 888 and 596 were put

together, and samples 642 and 712 were put together. This was designed to see which sample

participants preferred between the two middle solutions. Table 4 shows the results from trial 1:

sample 642 was picked four times over 712 which was chosen once. Nine participants chose

sample 888 over 596 which was chosen once. Some participants were confused by the way the

question was setup on the survey. All four samples were listed beneath the question asking

participants to choose which sample they liked better; some participants only circled one of the

four. For trial 2 the results can be seen in table 10. The results between 888 and 596 showed

again an overwhelming preference to the control with eight participants choosing 888 and two

choosing 596. The results were split between 642 and 712 with five participants choosing each

respectively. Figures 2 and 8 show the results of these trials graphically and it is easy to judge

which solutions were preferred.

The next question asked which sample provided the best mouthfeel. Texture and mouthfeel are

fundamental sensory properties of foods and beverages. (Guinard 1996) All solutions were

evaluated at once. The trial 1 results can be seen in table 4 and figure 3. Sample 642 was chosen

as having the best mouthfeel by four participants, sample 888 was also chosen by four

participants, and sample 712 was chosen by three participants. Sample 642 had the least amount

of gum added and therefore the closest in composition to the control, so it is not surprising that

this sample was the picked the most. For this test it is possible that participants still were swayed

by the taste of each sample. Table 11 and figure 9 show the results from trial 2. Sample 642 was

picked by two participants, sample 888 was chosen by five participants, table 712 was chosen by

two participants, and one participant chose sample 596. Again the control was the most popular

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choice but in actuality, had the least mouthfeel because there was no gum in this product. This

may also be an indication that participants are choosing based on the taste of the product.

Next participants were asked to choose which sample tasted thicker in two comparison tests,

testing samples 888 and 642, and then 642 and 596. Trial one results are in tables 5 and 6 and

figures 4 and 5. For the first comparison eight participants chose sample 888 as being thicker

than 642, which was chosen by three participants. The second comparison results were that eight

participants chose 596 as being thicker than 642 which was chosen by three participants. These

results go along with what is true, 596 has the most amount of added gum and is the thicker

solution over 642. The control (888) and sample 642 are very similar in content, but 642 is

thicker. Trial 2 results can be found in table 12 and 13 and figures 10 and 11. Seven participants

chose sample 888 as being thicker than 642 which was chosen by three participants. The second

comparison test results were nine participants choosing 596 as thicker than 642 which was

chosen by one participant. Again this goes with what is true, 596 contains the most gum and is

the thickest of all the solutions.

Participants were finally asked to choose which sample they preferred overall. Trial 1 results can

be found in table 7 and figure 9. Overall the most participants preferred the control with five

participants, 712 was ranked next with three participants, 642 next with two, and 596 last with

one participant preferring it most to the other samples. Trial 2 results can be found in table 14

and figure 12. Overall six participants chose the control sample (888), next was 642 with three

participants, and next was 712 with one participant. So based on both trials the control sample

was preferred to any of the samples containing gum. The solution with the least amount of gum

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was liked best overall with five participants ranking it for the overall preference, 712 had four

participants’ preferences, and 596 was liked the least with only one participant liking it the most.

The hypothesis for this experiment was that the products containing gum would provide a better

mouthfeel in comparison to the reference sample Nestle lemon water. Participants chose the

control substance as having the best mouthfeel, and as the overall preferred sample, so this

hypothesis was not proven to be correct.

If this experiment could be done again, the control sample would be made the same way as the

other samples with no gum added. By having a control sample that is a product on the market it

was difficult to compare homemade samples to the overall quality of the machine made product.

Many participants commented positively on the taste of the control (888) because it reminded

them of a product they had already consumed. Another factor that adds to the results varying or

not being quite right is the fact that the sensory evaluators were not consistent between both trials

and were untrained students. As stated in a Food Product Design article talking about the

importance of sensory panels and how to properly compose a panel: “To make the results of

sensory testing most useful, they have to be consistent. To achieve consistency, the sensory panel

must be carefully selected or the information may be skewed.” (Hegenbart 1992) The flavor of

water is mainly determined by its mouthfeel and this should be the main concern when

comparing water. (Mischa 2005) From all of the tests performed evaluating sensory appeal it is

clear that the participants in this experiment did not take to the solutions containing gum.

Perhaps if doing this experiment over by adding food coloring participants would not think of the

solution as water, and would not then have that comparison in their mind. If the solutions were

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colored participants would think more of juices or other noncarbonated beverages and in this

sense may become more aware of mouthfeel instead of thinking of the mouthfeel of water. Also

the question that participants were confused by on the survey should be broken up into two

questions, so that one of each comparison is chosen.

References Berry, Donna. 2005. Through Thick and Thin. Food Product Design. Vol. 15 Issue 2, 35-55. Chambrun, J. and Millery, J. 2001. Liquid compositions, especially beverages, comprising at least two distinct phases forming a motif, and their manufacture. Patent application. Dunnewind, B., Janssen, A., Vliet, T., Weenen, H. 2004. Relative importance of cohesion and adhesion for sensory stickiness of semisolid foods. Journal of Texture Studies. Vol. 35, Issue 6, 603-620. Gates, J.E., A.F. Miller, C.D. Jensen, and J.H. Whittam. 1993. The effect of acacia gum and water-soluble dietary fiber mixture on blood lipids in humans. Journal of the American College of Nutrition. Vol. 12, Issue 2, 147-54.

Guinard, J. and Mazzucchelli, R. 1996. The sensory perception of texture and mouthfeel. Trends in Food Science and Technology. Volume 7 Issue 7, 213-219.

Hegenbart, S. 1992. An Inventory of the Toolbox. Food Product Design. http://www.foodproductdesign.com/archive/1992/0592CS.html

Igathinathane, C., Malleswar, V., Rao, A., Pordesimo, L., Womac, A. 2005. Viscosity Measurement Technique Using Standard Glass Burette for Newtonian Liquids. Instrumentation Science & Technology. Volume 33, 101-125.

Klahorst, S. 2002. Beverage Viscosity, Any Way You Like It! Food Product Design. http://www.foodproductdesign.com/archive/2002/0102AP.html. Lefebvre, Jaques, Denis Renard, Paul Robert, Christian Sanchez, Christophe Schmitt. 2002. Structure and rheological properties of acacia gum dispersions. Food Hydrocolloids. Vol. 16 Issue 3, 257-67. Mascha, M. 2005. Mouthfeel – a Strange but Important Word for Water Connoisseurs. Fine Waters.

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