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The Effect of Inulin as a Fat Replacer in a Regular Homemade Chocolate Pudding

Individual Project: Written Report Olga Suchshinskaya & Maggie McKay Lab Section 003 November 24, 2008

I. Title: The Effect of Inulin as a Fat Replacer in a Regular Homemade Chocolate Pudding.

II. Abstract: Inulin is a functional ingredient usually extracted from the chicory root that has become

increasingly popular in the food industry due to its potential health benefits as well as its

functional properties in foods. Both an indigestible fiber and a prebiotic food, it is most known

for promoting digestive health. When added to food products, it is mainly used to replace fat

because it has been shown to simulate the creamy texture that fat contributes to food products.

The type of inulin used in this experiment was HP inulin, which is especially designed for

replacing fat. It has a high degree of polymerization, and is therefore only slightly soluble in

water. It forms a gel when mixed in aqueous solution, works well with other gelling agents,

retains water, and stabilizes gels. It also has been show to contribute little viscosity to a product.

In this experiment, the effects of different inulin concentrations on a cornstarch-based

homemade chocolate pudding were compared to the effects of butter in the original recipe. The

control was the original recipe that used 5.57 g butter per 100g pudding. The three variables

were 10g inulin/100g pudding, 20g inulin/100g pudding, and 30 g inulin/100g pudding. Results

revealed no significant difference (p > 0.05) in viscosity between the control and the 10 g and 20

g inulin samples. However, there was a significant increase (p < 0.05) in viscosity between the

aforementioned samples and the 30 g inulin sample. There was no significant difference (p >

0.05) between the activities of water of the four samples. For each of the three trials, 6-7

volunteers completed a subjective sensory panel to evaluate the color, sweetness, texture, and

palatability of the four variables. Overall, the 30g inulin was ranked as having the most preferred

color. On the other hand, the control was ranked as having the best sweetness, texture, and

palatability. The 10 g inulin sample was ranked as having the second-best sweetness, texture,

and palatability. Based on these results, using 10 g of inulin or less per 100 g of chocolate

pudding seems to best simulate the properties of the full-fat version of the pudding while also

providing similar texture, sweetness, and palatability. In addition, adding inulin allows for the

aforementioned health benefits.

III. Introduction:

A) Background Information: The Effects of HP Inulin, Butter, Cornstarch, and Milk Proteins on Homemade Chocolate Pudding

Inulin is a functional ingredient that has become increasingly popular in the food industry. It

is a natural fructan used by plants for carbohydrate storage (Niness 1999). Plants containing inulin

include wheat, onion, bananas, garlic, and chicory (Niness 1999). Typically, food industries extract

the fructan from the chicory root (Niness 1999).

Inulin is proving to be a successful functional ingredient in foods due to its research-

supported health benefits as well as favorable effects on the properties of some food products.

According to an article by Kathy Niness published in the Journal of Nutrition, inulin is used as a fat

and/or sugar replacement in foods, thus helping to reduce the total kcal of a product (Niness 1999).

Not only that, but as it is an indigestible fiber, it enhances one’s daily fiber intake, and can thus help

people meet the American Heart Association recommendations of 14 g fiber per 1000 kcal (AHA

2008). An increase in one’s intake of inulin would improve digestive health, promoting the

regulation of bowel movements (Roberfroid 2005). Similarly, inulin is a prebiotic food, meaning that

it promotes the growth of beneficial micro flora in the colon. More specifically, it is fermented by

bifidobacteria. As a result, inulin helps to increase the proportion of beneficial bacteria in the colon,

and decrease the proportion of potentially harmful bacteria (Roberfroid 2005).

Stemming from its role as an indigestible fiber, inulin has also been shown to decrease

serum triglyceride and blood cholesterol levels in patients with hypertriglyceridemia or

hypercholesterolemia (Niness 1999 and Roberfroid 2005). Hence, inulin may help reduce one’s risk

for cardiovascular disease. Moreover, as research shows it does not have great influence on serum

glucose levels, it can be safely used by diabetics (Niness 1999).

Finally, inulin may also improve calcium storage in bones. According to Niness, over ten

research studies have shown that inulin enhances calcium absorption and deposition in the bones of

rats and humans (Niness 1999).

Questions that still remain unanswered regard the daily amount of inulin needed to achieve

the different health benefits inulin provides: bowel regulation, prebiotic effects, increased calcium

absorption, a decrease in serum cholesterol and triglyceride levels, etc. There seems to be much

debate on this issue of how much inulin will cause an increase in its different health benefits. Cargill

Health and Food Technologies claim that consuming 5 g of inulin a day will provide one with the

prebiotic effects of inulin, and that consuming 8 g a day will increase calcium absorption (Cargill

Inc. 2005). However, in a study published in Nutrition, the author Dahl stated that it is acceptable to

consume as much as 40 g of inulin per day. Furthermore, in Dahl’s study, which observed the effects

of inulin on patients in wheelchairs, the 12.6 g/day of inulin given to subjects throughout a three-

week period did not cause an increase in calcium absorption. Dahl further cited another study in

which subjects receiving 17 g/day of inulin had no increase in calcium absorption. On the other

hand, Dahl also stated other studies in which acute calcium absorption was noted in patients who

were suffering from a health condition that required greater calcium absorption (Dahl 2005). In terms

of bowel regulation, the 12.6g/day administered to subjects in Dahl’s study was enough to provide

bowel regularity (Dahl 2005). But is that the minimum amount needed to provide regularity? The

same question can be proposed in terms of inulin’s effects on serum cholesterol and triglyceride

levels: Just how much is enough? One thing that is certain, however, is inulin’s ability to lower the

total kcal and fat content of foods.

Besides its potential to provide health benefits, inulin also has a positive effect on the

properties of food products. In fact, it is used to replace fat and/or sugar in baked goods, table

spreads, fillings, dairy products, frozen desserts, and dressings (Niness 1999). As stated by Hunter in

Consumers’ Research Magazine, inulin lowers the caloric value of food while enhancing the texture

and thickness of the food, producing a creamy mouth-feel (Hunter 2003). Inulin is also known to

raise the viscosity of sauces, increase air and thus volume of nonfat icings and whipped toppings,

and add a sweet taste to the product—all the while not affecting the color of the food (Hunter 2003).

A study published in the International Dairy Journal by Tarrega confirmed some of these food-

enhancing effects of inulin. In this study, the researchers compared fat-free, starch-based dairy

desserts that contained different inulin concentrations, with a full-fat version of the dessert. The fat-

free samples containing inulin increased in sweetness, thickness, and creaminess as the inulin content

increased. Moreover, the inulin-containing samples that had a low starch concentration were rated as

having the same thickness as the full-fat version of the dessert (Tarrega 2006).

A study by El-Nagar produced similar results when comparing an inulin-containing low-fat

yogurt ice cream with a high fat version of the ice cream. El-Nagar explained that inulin is

hygroscopic, meaning that it binds tightly to water, forming a gel-like network and thus contributing

to the viscosity and thickness of a product (Nagar 2002). Since it binds water so tightly, it also is a

strong stabilizer of molecules, thus improving the consistency of the ice cream. As a result, the

inulin-containing sample was rated by participants as being similar in quality to the high-fat version,

and also as having a soft and smooth texture. In this experiment, increasing the inulin content from

10g to 14g to 18g did not have an increasing effect on texture (Nagar 2002). Thus, the effects of

inulin may reach a maximum value at a certain inulin concentration.

It is important to note that there are different types of manufactured inulin products. Though

all types of inulin share some general characteristics in terms of their effects on food properties, they

also affect food properties in unique ways due to differences in their structures. In this experiment,

Raftiline HP gel was the type of inulin used in all three trials. Standard inulin is made up of 92%

inulin and 8% sugars. HP inulin, on the other hand, does not contain sugars (Foodnavigator.com

2003). Unlike other types of inulin, HP inulin is known as “high performance” because it has a high

degree of polymerization. In fact, each of its molecules has a degree of polymerization of 10 or more

(Franck 2002). Due to the long length of its molecules, HP inulin is only slightly soluble in aqueous

solutions at room temperature; more specifically, HP inulin only has a water solubility of 25 g per

liter of water, while standard inulin has a water solubility of 120 g per liter of water (Franck 2002).

As HP inulin has low water solubility, it easily forms a gel network in aqueous liquid. Thus,

it works well with other gelling agents such as cornstarch in pudding. In particular, it works with

other gelling agents in a mixture to stabilize the gel and prevent syneresis by immobilizing water.

This contributes to the texture, mouth-feel and thickness of the end product (Franck 2002).

According to A. Franck, HP inulin’s ability to stabilize gels contributes to its successful use

as a fat replacement in products such as low-fat dairy products (Franck 2002). Butter—a fat often

used in dairy dessert products—is made of 80% fat (usually bovine fat), 18% water, and 2% milk

solids (Charlie and Weaver 1998). It is a water-in-oil emulsion, and thus helps a mixture to retain

water. This effect results in a product with a smooth mouth-feel and a creamy texture (Charlie and

Weaver 1998). As stated previously, inulin’s ability to immobilize water produces similar effects in

mouth-feel and texture (Franck 2002).

HP Inulin also serves as a viable fat replacer in foods because when added to foods in the

correct amount, it seems to simulate the qualities of fat without greatly altering other properties of

the food. For example, A. Franck notes that HP inulin contributes a low amount of viscosity when

added to water (Franck 2002). Thus, when used in the correct amount it can simulate the creamy

texture of fat without significantly altering the thickness of the original food product. In a like

manner, although it immobilizes water, Raftiline HP gel does not seem to significantly affect the

water activity of a food product. For example, in an experiment studying the effects of HP inulin on

soy protein gelation, Tseng reports that there was no significant difference in water activity between

the control protein gel and the gel with added inulin (Tseng 2008). In the same experiment, the HP

inulin decreased the pore sizes of the soy protein gel, thus producing a finer texture (Tseng 2008).

Therefore, it seems that inulin can serve as a fat replacement without significantly affecting other

desired properties of foods.

In this experiment, inulin was added to a cornstarch-based homemade chocolate pudding/pie

filling. Cornstarch is the main ingredient that causes the pudding to gel (Hegadorn 1971). In fact,

cornstarch has a high ability to thicken mixtures (Charlie and Weaver 1998). Like other starches,

cornstarch undergoes gelatinization and gelation to form a gel. Cornstarch granules are made mainly

of amylopectin and amylose. Upon being dispersed in water and exposed to heat (100 degrees C),

gelatinization begins to occur. Water (or other aqueous solution) enters the granules and causes them

to expand. Amylose then exits the granules and enters the surrounding solution, while the

amylopectin remains inside the granules. Some swollen granules then collapse and release water

(Daniel 2008). The process of stirring when making pudding assists in breaking the swollen starch

granules, thus facilitating gelatinization (Charlie and Weaver 1998). Upon cooling of the mixture,

gelation occurs. The long chains of amylose molecules in the solution bind together at certain points,

forming junction zones. These junction zones, which are stabilized by the cornstarch granules, trap

water in pockets. The result is the formation of a cornstarch gel (Daniel 2008), which contributes to

the thickness of the pudding.

Another ingredient in this chocolate pudding/pie filling recipe that contributes to the gelation

of the mixture is skim milk. Milk contains proteins such as casein and whey. When exposed to heat,

the whey protein denatures and coagulates. This protein coagulation—caused by the hydrophobic

regions of the protein attracting to one another upon denaturation—results in the formation of

junction zones, which trap water and forms a gel (Charlie and Weaver 1998 and Daniel 2008). Thus,

gel formation from milk protein also helps to stabilize the pudding and to increase viscosity or

thickness (Clausi 1957 and Daniel 2008).

B) Problem and Methods Used

The purpose of this experiment is to compare the effects of inulin versus butter on the

properties of a homemade chocolate pudding/pie filling. As many Americans are fighting the battle

between health and weight maintenance versus the temptation of fatty foods, why not create a low-

fat or fat-free dessert that may provide several health benefits (including lowering one’s cholesterol)

while also satisfying one’s craving for sweets? Creating a healthier chocolate filling that can be used

for either chocolate pie or pudding could provide consumers with yet another opportunity to make a

healthier food choice.

The independent variables in this experiment are the three different concentrations of inulin

added to 100g samples of pudding: 10 g, 20 g, and 30 g inulin per 100 g pudding. The dependent

variables include viscosity, water activity, and sensory traits such as color, texture, sweetness,

overall preference, and overall preference when eaten with a wafer cookie. Our control is the full-fat

version of the chocolate filling/pudding that is made with butter.

Several questions will be addressed by this experiment. First of all, will increasing the

amount of inulin in a chocolate filling increase the viscosity of the pudding? To measure viscosity,

the Brookfield Viscometer will be used. Another question is: Will inulin affect the water activity of

the filling? As mentioned previously, Tseng reports that inulin does not significantly affect the water

activity of a soy protein gel (Tseng 2008), but will the same effect occur in this filling? The Water

Activity System will be used to measure the activity of water of the samples. Finally, a comparison

of the texture, taste, color, etc. of a filling made with different inulin concentrations versus a full-fat

version of chocolate filling will be made. Do consumers prefer an inulin version of the filling versus

the full-fat version? Among the inulin samples, which concentration of inulin is most acceptable to

consumers? Do consumers find the inulin samples more palatable when eaten with a wafer cookie

(which simulates a chocolate pie crust)? To test these subjective qualities of HP inulin in chocolate

pie filling/pudding, we will use a subjective sensory panel. Hopefully, a product will be created that

has many health benefits and is also palatable to the consumer.

C) Hypothesis and Objectives:

In according with the null hypothesis, it is hypothesized that the inulin content of the pudding

will have no effect on thickness, water activity, texture and color compared to the full-fat chocolate

pudding made with butter.

The objectives of this experiment are to replace fat (in the form of butter) with inulin in order to

increase the fiber content, improve cholesterol levels, and promote growth of intestinal bacteria for

enhanced digestive health while maintaining the color, texture, taste, palatability, and food properties

(such as viscosity and activity of water) of the original chocolate pudding / pie filling.

IV. Methods:

A) Overall Design: The experiment was designed in order to test the effects of inulin as a fat replacement in a

regular homemade chocolate pudding/pie filling. The control was the full-fat version of the

pudding. The three variables were modified versions of the original recipe in which the fat (butter)

was replaced by 10 grams, 20 grams, or 30 grams of inulin per 100 grams of pudding.

To test the effects of inulin versus fat, two objective measures and one subjective measure

were used. Viscosity was measured using the Brookfield Viscometer, and water activity was

determined using the Water Activity System. Directions for using these instruments were found in

the Food Chemistry Laboratory (Weaver and Daniel 2003) on pages 107 and 131, respectively.

Sensory scorecards were utilized in order to obtain subjective measurements regarding taste, color,

texture, and palatability of the variables and control.

B) Procedure:

Recipe (Total: 449 g pudding)

100 g white sugar

15 g unsweetened cocoa powder

0.8 g cornstarch

0.9 g salt

400 ml skim milk (original recipe called for 650 ml of milk)

25 g margarine or butter (used in control)

100 g inulin

5 ml vanilla extract

(Note: Original recipe called for 650 ml of 2% milk, but recipe was altered and skim milk was used instead.

This was done to isolate the fat content so that butter would be the main fat source in the original recipe. Less

skim milk was used due to the low viscosity of skim milk versus 2% milk.)

Overall Approach: Prepared 2 batches of recipe simultaneously (449 g pudding made per batch),

measured out 200g of pudding for control and for each variable, added appropriate amounts of butter

or inulin, and blended all samples until they were as smooth in texture as possible.

1. Enough dry ingredients were measured out to make one batch of pudding and sifted

ingredients together with a sifter. The dry ingredients were placed into a cooking pot.

2. 400 ml of skim milk was measured and placed into a measuring cup.

3. 5 ml of vanilla extract was measured and placed into a small graduated cylinder.

4. Step 1 and Step 2 were repeated in order to make a second batch simultaneously.

5. Stove burners were turned to medium heat (Heat setting of 3 on stove burner).

6. The two pots with dry ingredients were placed on the burner.

7. 1/3rd of the skim milk was immediately added into each pot, and the mixtures were

stirred.

8. The rest of the skim milk was gradually added to each pot while stirring.

Mixture was brought to a boil.

9. Added vanilla extract to mixture and stirred.

10. Mixture was stirred for 20 minutes—the time necessary for pudding to thicken fully.

11. Stove burners were turned off.

12. While samples were warm, 4 samples of 200 g of pudding were measured using a

measuring cup, a dish, and a weight scale.

13. Each 200g sample was placed into a separate mixing bowl. Each bowl was labeled as

follows: Control, 10g inulin, 20g inulin, and 30g inulin.

14. The following variables were added to the appropriate 200 g sample:

Variable Sample

11.14 g butter Control (5.57 g butter/100g pudding)

20 g of inulin 10 g inulin/100g pudding

40 g inulin 20 g inulin/100g pudding

60 g inulin 30 g inulin/100g pudding

(Because 200 g samples were made instead of 100g samples, the amount of butter and

inulin added to each sample was doubled).

15. Butter was stirred into control with a rubber spatula.

16. Inulin samples were blended at blender speed of 2 until they were smooth in texture.

Blending utensils were washed before and after each individual sample was blended.

The following amount of time was needed to blend each sample:

Blending Time Sample

3 minutes 10 g inulin / 100 g pudding

4 minutes 20 g inulin / 100g pudding

5 minutes 30 g inulin / 100g pudding

17. Samples were placed into clear containers and brought to testing lab.

18. The Brookfield Viscometer was used to measure the viscosity of each sample. These

measures were taken at room temperature (20-25 degrees Celsius).

Each sample was placed in a clean 140 ml beaker. Enough of each sample was added to

fully cover tip of spindle. A spindle size of 7 was used for all samples. Viscosity

measures were taken at 6 rpm, 12 rpm and 30 rpm. Measures were recorded 30 seconds

after appropriate spindle speed was set and Brookfield Viscometer was turned on. All

percentages were between 10%-100%.

19. The Water Activity System was used to measure the activity of water for each sample. A

small amount of sample was placed inside the Water Activity System. Measures were

taken at room temperature (20-25 degrees Celsius).

20. Samples were given to participants of subjective sensory panel for evaluation.

Sampling and Randomization for Subjective Sensory Panel:

The subjective sensory panel was given to 6-7 students for each trial.

About 150 g of each sample was used for taste-testing. The samples were identified by

the following random numbers:

Sample 531 = control

Sample 294 = 10 g inulin



In Trial 1, about ¾ tablespoon of each of the four samples was placed in small, individual clear

plastic cups in the following order: Sample 897, Sample 294, Sample 531, and Sample 426. White spoons

were given for individual tasting. Wafer cookies were placed in a white Styrofoam bowl near the serving

tray, and participants were told to eat one when completing Question 5. Each participant therefore tried all

four samples. In this trial, the order of the samples was not switched between questions.

In Trials 2 and 3, 150 g of each sample was placed in an individual white Styrofoam bowl. The four

bowls were placed on a tray, along with a Styrofoam bowl filled with wafer cookies that were used for

answering Question 5. White spoons and plates were provided for each participant. Participants took their

own amount of pudding with their spoon (they only took one spoonful per sample). In Trial 2, the bowls

were set in the following order, from left to right: Sample 426, Sample 294, Sample 531, and Sample 897. In

Trial 3, the bowls were again set in the original order from left to right: Sample 897, Sample 294, Sample

531, and Sample 426.

21. Steps 1-20 were repeated two more times in order to complete three trials of the

experiment.

Subjective Sensory Panel Please rank the following chocolate pie filling samples according to the most appealing color (1) to least

appealing color (10).

Sample 897 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)

Sample 294 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)

Sample 531 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)

Sample 426 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)

Please taste each sample in front of you and then mark the line that best describes the texture

of the chocolate filling.

Sample 426.

_____________________________________________________________________ Extremely Moderately Slightly Slightly Moderately Extremely Creamy Creamy Creamy Gritty Gritty Gritty Sample 531 _____________________________________________________________________ Extremely Moderately Slightly Slightly Moderately Extremely Creamy Creamy Creamy Gritty Gritty Gritty

Sample 294 _____________________________________________________________________ Extremely Moderately Slightly Slightly Moderately Extremely Creamy Creamy Creamy Gritty Gritty Gritty Sample 897 _____________________________________________________________________ Extremely Moderately Slightly Slightly Moderately Extremely Creamy Creamy Creamy Gritty Gritty Gritty Please rank the chocolate filling samples in order of sweetness (1) being the one you thought was the most

sweet to (4) being the least sweet.

Sample 897 ________ Sample 294 ________ Sample 531 ________ Sample 426 ________

Please rank the chocolate filling samples in order of preference (1) being the one you liked most to (4) being

liked least.

Sample 897 ________ Sample 294 ________ Sample 531 ________ Sample 426 ________ Please rank the chocolate filling samples in order of preference (1) being the one you liked most to (4) being

liked least with the wafer cookie.

Sample 897 ________ Sample 294 ________ Sample 531 ________ Sample 426 ________

V. Discussion: A) Objective Measurements

Viscosity and water activity were the two objective measurements taken in order to compare the

effects of inulin versus fat (butter) on properties of the chocolate pudding. Figure 1 and Table 1 show the

average viscosities of the four samples (at room temperature) at 6 rpm, 12 rpm, and 30 rpm. Statistical

significance of the averages was calculated at 30 rpm. There was no significant difference (p > 0.05) in

viscosity between the control sample (27, 033.33 CP), the 10 g inulin sample (25, 633. 33 CP), and the 20 g

inulin sample (51, 200.00 CP). However, there was a significant increase in viscosity (p < 0.05) of the 30 g

inulin sample (111, 766.67 CP) compared to the aforementioned samples. These results are supported by A.

Franck, who stated that HP inulin contributes only a low amount of viscosity to an aqueous solution (Franck

2002). These results are also supported by Nagar, whose research study showed that there was no significant

effect on viscosity of low-fat yogurt ice cream as the inulin concentration was increased from 10 g to 14 g to

18g (Nagar 2002). Inulin’s little effect on viscosity seems to hold true up to a certain point. In other words,

inulin seems to have little effect on the viscosity of a product until a certain concentration of inulin per

amount of product is added. In this experiment, the amount of inulin added did not significantly affect

viscosity compared to the control until the inulin concentration reached 30 g per 100g of pudding. More

specifically, adding this much inulin caused the viscosity to significantly increase. Therefore, using

concentrations of inulin less than 30 g/ 100g pudding would produce a chocolate pudding with a viscosity

similar to that of the full-fat version.

Figure 1 also reveals that although there was no significant difference in viscosity between the

control, 10g inulin sample, and 20 g inulin sample, there was an overall trend for the viscosity to slightly

decrease as the amount of inulin increased from 0 g to 10 g. There may have been an error in the collection

of results, because no research was found to support the claim that inulin can lower the viscosity of a

product. On the other hand, there was an overall trend for the viscosity to increase as the amount of inulin

increased from 10 g to 20 g. Based on these results, adding no more than 10 grams of inulin may produce a

product that is most similar in thickness to the control; after all, the difference in viscosity between the

control and 10 g inulin samples was less than the difference in viscosity between the 10 g inulin and the 20 g

inulin samples.

Next, Figure 1 and Table 1 show that inulin does not alter the shear-thinning property of pudding.

Pudding is a pseudo plastic fluid, and thus decreases in viscosity as the shear rate increases (Daniel 2008).

Figure 1 shows that for each concentration of inulin, the viscosity (thickness) decreased as the rpm increased

from 6 to 12 to 30. This further supports that inulin can be used to replace fat in a regular chocolate pudding,

as it does not alter an inherent property of pudding.

Similar to results on viscosity, there was no significant difference (p > 0.05) in water activity

measurements between any of the four samples. Figure 2 displays these results. As Table 2 shows, the

average activity of water (measured at 22 degrees Celsius) of the four samples were as follows: Control =

0.890, 10 g inulin = 0.884, 20 g inulin = 0.883, 30 g inulin = 0.878. Tseng reported similar results in his

study on the effects of inulin on soy protein gels; in that experiment, there was also no significant difference

in water activity between the inulin samples and the control sample (Tseng 2008). Thus, although the inulin

gel binds water, it does not retain water to a greater extent than does the butter and the cornstarch gel

network. As a result, inulin at all three concentrations can be used to replace fat in chocolate pudding without

altering the activity of water and thus changing a property of the regular product.

B) Subjective Measurements

The results obtained from the sensory evaluation portion of the experiment were used to determine

the best amount of inulin that can be used without interference with the palatability of the product. The

experimenters used five sets of sensory criteria to test the product with butter and three varied amounts of

inulin in product, chocolate pudding. The first product served as the control and contained 5.57 g of butter

per 100 g of pudding but did not contain inulin. The second product contained 10 grams of inulin in 100 g of

pudding. The third product contained 20 grams of inulin in 100 grams of chocolate pudding and the last

product contained 30 grams of inulin in 100 grams of pudding. The five sets of sensory criteria used to rate

the product were color, texture, sweetness, overall product preference and overall product preference when

tasting a product with a cookie. Overall, the test subjects were able to differentiate between the different

samples and thus detect the increases of inulin in the chocolate pudding product.

In Table 3: Number of People per Specified Color Rank, it was observed that the color sensory

evaluation results indicated that the pudding product containing 30 grams of inulin was ranked as having the

most preferred color. This ranking may be due to the fact that the chocolate pudding products containing less

amounts of inulin appeared to be darker. This may have made consumers think that the darker-color

puddings had a dark chocolate flavor. The inclination for dark chocolate is an acquired taste and may not be

preferred by the majority of the population verses milk chocolate which usually has a sweeter taste. Thus, the

assumption is that the product containing 30 grams of inulin, which is lighter in color, resembles a milk

chocolate product and therefore may have been more appealing to the majority of test subjects than the

products with no inulin or products with less amounts of inulin. The pudding that was ranked as second most

appealing in color was the chocolate pudding containing 20 grams of inulin. The pudding ranked as the third

most appealing in color was the chocolate pudding containing 10 grams of inulin. The pudding ranked as the

least appealing in color was the product with no inulin. These results are different from those reported by

Hunter, who found that inulin does not affect the color of a product (Hunter 2003). However, the amounts of

inulin used by Hunter may not have been high enough in concentration to lighten the product.

In Table 4: Number of People per Specified Texture Rank, it was observed that the texture sensory

evaluation results indicated that the product with the best texture and the least grittiness was the pudding with

no inulin (the control). This sample contained 5.57 grams of butter in one hundred grams of chocolate

pudding instead of inulin. The pudding ranked as having the second-best texture was the chocolate pudding

containing 10 grams of inulin. The pudding ranked as third in texture was the product with 20 g of inulin.

The product ranked as having the grittiest texture was chocolate pudding containing 30 g of inulin. From this

one can conclude that as the amount of inulin increased, the chocolate pudding became grittier in texture to

the participants.

In Table 5: Number of People per Specified Sweetness Rank, it was observed that the sweetest taste

was exhibited by the product containing no inulin. The chocolate pudding with 10 g of inulin was ranked as

second in sweetness. The third-best product in terms of sweetness was noted to be the pudding containing 20

g of inulin and the least sweet product was the chocolate pudding with 30 g of inulin. This observation is

supported by Franck, who noted that HP inulin is not sweet due to the fact that the short-chain sugar

molecules have been removed (Franck 2002). This fact confirms that the control group-- in which regular

sugar was used—was ranked as being the sweetest product, and that the sweetness of the inulin samples

increased as less inulin was added. Moreover, the fact that HP inulin does not contribute sweetness to the

pudding indicates that it can work well as a fat replacer, since it can exhibit fat properties without modifying

the particular flavors of the product.

In Table 6: Number of People per Specified Preference Rank, it was noted that the most preferred

product was the chocolate pudding containing no inulin. The second best product preferred by the test

subjects was chocolate pudding with 10 g of inulin. The third best product ranked was the product with 20 g

of inulin and the least preferred product was the chocolate pudding containing 30 g of inulin. These results

correlate with the data mentioned above based on sweetness and texture of the product. The best texture and

most sweet products were ranked by test subjects in a similar manner in the preference ranking test.

In Table 7 a similar trend was observed by the test subjects when tasting the product with cookies as

in Table 6, Table 5 and Table 4. The most preferred product when tasted with a wafer cookie was the

chocolate pudding with no inulin added. The second most preferred product with a wafer cookie was the

chocolate pudding with 10 g of inulin. The third most preferred was the product with 20 g of inulin added.

The least preferred product with a wafer cookie was the chocolate pudding containing 30 g of inulin.

C) Overall Conclusion

Based on the results obtained from the sensory evaluation and the objective measures, one can

conclude that pudding containing 10 g of inulin is the best amount of HP inulin to use per 100 g of pudding

product. This is due to the fact that chocolate pudding containing 10 grams of inulin was ranked as the

second best choice on a consistent basis and also had a water activity and viscosity that was the most similar

to that of the control chocolate product. Thus, using 10 g of inulin in 100 g of chocolate pudding can serve as

an efficient fat replacer that creates a product that is similar to the control in thickness, taste, texture, and

palatability. In addition, unlike the full-fat pudding, pudding with 10 g of inulin can contribute health

benefits such as digestive health, increased calcium absorption, and cholesterol reduction.

D) Recommendations for Future Work

Recommendations and suggestions for future development of the product with HP inulin are to use

varied amounts of inulin up to 10 grams in one hundred grams of chocolate pudding, as well as trying to use

smaller amounts of inulin in a chocolate pie filling. The crust of the pie would help mask the grittiness of the

inulin. Another suggestion for future product development is using HP inulin in a sandwich cookie product.

HP inulin is moderately soluble and can be used as a fat replacement even up to 100% (Franck 2002). A

chocolate filling with inulin can be used in varied amounts with a vanilla cookie resulting in a chocolate

crème-filled sandwich cookie as the end product. This product may work well with HP inulin due to the fact

that the cookie crumbs may disguise the grittiness of the HP inulin. One concern with the development of

this product is the shelf stability of a sandwich cookie due to the fact that inulin has a relatively high water

activity which will induce growth of microorganisms, bacteria, or fungi.

VI. Results

Table 1: Average Viscosity versus Inulin Content Viscosity (rpm) Amount Inulin (g)

0 g 10 g 20 g 30 g 6 rpm 99333.33 94666.67 188433.33 475133.33 12 rpm 53333.33 53000 99766.67 236433.33 30 rpm 27033.33 25633.33 51200 111766.67

a aa

b

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

500000

0 5 10 15 20 25 30 35

Viscosity (C

P)

Amount Inulin (g)

Figure 1: Viscosity via Brookfield Viscometer

6 rpm

12 rpm

30 rpm

rpm 30: Bars not Bearing the Same Superscript are Statistically Significanlty Different, p<0.05

a

aa

a

0.8450.85

0.8550.86

0.8650.87

0.8750.88

0.8850.89

0.8950.9

0 10 20 30

Aw

Amount Inulin (g)

Figure 2: Aw According to Amount InulinBars bearing the same superscript are not significanlty different, p<0.05

Table 2: Average Water Activity verses Inulin Content (@22° C)

Amount Inulin (g) 0 g 10 g 20 g 30 g

Aw 0.89 0.884 0.883 0.878

Table 3: Number of People per Specified Color Rank Amount Inulin (g) 0 g 10 g 20 g 30 g

Color Rank # of People per Specific Color

Rank 1: Best Color 6 5 1 7 2 4 4 9 1 3 2 8 7 5 4: Worst Color 6 0 1 5

012345678910

0 10 20 30

# of Peo

ple pe

r Specific Co

lor

Rank

Amount Inulin (g)

1: best color

2

3

4: worst color

Figure 3: Color Rank according to Amount of Inulin

Rating Scale:

Table 4: Number of People per Specified Texture Rank


Texture Rank # of People/Specific Texture

Rank 1: Least Gritty 19 0 0 0 2 0 18 0 2 3 0 0 14 8 4: Most Gritty 0 1 5 9

0

5

10

15

20

0 10 20 30# of Peo

ple pe

r Specific Texture

Rank

Amount Inulin (g)

1: Least Gritty

2

3

4: Most Gritty

Figure 4: Texture Rank According to Amount of Inulin

Table 5: Number of People per Specified Sweetness Rank Amount Inulin (g) 0 g 10 g 20 g 30 g

Sweetness Rank # of People/Specific Texture

Rank 1: Most Sweet 14 1 2 2 2 2 12 3 2 3 0 6 10 3 4: Least Sweet 3 0 4 12

0

2

4

6

8

10

12

14

16

0 10 20 30

# of Peo

ple pe

r Specific

Sweetness Ra

nk

Amount Inulin (g)

1: Most Sweet

2

3

4: Least Sweet

Figure 5: Sweetness Rank According to Amount of Inulin

Table 6: Number of People per Specified Preference Rank


Preference Rank # of People/Specific Preference

Rank 1: Most Preferred 17 1 0 1 2 1 12 6 0 3 0 6 8 5 4: Least Preferred 1 0 5 13

0

2

4

6

8

10

12

14

0 10 20 30

# of Peo

ple pe

r Specific Preferen

ce

Rank

Amount Inulin (g)

1: Most Preferred2

3

4: Least Preferred

Figure 6: Preference Rank According to Amount of Inulin

Table 7: Number of People per Specified Preference w/Cookie Rank


Preference Rank # of People/Specific Preference

Rank 1: Most Liked w/Cookie 13 4 0 3 2 3 12 4 0 3 2 2 12 3 4: Least Liked w/Cookie 1 1 3 13

0

2

4

6

8

10

12

14

0 10 20 30

# of Peo

ple pe

r Specific Preferen

ce

w/Coo

kie Ra

nk

Amount Inulin (g)

1: Most Liked w/Cookie2

3

4: Least Liked w/Cookie

Figure 7: Preference w/Cookie According to Amount of Inulin

References

AllRecipes.com. Chocolate Cornstarch Pudding page. Available at: http://allrecipes.com/Recipe/chocolate-Cornstarch-Pudding/Detail.aspx#nutri-box. Accessed Sept. 27, 2008. American Heart Association. The Fiber page. Available at: http://www.americanheart.org/presenter.jhtml?identifier=4574. Accessed Sept. 27, 2008. Cargill Health and Food Technologies. The Oliggo-Fiber Inulin and Oligofructose page. Available at: http://www.cargillhft.com/industry_products_inulin.html. Accessed Sept. 27, 2008.

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Clausi AS, inventor; General Foods Corp., assignee. 1957 Aug. 6. Pudding composition and process of producing the same. U.S. patent 2,801,924.

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Hunter BT. 2003. Inulin: a beneficial carbohydrate. Consumers’ Research Magazine 86 (3): 8

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Orafti wins innovative prize. Foodnavigator.com: Breaking news on food and beverage development—Europe [serial online]. Aug. 2003. Available at: http://www.foodnavigator.com/Science-Nutrition/ORAFTI-wins-innovative-prize. Accessed Nov. 21, 2008.

Roberfroid MB. 2005. Introducing inulin-type fructans. British Journal of Nutrition 93:S13-S25. Tarrega A, Costell E. 2006. Effect of inulin addition on rheological and sensory properties of fat-free starch-based dairy desserts. International Dairy Journal 16 (9): 1104-1112.

Tseng, Y-C, Xiong YL, Boatright WL. 2008. Effects of inulin/oligofructose on the thermal stability and acid-induced gelation of soy proteins. Journal of Food Science E: Food Engineering and Physical Properties 73 (2): E44-E50.