“The Effects of Using Avocado Puree as a Fat Replacement on the Sensory Qualities of Oatmeal

Cookies”

By: Michelle Eckler, Marisa Hitchcock, & Jordan Lidstone

FOOD 230-01Fall 2013

I. Abstract:

In the United States, there is a lot of concern over the high rate of overweight and obese

children and adults in the population. The health risks of being overweight and obese, such as

diabetes, heart disease, and certain cancers, are well-known (“Do You Know Some of the Health

Risks of Being Overweight?,” n.d.). With this, it is essential to find ways to limit the amount of

fat consumed. One way this can be done is by using fat replacers in food products to eliminate

unnecessary fats from the diet. In this study, avocado puree was substituted for 50, 75, and 100%

of the butter in oatmeal cookies in order to create a more health-conscious alternative. The

control recipe was also made. The researchers were specifically looking for its effects on

physical, textural, and sensory properties of the cookies. They believed that the extent to which

the taste testers found the cookies appealing depended on the amount of butter replacement in

each product. Thirty consumers evaluated each cookie for appearance, color, taste/mouth feel,

moistness, and acceptability with a hedonic scorecard. Based on their scores, it was determined

that fat replacement of 75% of avocado puree was the most accepted by testers. No large

differences were apparent between the experimental and control groups. The control group was

rated the best color, 50% replacement had the most favorable appearance, 75% replacement had

the best taste/mouth feel and the highest overall acceptability, and 100% replacement was

determined to have the best degree of moistness. However, color and moistness were the only

categories in which a large difference was seen between the fat replacement cookies and the

control group. The control group had the most appealing color while 75 and 100% had the least

appealing. On the other hand, 100% avocado substitution had the most acceptable moistness

while the control group had the least acceptability in that area. The results of this study

demonstrate that cookies with 75% fat replaced with avocado will have acceptable physical,

textural, and sensory characteristics. The overall change in fat content from the control cookie to

the cookie made with 75% avocado puree was 4.7 grams (8.77 grams to 4.07 grams), a 54% fat

reduction. Therefore, a cookie made with avocado puree as a fat replacement can be called a

reduced-fat product and can help people cut down on unnecessary calories and lipids in their

diet.

II. Introduction:

In the United States there is a lot of concern about the rising rates of obesity in both

adults and children. Between 1980 and 2000, obesity rates doubled among adults. Presently,

about 30% of adults, or 60 million Americans, are classified as obese. Similarly, overweight

rates have doubled in children and tripled in adolescents since 1980 (“Facts About Obesity in the

United States,” n.d.). Part of the reason behind the rising rate is that adults and children alike are

consuming too much fat in their diet. A high-fat diet can heighten one’s risk of gallstones, type 2

diabetes, high blood pressure, high cholesterol, heart disease, stroke, and many more (“Do You

Know Some of the Health Risks of Being Overweight?,” n.d.) This makes it even more

imperative to discover new ways to cut back on caloric content in foods. One way to do that is by

replacing fat with a substitute in baked products that typicallys contain a lot of fat. The number

of fat replacements available and their use has continually increased in the food industry to meet

consumers’ demand for low-fat products that are still delicious (Brown, 2011).

Fat replacement in foods, especially baked goods, poses a complex problem because fat

contributes a large amount of sensory and physiological characteristics such as appearance,

color, odor, taste, mouth feel, moistness, and texture to the overall quality of the product. This

makes it very difficult to find a supplement that will match these critical attributes in order to

achieve a more healthful outcome. Recently, research has focused on making reduced-fat food

products taste better and have higher acceptance rates. Cookies are a common snack food in the

United States because of their long shelf life, convenience, and taste. Unfortunately, this baked

good is high in fat. Reducing fat in this product would alter the appearance, flavor, texture, and

smell provided by fat that are difficult to simulate in fat replacers. Fruit purees, including plum,

date, apple, and fig purees, have been used and are widely accepted as partial fat replacements

for baked products (Brown, 2011).

The avocado is a fruit well-known for its forest green and rough leathery skin as well as

its buttery texture. This makes it an ideal prospect for replacing butter in a recipe. Additionally,

the avocado has a pleasing taste and is loaded with monounsaturated fats and phytochemicals.

Avocados are also packed with vitamins, minerals, and other nutrients including fiber,

potassium, vitamin C, vitamin K, folate, and vitamin B6 (Thompson, 2011). The oils found in

avocados can also help to reduce cholesterol and prevent heart disease because the

monounsaturated fat found in avocados can lower LDL cholesterol, the “bad” cholesterol, and

help to maintain HDL, the “healthy” cholesterol (“Using Avocado as a Healthy Butter

Substitute,” 2013). This fruit is found in spreads, dips, salads, or on a sandwich or burger so

many people are aware of this functional food and its characteristics. Avocado puree has been

used as a substitute for butter, mayonnaise, and even cream cheese (“Using Avocado as a

Healthy Butter Substitute, 2013”). It is actually believed that European sailors used avocados in

place of butter on their trip to the New World. Avocados for sale in supermarkets in the United

States today mainly come from California and Florida.

A study was initiated to look into the performance of avocado puree as a fat replacer in

oatmeal cookies. It was also taken into account the similarities and differences of oatmeal

cookies made with just butter (the control). This study had avocado substitution of butter by 50,

75, and 100% replacement. Appearance, color, taste (mouthfeel), moistness, and overall

acceptability of each sample was evaluated by a team of 30 taste testers. If found pleasing, the

cookies made with avocado could be marketed as “reduced-fat” products.

III. Literature Review:

1. Article 1: “Optimization of a Sponge Cake Formulation with Inulin as Fat Replacer:

Structure, Physicochemical, and Sensory Properties”

Diets of people living in developed countries are often too high in calories and too low in

fiber. This has led to an increase in nutrition-related diseases and the recommendation that

people consume less fat and more complex carbohydrates. As a result, the food industry is

introducing new ways to replace the fat in foods. One fat replacement they are using is dietary

fiber. A study was conducted to analyze the structural, physicochemical, and sensory properties

of sponge cake when inulin was used as a fat substitute for sunflower oil. Inulin replaced

sunflower oil in increments of 35%, 50%, 70%, and 100% (these are the independent variables in

the study). Dependent variables in the study included structural, physiochemical, and sensory

characteristics. Sensory characteristics that were judged included appearance, texture, color, taste

acceptability, and overall acceptability of the cakes. Some of the results that were found included

that cakes made with a 0%, 35%, and 50% replacement level were softer; however, the cake

made with 100% inulin was significantly harder than the control. The sensory acceptance ratings

for the control cake and the cakes made with 35%, 50%, and 70% fat replacements did not vary

significantly. However, the cake made with 100% inulin ranked significantly lower in all of the

sensory characteristics. The overall conclusions from this study showed that sponge cakes made

with up to a 70% oil replacement did not have any significant differences from the control cake.

This implies that inulin can be used as fat replacement in cakes to make high-quality cakes that

can be labeled as reduced-fat by FDA standards (Rodriguez, Puig, Salvador, & Hernando, 2012).

2. Article 2: “Impact of Lentil Fortification on Physical, Chemical, and Instrumental Properties of Dough and its Influence on overall Quality of Cookies”

It is recommended by public health organizations that people cut 30% or more of their fat

consumption each day. However, fat plays a key role in food products. It creates a soft texture,

appealing mouth feel, a nice-looking appearance, and a good flavor and aroma. Some legumes

are appropriate for use in baked goods. Lentils, a type of legume, are known to have many health

benefits including decreasing cholesterol and blood pressure. A study was conducted to observe

the impact of using lentil flour as a fat replacement in soft dough cookies. Lentil flour replaced

fat (shortening) in the study in increments of 10%, 20%, 30%, 35%, 40%, 45%, and 50%. The

cookies were then evaluated on their physical properties and chemical properties. Sensory

qualities, including surface-color, appearance, texture, taste, and mouth feel, were judged as

well. It was found that moisture content of the flour decreased when lentil flour was increased,

but overall change was small. Hardness and protein content both increased with an increase in

the percentage of lentil flour. An increase in the use of lentil flour led to a decrease in fat content

which caused an increase in the diameter of the cookies. There were not many significant

differences in sensory factors; however, all parameters decreased with 50% lentil flour

substitution. In conclusion, the quality of the cookies made with lentil flour was close to that of

cookies made with fat. Lentil flour can be used as a fat replacement by adjusting other factors in

the recipe. Using lentil flour as a fat replacement in cookies also creates a cookie that is

nutritionally superior (Ashraf et al., 2012).

3. Article 3: “Consumer acceptability of chocolate chip cookies using applesauce as a fat (butter) substitute”:

Many of the foods produced in the United States today, including cookies, are plagued

with unhealthy fats that are detrimental to the human body. Replacing these unhealthy fats with

fruit puree substitutes such as applesauce would help to decrease the fat intake from these

cookies and increase the intake of healthy foods such as fruits. The purpose of this study was to

determine the acceptability of applesauce in cookies as a fat replacement for butter. Three

sample recipes were conducted all yielding different percent’s of applesauce in replacement for

butter. The first recipe was made without applesauce; the second was made with fifty percent

butter and fifty percent applesauce, while the third recipe was a complete replacement of

applesauce for butter. A group of thirty five consumers rated the recipes based off of many

different characteristics. These characteristics included, color, sweetness, flavor, texture,

appearance, chewiness, and the acceptability of the product overall. Many of the tasters found

that they liked the regular recipe and the half replacement recipe at similar levels, while the full

replacement recipe fell behind in all aspects of the characteristics tested. Concluding this

experiment it can be stated that applesauce, a fruit puree, is an acceptable fat substitute, but only

up to half replacement by the preferences of the consumers. By replacing butter/unhealthy fats

with applesauce the nutritional levels of chocolate cookies will increase. (Hayek & Ibrahim,

2013).

4. Article 4: Effects of Avocado Puree and Oatrim as Fat Replacers on the Physical, Textural, and Sensory Properties of Oatmeal Cookies:

In this study, avocado puree and Oatrim were substituted for 25, 50, and 75% of the

butter fat in oatmeal cookies in order to discover a more health-conscious alternative. It was

determined that fat replacement of 50% for both the avocado and Oatrim were the most enjoyed

by testers. No accountable differences were apparent between the experimental and control

groups in color, tenderness, sweetness, flavor, or aftertaste. When compared to the cookies in the

control group, both substitution cookies had more rise, increased amounts of moisture loss, and

heightened water activities. The experimental cookies were also tougher and less brittle.

However, appearance was the only category in which a large difference was seen between the fat

replacement cookies and the control group. The results of this study demonstrate that cookies

with 50% fat replaced with avocado or Oatrim will have acceptable physical, textural, and

sensory characteristics. The overall change in fat content from the control cookie was 35% less

for avocado and 39% for Oatrim. Foods made with partial fat replacers can make more healthful

and reduced-fat meals that will help people cut down on unnecessary calories and lipids in their

diet. In this study avocado puree was paired with oatrim as a fat replacement and was successful

at the 50% replacement level (Wekwete & Navder, 2008).

5. Article 5: “Effect of Corn Bran as Dietary Fiber Addition on Baking and Sensory Quality”:

One large concern in this country is the lack of fiber in a typical American’s every day

diet. The lack of adequate fiber in the diet can cause many diseases like diverticulosis, colon

cancer, diabetes, heart disease, and many more. Incorporating fiber, like corn bran, into an

assortment of foods is one way in which one’s nutrition and overall health can be improved. The

purpose of this study was to find the effects that corn bran has on the baking quality in cake and

cake-like products. Corn bran was substituted for 0, 5, 15, 20, 25, and 30% of the flour in cakes

to increase dietary fiber. It was found that the elasticity of batter decreased as the proportion of

corn bran increased due to water absorption by corn bran. Also, the viscous modulus decreased

with an increase of corn bran. There was a significant amount of water lost in batters containing

more than 15% corn bran. The analysts concluded that a maximum of 20% replacement with

corn bran in cake was an acceptable amount without losing quality, processability, and

acceptability. These findings suggest that cake-like products can be enhanced in fiber quantity to

create more healthful products (Singh, Liu, & Vaughn, 2012).

6. Article 6: “Effect of Fat Replacement on Sensory Attributes of Chocolate Chip Cookies”:

Diets that are rich in fat and low in fiber and carbohydrates have been associated with

serious health conditions such as heart disease, obesity, liver dysfunction, and cancer. It is

recommended that fats constitute 30% or less of total daily energy intake so some consumers are

choosing to purchase and eat snacks that have a reduced fat content. In this study, three fat

replacements were tested in chocolate chip cookies: Gerber prune, Wonderslim brand fat and egg

replacement, and Oatrimbrand fat replacement. The control batter was Crisco butter-flavor

shortening as the fat. The results were found to be that Oatrim scored the worst in the sensory

attributes of appearance, color of surface, texture, tenderness, and flavor. The control, on the

other hand, had the best scores of all groups for all of the sensory attributes. In addition, the

Oatrim group had the worst overall acceptability score whereas the control group had the best.

The prune paste and Wonderslim replacements groups exhibited similar scores for most of the

attributes. By purchasing cookies made with the fat replacements considered in this study,

consumers can reduce fat consumption by nearly 70%. (Charlton & Sawyer-Morse, 2010).

IV. Hypothesis:

By replacing a portion or all of the fat from butter with avocado puree in oatmeal

cookies, we hypothesize that we will be able to create cookies that are overall acceptable, while

increasing the nutrient quality and reducing the fat content of them. We hypothesize that all of

our cookies made with avocado puree (50%, 75%, and 100% replacement levels) will all be

found acceptable.

V. Methodology

A. Research Design: an overall structure of the whole research process

The overall design of this experiment was based around a reliable oatmeal cookie recipe

received from allrecipes.com. The purpose of the experiment was to see if avocado puree can be

used as a successful fat replacement in the cookies. A control group, a 50% replacement sample,

a 75% replacement sample, and a 100% replacement sample were made and tested. A team of

four entered the lab and prepared all four recipes at once. After combining the ingredients

following the recipe directions, the pre-baked products were placed onto parchment paper which

was placed onto cookie sheets (all thin and light colored cookie sheets). The idea of avocado

puree as a fat replacer was to increase the nutritional value of this product and decrease the level

of unhealthy fats in the product. The pursuit of this experiment was to determine which level of

fat replacement is most accepted by consumers in all aspects of appearance; taste (mouth-feel),

moistness, color, and overall acceptability. There was 30 taste testers that consumed each sample

and completed a survey upon testing. The survey results were then used to determine which fat

replacement level ranked the best in each category.

B. Products, Variables, and Measurements

The products included four different samples of oatmeal cookies each using different

percentages of fat (unsalted butter) and avocado puree (as a fat replacement). The first sample

was the control group which contained one hundred percent of unsalted butter (no avocado

puree). The second sample had fifty percent butter and fifty percent avocado puree. The third

sample had twenty-five percent butter and seventy- five percent avocado puree. The fourth and

last product had one-hundred percent avocado puree. The independent variable is the percentage

of avocado puree being used as a replacement: 0%, 50%, 75%, and 100%. The dependent

variables include appearance, taste (mouth-feel), moistness, color, and overall acceptability. The

surveys used were based off of a scale of 1-5, ranging from a score of 1 meaning strongly

disagree and 5 being strongly agree. A score of 2 indicated disagree, a score of 3 is neutral, and a

score of 4 means agree.

C. Procedures of Experiment

The procedures were simple in constructing this experiment. Four different recipes were

constructed in the exact same fashion at the same time by each group member.

The Control Recipe:

½ cup of softened butter

½ cup white sugar

½ cup packed brown sugar

1 egg

½ tsp. vanilla extract

1 cup all-purpose flour

½ tsp. baking soda

½ tsp. salt

¾ teaspoon ground cinnamon

1 ½ cups quick cooking oats

1) Cream together butter white sugar and brown sugar. Beat in egg and then stir in

vanilla. In a separate dish combine the dry ingredients flour, baking soda, salt,

cinnamon, and slowly stir into the wet ingredient mixture.

2) Preheat the oven to 375° and place parchment paper on cookie sheets, roll the

dough into walnut sized balls

3) Bake for 11 minutes

For the 50% replacement substitute, ¼ cup of the butter was creamed with ¼ cup of

pureed avocado in place of the ½ cup butter. The mixing procedures were the same as the

control and these cookies also took about 11 minutes to bake.

For the 75% replacement, 3/8 cup avocado puree was creamed with 1/8 cup butter in

place of the ½ cup butter. The mixing procedures were the same. These cookies took 12

minutes to bake.

For the 100% replacement, the ½ cup of butter was completely substituted with ½ cup

avocado puree. The mixing procedures were the same and these cookies took 13 minutes

to bake and still had a slightly mushy texture after baking.

D. Instrument/Questionnaire Design

The survey used was a construction of five questions all based on the dependent

variables. The scale included choices 1-5, one being that you strongly disagree, two being you

disagree, three being neutral, four being you agree, and five is that you strongly agree. There

was also a space for participants to write in an explanation if they did not like the sample.

Sample #_____

1. The appearance is acceptable 1 2 3 4 5

2. The color is appealing 1 2 3 4 5

3. The taste/ mouth feel is acceptable 1 2 3 4 5

4. Acceptability of moistness 1 2 3 4 5

5. Overall Quality is acceptable 1 2 3 4 5

If you did not like the sample, please explain why;

E. Survey Participants: how and why do you select them, backgrounds,

numbers

Number of survey participants: 30

25 of the 30 survey participants were selected from a food science class while the other five were

random taste testers for our experiment. They were selected based off of convenience and time

availability. Many of the taste testers have backgrounds in nutrition courses and food service

experience, while few to none have no background in these categories at all. Two of the taste

takers had extensive backgrounds in food science and food preparation. Most were in the age

range of 18-24, with two of them being over the age of 30.

F. Survey Administration: procedure of survey

The survey was placed next to sample one for the survey participants to take and begin

with sample one followed by two, three, and then four. Upon completion of all the samples, the

surveys were handed to one of the group members and tucked away to avoid pressure on the

participants in their answer choices. Participants came over when they were not tasting other

samples and most, if not all, were oblivious to the specific fat replacer used.

G. Data Analysis

After tallying up the surveys, a very profound result was concluded. The results for

every sample and every variable in question were very close. No average fell below 3.1 and no

average above 4.4. This makes every sample acceptable in every area that was rated by the

survey takers. The data is displayed below:

N= 30 Sample 1 Sample 2 Sample 3 Sample 4

The appearance is acceptable

4.2 4.3 3.8 3.9

The color is appealing

4.4 4.2 3.7 3.7

The taste/ mouth feel is acceptable

4.0 3.8 4.1 3.6

The moistness is acceptable

3.1 3.6 4.0 4.3

The overall quality is acceptable

3.97 3.7 4.1 3.8

VI. Results

A. Response rate of survey and participants profile

We were able to gather enough participants to gather data from 30 different taste testers,

which was the amount of taste testers we needed. The overall age group of the survey

participants falls between 18-23 years old, all most of which are majoring in dietetics or food

service, all of which are college students or professors. Two of the participants were over the age

of 30 and are foodservice or food science professors. The entire sampling process for each

participant took about 5-7 minutes between tasting the samples, rinsing their mouths with water

and moving on to the next sample.

B. Data descriptions, reject or support of hypotheses

The overall data did not vary as much as was expected. Our hypothesis was supported.

Our hypothesis was supported because all of the samples were rated as acceptable (score of 3.0

or above). The 75% replacement of butter with avocado puree was the most accepted sample. It

pulled ahead of the control recipe with no avocado and all butter in terms of overall

acceptability. The overall acceptability between all the samples only varied by .4 proving that all

samples were across the board accepted almost just as much as one another. Sample one was

commonly the most appealing in terms of color and sample two was voted for the best

appearance. For mouth feel and taste, sample three pulled ahead for the most liked. Sample four

had the most desired moistness. For overall acceptability, sample three ranked ahead of the other

samples. The data here is all over the place and the degree of variation is very small proving

once again that avocado is an acceptable replacement in this recipe.

C. Chart, Figures, and/or Tables:

Yield= 1 dozenServing size= 1 cookie

Sample 1 Sample 2 Sample 3 Sample 4

Calories 217.6kcal 191.4kcal 178.2kcal 165.1kcal

Calories from fat

78.93 kcal 50.76 kcal 36.63 kcal 22.5 kcal

Total Fat 8.77g 5.64g 4.07g 2.5g

Saturated Fat 5.1g 2.77g 1.6g .44g

Cholesterol 35.85g 25.68g 20.59g 15.51g

Total Carb. 32.13g 32.53g 32.73g 32.94g

Sodium 159.76mg 159.58mg 159.98mg 159.39mg

Fiber 1.35g 1.67g 1.83g 1.99g

Protein 3.25g 3.31g 3.33g 3.36g

Survey Results (N=30)

Calories and Calories from fat

Sample 1

contro

l group

Sample 2

50% replac

emen

t

Sample 3

75% replac

emen

t

Sample 4

100% replac

emen

t0

50

100

150

200

250

CaloriesCalories from fat

Sample 1 Sample 2 Sample 3 Sample 40

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

4.2 4.3

3.8 3.9

4.44.2

3.7 3.74

3.84.1

3.6

3.1

3.6

44.3

3.973.7

4.13.8

AppearanceColorTaste/ mouth feelMoistnessOverall quality

Treatment % Fat (Butter) % Avocado

1 100% (1/2 cup) 0

2 50% (1/4 cup) 50% (1/4 cup)

3 25% (1/8 cup) 75% (3/8 cup)

4 0 100% (1/2 cup)

Control group: 50%:

Sample 1 Control group

Sample 2 50% replacement

Sample 3 75% replacement

Sample 4 100% replacement

0

1

2

3

4

5

6

7

8

9

10

Fat difference in samples (g)

Fat

75%: 100%:

VII. Discussion:

The four different cookie samples made with different percentages of avocado puree as a

fat replacement all had different characteristics. However, the different cookies did not differ

greatly in quality aspects, but did differ quite a bit nutritionally. All four cookies samples had an

overall acceptability that was 3.7 or higher, which implies that all of the cookies were overall

acceptable. All of our samples rated 3.1 or higher in all categories: appearance, color, taste

(mouth feel), moistness, and overall quality; which means all of our cookies were acceptable in

all categories scored. This implies that avocado puree can successfully be used as a fat

replacement in oatmeal cookies. A previous study had shown that avocado puree was an

effective fat substitute at a 50% substitution (Wekwete & Navder, 2008). Through our

experiment, it was shown that oatmeal cookies made with 50%, 75%, and 100% fat replacement

with avocado pure all had acceptable ratings showing that avocado puree, a fruit puree, can be an

acceptable fat substitute up to 100% substitution.

When it came to individual quality characteristics, sample two had the highest rating in

terms of appearance with a score of 4.3. Sample one was in a close second with a score of 4.2.

Sample 1 had the highest rating for color. Sample one had a nice, golden brown color. As the

percentage of avocado puree increased in the samples, the samples become increasing green in

color with sample four having a medium green color. The green tint to the cookies from the

avocado puree was the reason why the cookies look less appetizing and less aesthetically

pleasing in terms of color. This is more than likely the reason why the color acceptability rating

decreased as more avocado puree was used. This is shown by the decreasing rating in

acceptability of color from a 4.4 rating for the control (sample one) to a 4.2 rating for sample two

(50% avocado puree) to 3.7 for both sample three (75% avocado puree) and sample four (100%

avocado puree).

The acceptability of taste (mouth feel) for our samples varied and did not show a clear

pattern. Sample three (75% avocado puree) had the highest rating for acceptability of taste

(mouth feel) with a rating of 4.1. Sample one had the second highest rating with a score of 4.0.

Sample two had the third highest rating with a score of 3.8 while sample three had the lowest

rating with a 3.6. All of the samples rated above a 3, which means they were all acceptable in

terms of taste (mouthfeel). Avocado puree can effectively be used as a fat replacement that still

produces a cookie with an overall acceptable taste (mouth feel). Avocado pure is classified as a

fat substitute because it is lipid based. Therefore, in the experiment avocado puree was

substituted on a one-to-one ratio for butter. As a fat substitute, avocado puree is able to duplicate

many of the functional properties of fat (Brown, 2011). Avocado puree as a fat replacement adds

both softness and chewiness to bake products, both of which are desirable qualities in cookies

and are both functions of fats in baked goods. It is also hard to distinguish any avocado flavor in

baked products, such as oatmeal cookies, made with avocado puree as a fat replacement; this fact

helps to maintain an overall acceptable taste (mouth feel).

As the percentage of avocado puree used increased in our samples, the rating for

moistness also increased. Sample one (the control) had scored a 3.1 for the acceptability of the

moistness of the cookie. Sample two scored a 3.6 while sample three scored a 4.0. Sample four,

the cookie made with 100% avocado puree, received the highest rating for moistness with a score

of 4.3. Avocado puree does add moistness to cookies because it does contain a high amount of

fat and fat helps to add moisture to baked products. However, the baking time could have also

affected the moistness of the cookie samples. Although sample four had the longest baking time,

it still came out slightly mushy. The use of avocado puree could have affected the baking time of

the cookie, which could explain why the samples made with avocado puree took longer to bake.

From our experiment, it was determined that that baked goods, such as cookies, made with

avocado puree may need to be cooked for a longer baking time compared to baked goods made

with butter to achieve the same level of doneness. The control recipe may have been baked too

long because the cookie was very crisp after baking and not very moist. It was also noted that the

use of avocado puree as a fat replacement influenced the structure of the dough. As the

percentage of avocado puree in the cookie dough increased, the dough seemed to become thinner

and moister. The control recipe dough was the hardest to mix because it was drier.

The use of avocado puree has a butter replacement had significant effects on the nutrition

information of the cookie. There is a significant nutritional difference between butter and fresh

avocado puree. Two tablespoons of butter has 204 calories, 23 grams of fat, 14.6 grams of

saturated fat, and 61 mg of cholesterol while two tablespoons of fresh avocado only has 50

calories, only 4.5 grams of fat, 0.5 grams of saturated fat, and no cholesterol. The control recipe

made with 100% butter had the highest caloric value, fat content and saturated fat content as well

as the highest amounts of cholesterol. Compared to the control recipe, the recipe made with

100% avocado puree had approximately 53 calories, 6.27 grams of fat, 4.66 grams of saturated

fat, and 20.34 mg of cholesterol less per cookie. Although this may not seem like a huge

difference, if a person was to eat one oatmeal cookie a day for a year made with avocado puree

in place of butter instead of their usual cookie, they would save 19, 345 calories a year which

equals approximately five and a half pounds. Simple measures such as swapping the butter in

cookies for avocado puree can make a difference and help fight the obesity epidemic that

America is facing today.

VIII. Conclusion:

Our findings showed that avocado puree can be acceptably used as a fat replacement in

oatmeal cookies, all the way up to 100% replacement. However, appearance and color both

decline in acceptability as the percentage of avocado puree substituted for butter increases.

Overall acceptability and taste (mouth feel) both showed no clear trend in correlation to the

percentage of avocado puree used. Our hypothesis was correct; all of the cookies made with

avocado puree were found to be acceptable. The 75% fat replacement cookies scored the highest

in terms of overall acceptability, even higher than our control cookie. This surprised us because

we thought the control cookie made with 100% butter would be rated as the best in overall

acceptability because it is what people are used to.

Through our experiment, we were able to show that avocado puree can be used as a

successful fat replacement in oatmeal cookies with a replacement of even 100% showing

acceptable quality ratings. Avocado puree is a successful fat replacement for oatmeal cookies

that not only helps to reduce total fat content in the cookies, but also calories, cholesterol, and

saturated fat, providing for a much healthier cookie. The replacement of butter by avocado puree

in cookies is one way to make a more nutritional (lower fat, lower caloric content, etc.) cookie

which can help to fight the obesity epidemic the United States is facing. People would still be

able to enjoy one of their favorite cookies, but with a decreased total fat, saturated, and calorie

content. An excess intake of all three (total fat, saturated fat, and caloric content) can lead to

obesity and chronic diseases.

The most accepted recipe (the cookie with the highest overall acceptability rating) is

below: It is the 75% avocado pure and 25% butter oatmeal cookie.

Avocado Oatmeal Cookies:

3/8 cup pureed avocado

1/8 cup of softened butter

½ cup white sugar

½ cup packed brown sugar

1 egg

½ tsp. vanilla extract

1 cup all-purpose flour

½ tsp. baking soda

½ tsp. salt

¾ teaspoon ground cinnamon

1 ½ cups quick cooking oats

1) Cream together butter, avocado, white sugar and brown sugar. Beat in egg and then stir

in vanilla. In a separate dish combine the dry ingredients flour, baking soda, salt,

cinnamon, and slowly stir into the wet ingredient mixture.

2) Preheat the oven to 375° and place parchment paper on cookie sheets, roll the dough into

golf ball sized balls

3) Bake for 10-12 minutes

IX. Application/Implication and Future study

The best sample is sample three, the recipe using 3/8 of a cup of pureed avocado and 1/8 a

cup of butter which is a 75% fat replacement. Although all the samples were very close in the

final tally, sample three had the highest rating for overall acceptability. The taste (mouth feel) of

sample three was also the most desired in the results. Sample three ranked second in moistness.

However, all three levels of substitution (50%, 75%, and 100%) all produced cookies with

acceptable ratings, showing that avocado puree is a successful butter replacement in oatmeal

cookies. An application of this experiment is that avocado puree can be used in place of butter,

all the way up to 100% replacement, when making cookies and will produce a cookie that is not

only still acceptable, but also has a decreased calorie, sodium, and cholesterol contents. The

cookie made with avocado puree is also more nutrient dense because avocado adds healthy fats

(monounsaturated) and essential vitamins (including vitamins A and E) as well as more dietary

fiber.

If a future study were conducted, a suggestion would be to try a cookie with more ingredients

to see if the moisture and texture were altered any more than was recorded here and if the

amount of flavor by ingredients has to do with the change in results. A second study could also

be conducted to look into the affects that avocado puree as a fat replacement has on the baking

time and temperature of cookies compared to when the cookies are made with all butter.

X. Limitations:

Some limitations to our experiment is that we did not have a cookie scoop available to

make a uniform cookie size; therefore we had to use our hands to shape and mold the cookies.

This made for slight differences in the sizes of our cookies which could have affected the overall

texture and shape of our different cookie samples. A second limitation to our experiment was

that the cookies made with avocado puree in place of butter were noticeably greener than our

control cookies. This could have given away which cookies were which to our taste takers which

could have influenced their overall perception of our cookies. A third limitation to our

experiment was that our taste takers were for the most part of only one age group, around the

ages of 18-22. Out of 30 respondents, only about two were above the age of 30. Results could

have varied differently if we had a wider age range for our taste takers.

XI. References:

Ashraf, S., Muhammad, S., Saeed, G., Sayeed, S., Kanwar, H., Ahmed, M., et al. (2012). Impact of Lentil Fortification on Physical, Chemical, and Instrumental Properties of Dough and its Influence on overall Quality of Cookies. The Arab Gulf Journal of Scientific Research, 30, 125-134.

Brown, A. C. (2011). Understanding food: principles and preparation (4th ed.). Belmont, CA: Wadsworth Pub Co.

Charlton, O., & Sawyer-Morse, M. (2010). Effect of fat replacement on sensory attributes of chocolate chip cookies. 96(12), 1288-1290.

Do You Know Some of the Health Risks of Being Overweight?. (n.d.). WIN. Retrieved November 27, 2013, from http://win.niddk.nih.gov/publications/health_risks.htm

Facts About Obesity in the United States. (n.d.). Centers for Disease Control and Prevention. Retrieved November 21, 2013, from http://www.cdc.gov/pdf/facts_about_obesity_in_the_united_states.pdf

Hayek, S., & Ibrahim, S. (2013). Consumer acceptability of chocolate chip cookies using applesauce as a fat (butter) substitute. Emirates Journal of Food and Agriculture, 25(3), 159-168.

Rodriguez-Garcia, J., Puig, A., Salvador, A., & Hernando, I. (2012). Optimization of a Sponge Cake Formulation with Inulin as Fat Replacer: Structure, Physicochemical, and Sensory Properties. Journal of Food Science, 77, 189-197.

Singh, M., Liu, S., & Vaughn, S. (2012). Effect of corn bran as dietary fiber addition on baking and sensory quality. 1(4), 348-352.

Thompson, C. (2011, June 11). 8 Healthy Facts about Avocados: Calorie Information, Varieties, and More. WebMD. Retrieved November 16, 2013, from http://www.webmd.com/diet/features/8-healthy-facts-about-avocados

Use Avocado as a Healthy Butter Substitute. (n.d.). California Avocados Direct. Retrieved November 16, 2013, from http://www.californiaavocadosdirect.com/13/use-avocado-as-a-healthy-butter-substitute.aspx

Wekwete, B., & Navder, K. P. (2008). Effects of avocado fruit puree and Oatrim as fat replacers on the physical, textural and sensory properties of oatmeal cookies [electronic resource]. Journal Of Food Quality, 31(2), 131-141.