the effect of sugar, stevia, splenda, and sweet n’ low on...
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The Effect of Sugar, Stevia, Splenda, and Sweet N’ Low on the Shelf Life of a Pound Cake
Evalyn Neal Cooke and Charlotte Mae Jones 10th Grade
Heathwood Hall Episcopal School 3000 South Beltline Blvd.
Columbia, SC 29201
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Table of Contents
I. Abstract......................................................3
II. Introduction..............................................4
III. Materials.................................................6
IV. Methods..................................................7
V. Results......................................................8 VI. Conclusion..............................................12 VII. Acknowledgements...............................13 VIII. Works Cited.........................................13
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I. Abstract
THE EFFECT OF SUGAR, STEVIA, SPLENDA, AND SWEET N’ LOW ON THE SHELF LIFE OF A CUPCAKE
Evalyn Neal Cooke Charlotte Mae Jones
Heathwood Hall Episcopal School
The purpose of this experiment is to discover the effect of Stevia, Sweet N’ Low, Splenda and sugar on the shelf life of a mini pound cake. This is significant because if large manufacturers need to sell cakes, the information found in this experiment would be necessary for proper knowledge, precautions, and efficiency. The following hypothesis was utilized: if the cupcake is made with a sugar substitute then it will take longer to decompose compared to the cake made with refined sugar. Two trials were run, where the five independent variables−Refined Sugar, Splenda, Sweet N’ Low, Stevia, and Nothing−were placed in Biochambers with a carbon dioxide sensor, an oxygen sensor, and a thermometer. The carbon dioxide and oxygen sensors were attached to the Vernier Loggerpro software that automatically collected data every hour for five days. The temperature was collected manually once everyday. The data were averaged and analyzed showing that the hypothesis was rejected. The cupcake baked with sugar had the lowest decomposing rate. The results were analyzed using a one-way ANOVA test (alpha=0.05). Respectively, this test showed that the only statistically significant differences were found in the oxygen levels between the control and Splenda, and the control and Stevia. However, there was no statistically significant difference for change in both carbon dioxide, temperature, and oxygen levels for all other variables tested.
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II. Introduction Have you ever wondered how long you have to eat a cake? Sure, you can look up
on the Internet what the cake mix’s shelf life is, but what about the actual baked cake? In
this experiment the effects of sugar, Stevia, Sweet N’ Low, and Splenda will be on the
shelf life of a plain mini pound cake will be determined. The Independent variables were
chosen because they are the most well-known and most widely used substitutes. Sugar is
“sucrose, the white crystalline sugar refined from cane or beet juice by stripping away all
its vitamins, minerals, protein, fiber, water, and other synergists” (HPS-Online). White
sugar is a man-made product that causes the pancreas to secrete unnaturally large
amounts of insulin, which is needed to break down the sugars. Large sugar consumptions
will steal nutrients from other places in your body, causing a lack of nutrients, which can
be very harmful. Sugar is the backbone of many diseases today, one of the more serious
ones being diabetes. When consuming sugar, you should always regulate the amount of
intake into the body, but that also goes along with most man made products in the food
industry today, meaning that most, if not all processed foods can be very harmful to the
body. Sucralose, or Splenda, is a sugar replacement that has “678 fewer calories than a
cup of sugar”, so it is promoted as a better way to cook so that there are not as many
calories or carbohydrates as regular refined sugar (splenda.com). It is also used in a high
variety of places for cooking and baking. Sweet N’ Low, or more specifically called
saccharine, is also a commonly used granulated sugar substitute. An all-natural
substance, Stevia, is an herb used in either a powder or liquid form that is “30 times
sweeter than sugar” and is a “safe alternative” to sugar and synthetic sugars (stevia.com).
All sugar substitutes used are safe for diabetics. Diabetics can easily make these recipes,
so they can have a safe and healthy dessert without increasing their blood sugar.
Previous studies by Gelinas, Roy, and Guillet have shown that replacement of
natural cocoa sweetener with a highly processed cocoa powder slowed staling rate in
devil’s food cake (Food Science, 2008). Also, in that experiment, the use of high
concentrations of fats, sugars, and egg whites also slowed the staling rate. The staling rate
was measure by “studying the effects of packaging film water permeability and storage
temperature over time” (Food Science, 2008). The study also shows that staling can be
reduced slightly by using butter instead of shortening and to replace glucose with sucrose.
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This study is helpful to this project because it indicates that shelf life can be affected by
different ingredients that are taken out or replaced, just like in the experiment by Gelinas
and Guillet, the shortening was replaced with butter, and the glucose replaced with
sucrose. In the case of this project, the sugars are going to be interchanged.
The plain pound cake, serving as one of the many constants, is a basic recipe
found in the book, “Easy Recipes with 5 Ingredients or Less”, except one teaspoon of
vanilla will be implemented instead of the one tablespoon of orange juice. This simple
recipe will be used to keep costs low, and keep the other ingredients from affecting the
shelf life.
In this experiment, “shelf life” of the mini pound cake was tested. For the means
of this experiment, “shelf life” is defined as the amount of time it takes for a cake to
deteriorate, or come to a point where it is not sanitary to consume. In determining shelf
life, three tests will be run: CO2 test, and temperature probe test. Results will be collected
and the results will be turned into a rate, which will then be put into a graph.
A CO2 sensor, which will be used in the testing of the mini pound cakes, is a
sensor, which will be run through a PC computer, that measures carbon dioxide gas. The
most common principles of a CO2 sensor are the infrared gas sensor (NDIR) and
chemical gas sensor. For the purposes of this experiment, the chemical gas sensor will be
used (Cardiopulmonary Technologies, Inc., 2005). The CO2 sensor will help determine
the different factors that affect shelf life. The more CO2 found emitting from the cake, the
higher the presence of living microorganisms undergoing cellular metabolism on the
cakes. Kaplan and Reinhold have shown the relationship between CO2 and
microorganisms in their study of photosynthetic microorganisms (Plant Biology, 1999).
When measuring the CO2, the unit parts-per-million will be used for the amount of CO2
in the biochamber. Safe CO2 levels for a room can be range from around 5,000 ppm and
below.
A thermometer, which will also be used in the testing of the mini pound cakes, is
a device that measures the temperature through voltage across a diode. It is said that by
amplifying the voltage change, it is easy to generate an analog signal that is directly
proportional to temperature (Instructables, 2010). As the cellular metabolism on the
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mini pound cakes increases, the temperature in the environment should also
increase.
An O2 probe was used also because if the CO2 levels and the O2 levels have an
inverse relationship. For this experiment, the oxygen units were changed from
percentage to ppm.
A biochamber 1000, which the individual mini pound cakes will be stored in, is a
controlled environment for the testing of the cakes, which is important for the
experiment, so that no other factors affect the shelf life except for the sugar and sugar
substitutes.
This experiment is helpful in telling if it is still healthy and sanitary to eat a cake
that has been sitting out for a two week time period. It also helpful in determining
whether one sugar or sugar substitute in particular could be used over the other and which
prolongs or deteriorates the shelf life.
The purpose of this experiment is to determine the effect of Stevia, Sweet N’
Low, Splenda, and sugar on the shelf life of a mini pound cake. It is hypothesized that if
the pound cake is made with a sugar substitute then it will take longer to decompose
compared to the cake made with sugar; however, the null hypothesis is if the pound cake
is made with a sugar substitute then there will be no difference in the amount of
decomposition compared to the cake made with sugar.
III. Materials 1 oven 1 mixer 2 large mixing bowls 8 sticks of Butter 2 cups of sugar 12 eggs 8 cups of flour 4 tsp. of vanilla extract 2 cups of Splenda 2 cups of Stevia 2 cups of Sweet N’ Low 1 muffin tin 1 oven mitt 1 can of Pam
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5 Vernier O2 censors 5 Vernier CO2 censors 5 Learning Resources temperature probes 5 Cambro Biochamber 1000, Vernier 5 computers equipped with Logger Pro Software, Vernier IV. Methods Experimental Design Diagram: TITLE: The effect of Stevia, Sweet N’ Low, Splenda and sugar on the shelf life of a Pound cake. HYPOTHESIS: If the mini pound cake is made with a sugar substitute then it will take longer to decompose compared to the cake made with refined sugar.
This experiment had five different groups: Sweet N’ Low, Splenda, Stevia, Refined
Sugar, and the control was an empty Biochamber housing only the sensors and
thermometer. The following cake recipe was followed for all groups:
Preheated oven to 350 degrees, creamed two cups of sugar and 2 sticks of butter until
light and fluffy, added three eggs one at a time and beat after each addition, Stirred in two
cups of flour and one teaspoon of vanilla. Poured into greased and floured cupcake pan
(pan makes 12 cupcakes, but only four molds used). Baked for exactly 30 minutes. After
the four cupcakes had been baked, they were set on the counter and cooled for about 30
minutes.
Next, each cupcake was placed in a separate Biochamber on top of a paper towel,
IV: Sugar and Sugar Substitutes
Sweet N’ Low Splenda Stevia Refined Sugar Nothing (Control)
2 Trials 2 Trials 2 Trials 2 Trials 2 Trials
DV: Shelf Life as measured by rate of CO2 and O2 production, and temperature
Constants: basic cake recipe, experimenting environment, temperature at which cakes are cooked, time cakes are cooked in oven, container cupcakes are in (Biochamber 1000), distance of cake from sensors
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which had a carbon dioxide and oxygen sensor and a thermometer attached to the side.
The Vernier Loggerpro software automatically took samples of the current oxygen and
carbon dioxide levels of the cupcake. The software took samples every hour and
temperature was manually collected once everyday. Preceding the first trial, a second trial
was performed following the same procedures as above. Once the data of the two
separate trials had been collected, the means were taken from the data and calculated.
V. Results Table 1: Mean Carbon Dioxide Levels over 112 hours CO2 (ppm) Control Sugar Stevia Sweet N’
Low Splenda
0 hrs. 212.75 563.5 315.75 948 443.5 24 hrs. 229.75 252.5 681 981 482.5 48 hrs. 232.25 600 711 1039 487.5 72 hrs. 505.5 584.5 727 1023 502 96 hrs. 456 510.5 706 1009.5 433.5 112 hrs. 322 348 598 817 296.5
Figure 1: Mean Carbon Dioxide Levels vs. Time
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Table 1 and Figure 1 depict the mean carbon dioxide levels for the cupcakes
baked with sugar, Stevia, Sweet N’ Low, and Splenda, including a control. The highest
range was the Stevia cake with a range of 3.74, and the Sugar cake had the lowest range
with a range of 0.104. The mode was not applicable. The highest mean was the Stevia
cake with a mean of 0.776, and the Sugar cake with a mean of -0.552. the lowest median
was sugar cake with a median of -0.552, and the highest median was the Stevia cake with
a median of 0.776. The Stevia cake had the highest standard deviation at 2.64, and the
sugar cake had the lowest standard deviation at 0.074. The Sweet N’ Low cake has a
higher CO2 level throughout the entire trial than the rest of the sugar substitutes, showing
numbers in the 1000’s where none of the other mini pound cakes did. All of the carbon
dioxide levels were higher at the beginning of the data collection than the control was. A
trend occurs at 72 hours, when the carbon dioxide levels decrease. The sugar cake
dropped dramatically at 24 hours. At 112 hours, the control, sugar, and Splenda cakes all
decreased to around the same carbon dioxide level, but the Sweet N’ Low cake and
Stevia cake ended at higher levels than the rest. There was no statistically significant
difference (p>0.05) for change in the carbon dioxide levels between any of the variables
tested. The data above failed to reject the null hypothesis that if the mini pound cake is
made with a sugar substitute then it will not take longer to decompose compared to the
cake made with refined sugar, and the data did not support the hypothesis.
Table 2: Mean Oxygen Levels over 112 hours O2 (ppm)
Control Sugar Stevia Sweet N’ Low
Splenda
0 hrs. 16113.5 175489 197992.5 235061 206371 24 hrs. 160515 191584.5 195515 164043.5 203663.5 48 hrs. 159393.5 188441.5 193650.5 165054 201596.5 72 hrs. 160155.5 191011.5 194922 163151 202989 96 hrs. 161090.5 190499.5 194417 161374.5 101173.5 112 hrs. 159825.5 197281 196546.5 164662 204844
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Figure 2: Mean Oxygen Levels vs. Time
Table 2 and Figure 2 show the mean oxygen levels for the cupcakes baked with
sugar, Stevia, Sweet N’ Low, and Splenda, including a control. The highest mean was
the sugar cake with a mean of 156.360, and the lowest was the Sweet N’ Low cake with
a mean of -767.568. The lowest range was the Stevia cake with a range of 3.698; the
highest was the Sweet N’ Low cake with a range of 1482.073. The mode, however, was
not applicable. The Sweet N’ Low cake had the highest standard deviation out of the
other independent variables; the standard deviation of the Sweet N’ Low cakes was
1047.984. The Stevia cake had the lowest standard deviation which was 2.615. The
control oxygen levels started off lower than the other independent variables. The Splenda
cake dropped around hour 96 and the Sweet N’ Low cake dropped around hour 24. The
control had an increase at around 24 hours. The Sugar and Stevia cakes, however, stayed
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constant throughout the testing period. There was a statistically significant difference
(p>0.05) for change in oxygen levels between the container with no cake and the Splenda
cake, and no cake and the Stevia cake. However, there was no statistically significant
difference for change in the oxygen levels for the rest of the independent variables tested.
The data above failed to reject the null hypothesis that if the mini pound cake is made
with a sugar substitute then it will not take longer to decompose compared to the cake
made with refined sugar, and the data did not support the hypothesis.
Table 3: Mean of Temperature over 5 days Temperature (˚F)
Nothing Sugar Stevia Sweet N’ Low
Splenda
Day 1 60 62 63.5 61 60 Day 2 60.5 62 64 61.5 60 Day 3 59.5 62 64 61 59.5 Day 4 61 63.5 63.5 63 60.5 Day 5 60 63 63 62.5 63
Figure 3: Mean of Temperature vs. Time
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Table 3 and Figure 3 show the effect of the sugar and sugar substitutes on the
mean temperature levels of cupcakes. The highest mean was the Splenda cake at 0.6, and
the lowest mean was the Stevia cake at -0.1. The mode was not applicable. The highest
range was the Splenda cake at 1.2, and the lowest range was the control at 0. The
Splenda cake had the highest median at 0.6, and the control had the lowest median at 0.
The highest standard deviation was the Splenda cake at 0.848, and the lowest standard
deviation was the control at 0. The temperature was tested once every day at
approximately 1 o’clock pm. The container with no cake and the Splenda cake had the
same starting temperature. The Stevia and Splenda cakes had the same ending
temperature. The Sugar, Sweet N’ Low, the control, and Splenda cakes had a decrease
on day 3. The Splenda cake , however, continued increasing, unlike the other sugar
substitutes that went up at day 4 and back down on day 5. There was no statistically
significant difference for change in the temperature levels between any of the variables
tested.
VI. Conclusion
The purpose of this experiment is to determine the effect of Stevia, Sweet N’
Low, Splenda, and sugar on the shelf life of a cupcake. Major findings were that overall
there were no drastic drops in comparison to the entire experiment; however, for some
substitutes there were a lot of sporadic changes in both carbon dioxide and oxygen levels.
The temperature levels were approximately consistent because the location of the
cupcakes never changed. They were housed in a very controlled environment, as
compared to someone’s house. In a house there would many factors that could possibly
change the results, including temperature changes, sunlight exposure, and number of
people coming in contact with the cupcake. It was hypothesized that if the cupcake is
made with a sugar substitute then it will take longer to decompose compared to the cake
made with refined sugar. The data collected shows that the hypothesis was not supported.
The sugar has a lower decomposing rate, in comparison to the sugar substitutes. Previous
studies by Gelinas, Roy, and Guillet show that the synthetic cocoa stalled the
decomposition rate. Our data supports their findings. The hypothesis was chosen because
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it was thought that the synthetic substitutes would last longer because they are artificial.
The limitations for this study of shelf life were the technology issues, which prevented
the researchers from not having sufficient time for the proper amount of trials. From a
scientific standpoint, it would have been better to extend the trials so the mold collected
on the cupcakes could be tested as well. Also, there was not enough technology like the
ones found in food chemistry labs that adequately measure shelf life parameters. There
was only access to five Biochambers and five sensors of each type. For further studies, it
is recommended that the trials be extended and performed more times, so more
information and data could be collected. Also, the amount of microorganisms that grow
on each mini pound cake could be measured over time. Shelf life is a big determining
factor for big grocery store chains; this experiment could help these large companies
decide whether or not a cake could be safe for the customer to consume.
VII. Acknowledgements
We would like to thank Mr. Bill Cherry for helping us with all of our technology
problems; our parents, for providing transportation and support; Heathwood Hall
Episcopal School, for providing funds and a place to work; and last but not least, Mrs.
Lisa Norman, our honors biology teacher, without her support and patience, this project
wouldn’t have happened.
VIII. Works Cited
Dunn J. Way of Shelf Life. Food Manufacture 2010 May; 33-34. Graham, Ian. "Chapter 5: Packaging and Preserving." Food Technology.
London: Evans Brothers Limited, 2008. 48. Print. Kaplan, Aaron, and Leonora Reinhold. "CO2 CONCENTRATING
MECHANISMS IN PHOTOSYNTHETIC MICROORGANISMS." Annual Review of Plant Physiology and Plant Molecular Biology 50 (1999): 539-570. Print.
Kilcast, David, and Persis Subramaniam. The Stability and Shelf Life of Food. Abington, Cambridge: Woodhead Publishing Limited, 2010. Print.
Malovany D. Live Long-g-g and Prosper. Snack Food & Wholesale Bakery 2002 Mar.; 1-3.
Reid, Daniel. "Sugar." Which colon cleansing gives Best Results? The one where someone personally guides you! . HPS-Online, n.d. Web. 10 Oct. 2010. <http://www.hps-online.com/foodprof1.htm>.
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Sarquis E.D., Mickey. "Preservatives." Chemical Cuisine Spring 2001: 1. Print. Shultz, Martin. "Month-long bread? Getting the basic seven-day extended-shelf
life bread formula right is hard enough. Moving to 30 days can make any baker lie awake at night for a number of reasons. (Ingredient R&D)." Snack Food & Wholesale Bakery 1 May 2003. Print.
Taoukis, Petros, and Theodore Labuza. "Integrative Concepts." Food Chemistry Mar. 1996: 88. Print.
"Technical brief, measuring carbon monoxide." Western Area Power Administration. Energy Services, n.d. Web. 10 Oct. 2010. <http://www.wapa.gov/es/pubs Terao, Tomio, and Shu Miura. "Influence of free-air CO2 enrichment (FACE) on the eating quality of rice." Journal of the Science of Food and Agriculture 85.11 (2005): 1861–1868. Print Wilson L R. Easy Dessert With 5 Ingredients or Less. (TX): Cookbook Resources LLC.; 2003. 1 p.