PROPOSAL | Snapcracklepop

INTRODUCTION

Rice Krispies cereal is known for their slogan “Snap, Crackle, and Pop”, referring to the fun sound that the cereal makes when you pour milk into your bowl and start off the day with a hearty breakfast. This particular cereal may own this slogan, but is it the only one that truly snaps, crackles, and pops? How is the sound produced by the classic breakfast choice of milk and cereal affected by the type of cereal and the type of milk being used? In order to solve this tasty mystery, this experiment will take on the challenge of measuring the sound pressure produced by various cereals when coming in contact with different kinds of milk.

Figure 1: Materials involved in the screening experiment consisting of the three tested cereals, Vernier LabQuest, and 2% milk.

PROBLEM AND HYPOTHESIS

Mornings are hard. Who couldn’t use a little “snap crackle pop” as the sun breaks through the kitchen blinds? Our team is invested in determining the cereal with the loudest sound to bring the general public the most fun to begin the day. We’ve all heard the gentle crackling of America’s favorite breakfast, but now we are quantifying the beloved sound to determine the type of cereal, ratio of cereal to milk, and type of milk that produces the greatest sound level in the initial 15 seconds as well as a sustained sound level within 90 seconds.

We will compare the sound level,in decibels, of Rice Krispies, Cheerios, and Cookie Crisps with constant volumes of cereal and milk using a sound-measuring phone app called Decibel X, allowing us to analyze the decibels produced within the initial 15 seconds and the sustained sound level within 90 seconds. We will also focus on the sound of the cereals in different amounts of milk and then in 2% milk and almond milk, using the same decibel app.

Hypothesis: We hypothesize that the type of cereal, the type of milk, and the amount of milk added to a cup of cereal will affect the intensity of sound produced and the amount of time the bowl of cereal will crackle. We expect the airiest, least dense cereal, the least fatty milk, and the greatest volume of milk to produce more decibels foe the most amount of time. Therefore, our prediction is that the bowl of a cup of Rice Krispies with ¾ cup of 2% milk will produce the greatest sound for the longest time interval.

DESIGN OF EXPERIMENT

Figure 2: Block diagram to organize the design of experiment.

The block diagram shown in Figure 2 provides organization to the design of experiment. It consists of controllable input factors, the experimental process, response variables, uncontrollable input factors, and statistical process control. This system identifies the components of our experiment that we control and then how the process of the experiment will yield factors that we optimize using statistical process control.

EXPERIMENTAL PLANNING OF DOE

Based on our three controllable factors, cereal, milk, and amount of milk, we decided on 2 to 3 levels of variation to experiment on the sound level and how long the audible sound is produced. These controllable factors are the basis of our experiment and trials will be run to test the significance of each variable.

Figure 3: Controllable factors listed with their respective levels

Equation 1: We can conclude that 12 unique trials will be run from the above equation.

Our team determined that 12 unique runs would be run to account for the three levels of cereal, two levels of milk, and two levels of milk volume. Each run will be replicated 3 times for greater statistical significance, totaling to (12 runs)*(3 trials)=36 trials. We will also include 2 baseline tests per trial to ensure consistency from the beginning to the end of the experiment, totaling to 38 trials as shown in Table 3 below.

Table 1: Experimental plan with controllable factors and levels.

We expect interactions to play a significant role in the results of our tests. We predict that the type of cereal will affect the level of sound produced; Rice Krispies will be the loudest while Cookie Crisps will be the quietest. Rice Krispies are filled with air pockets, much more so than other cereals, so when milk is added, there will be more walls to break and create sound. 2% fat dairy milk will likely create more sound than almond milk because it contains less fat and can theoretically break through air pockets in the cereal easily. We also expect that the amount of milk added to a cup of cereal will impact the length of time that the cereal crackles; more milk will result in a greater crackling time because there will be more liquid for the cereal to absorb.

PRACTICAL CONSIDERATIONS

In our screening experiment, we tested three different cereals which were Rice Krispies, Froot Loops, and Cinnamon Frosted Flakes. Each container was filled with one cup of a particular type of cereal then filled with a half cup of 2% milk. With one type of cereal at a time and directly after the milk was poured, the sound pressure was recorded using a Vernier microphone and LabQuest device for 60 seconds. The materials used in this experiment are shown in Figure 1. This was done for each type of cereal and the results stated that the Rice Krispies produced an average sound pressure of .0517 mPa which was higher than the average sound pressures of .0240 mPa and 0.0106 mPa with Froot Loops and Cinnamon Frosted Flakes, respectively. We came to the conclusion that some changes will need to occur from our screening experiment to our actual experiment, such as the three types of cereal which will be Rice Krispies, Cheerios, and Cookie Crisps, and also how we measure the sound. Instead of using the LabQuest and Vernier microphone (as seen being used in Figure 4), we will use the more cost-effective and time-effective method of using a decibel-recording phone app called Decibel X. Also, instead of measuring sound pressure which proved inconvenient alongside the LabQuest, the sound level in decibels will be measured using Decibel X.

Figure 4: Method of testing during the screening experiment in which the Vernier microphone and LabQuest devices were used to measure sound pressure.

(mPa)

Figure 5: Graph of sound pressure vs. time resulting from screening experiment.

In Figure 5 above, the three different cereals used in the screening experiment (Rice Krispies, Froot Loops, and Cinnamon Frosted Flakes) were in milk and the sound pressure was measured over a period of 60 seconds. The area under the curve (integral) of each cereal type was recorded by the LabQuest to determine the average sound pressure over the entire 60 seconds. These results were stated in the previous paragraph.

Figure 6 below displays the data collected from a test run of the DecibelX, a noise meter app installed on Meghan's iPhone. The data represents the loudness of a face-to-face conversation collected in the app. The data can be exported as a .CSV file to be analyzed in Microsoft Excel.

Figure 6: Graph of sound level data collected over time by the DecibelX app on the iTunes store.

Equipment Feasibility: The only tools and sensors that our experiment required was the decibel-recording phone app known as Decibel X for data collection which was free to download from the App Store. As far as equipment, we will need at least three containers for the cereals, the three types of cereal we will officially be testing (Rice Krispies, Cheerios, and Cookie Crisps), 2% milk and almond milk, and a measuring cup. The containers and measuring cup will be provided by one of the team members, whereas the milk and cereal will be bought from a store. One last thing that will be needed to meet the proper conditions for our experiment would be a quiet/sound-controlled room with a table or desk such as a study room. This will help block any ambient noise disrupting the results of our data.

Table 2: Documentation of experimental costs

Time Feasibility: Each run of our experiment will take approximately 3 minutes. This includes 1 minute to measure out the cereal and the milk then pouring the milk, then 1-2 minutes for data collection of the sound level until it drops below the specified decibel value. Time of whole experiment = 3 min. * 42 runs = 2 hours and 6 minutes.

Expertise Feasibility: The members of our group are proficient in conducting the necessary procedure and operating the equipment for data collection. This is mostly due to the experience we have obtained through the screening experiment.

Personnel Management: One of our members is primarily responsible for the website design and is also the equipment conductor for the experiment. The other is responsible for the data collection as well as the overall task manager to ensure that all tasks are completed on time. The deliverables are then evenly split between the two members of the team.

Potential for Benefit: Our team suspects to gain extensive knowledge of which kind of cereal with which kind of milk produces the highest and longest sound level. One may use this information to determine the effects that are compromised when given a “louder” cereal, such as how the “louder” cereal affects sogginess. This experiment also narrows the uncertainties surrounding the goal of an optimal breakfast. In other words, we want to help make breakfast more fun!

BRIEF TRADITIONAL EXPERIMENT

We propose a traditional experiment varying the volume of cow 2% fat milk added to 1 cup of cereal and measuring the resulting sound level. We will record decibel data (y axis) for ten trials of increasing the volume of milk by 1/8 cup each time. Our predicted results are illustrated in Figure 8 below.

ANTICIPATED RESULTS

Figure 6: The effect that type of cereal, type of milk, and volume of milk has on the sound level.

Figure 7: The effect that type of cereal, type of milk, and volume of milk has on the length of time the sound level stays above the specified decibel value.

The DOE means plots (Figure 6 and Figure 7) represent the average sound level produced by each of the controllable factors in decibels and the average time for the cereal to become inaudible under various controllable conditions. We anticipate that the Rice Krispies will have the greatest average sound level while the sound level of Cheerios and Cookie Crisps will decrease respectively. We also expect that 2% milk will have a greater sound level than almond milk and ¾ cup of milk will have more decibels than ½ cup of milk added. In terms of time, we anticipate that Rice Krispies will produce sound for the most amount of time, followed by Cheerios and Cookie Crisps. We can also expect that almond milk and ¾ cup of milk will also maintain an audible sound for more time.

Figure 8: Vary x measure y experiment depicting the anticipated sound levels as volume of milk added increases.

We expect that varying the volume of milk added to a cup of cereal will affect the sound level. Based on previous knowledge, we can predict as the volume of milk added (cups) increases, the sound level (decibels) of the bowl of cereal will increase as shown in Figure 8. In theory, a greater amount of liquid saturating the initially dry cereal will infiltrate air pockets faster and create more sound at once. By varying the cups of milk added to the bowl of cereal, we will document and compare the resultant sound, the y-variable, with each input volume x-variable.

POINTS FOR FURTHER STUDY

Anticipated Challenges:

We may not be able to control all ambient sound interfering with the cereal readings on the decibel-recording app. We can lessen the effect of surrounding noises by conducting the experiment within a sound-controlled area such as a study room.
Consistency in mixing the ingredients, namely the milk distribution when pouring it onto the cereal, will likely be a challenge. In order to combat this potential problem that could possibly affect our results, we could develop a pattern system of pouring (such as an inward spiral motion) to evenly distribute the milk and also have the same person doing it for all trials.
Sustaining the quality of the perishable items involved in our experiment may pose to be a challenge (as well as controlling the urge to eat our ingredients). We want the cereal and milk to be as fresh as possible to maximize the accuracy of our results, so we should buy the materials needed as close to the conduction of the experiment as possible.

Possible Extensions to the Experiment:

Testing more cereals would be interesting for further study. There are many kinds of cereals with various shapes and densities that could provide a wider range of sound level values.
Our study could also benefit from testing how the sound level is affected by how much milk the cereal can hold. Future tests could measure the sogginess or milk retention of the cereal after the primary experiment by straining out the excess milk then weighing the saturated cereal.
Another extension of our study could explore the connection between the sound of cereals and its perceived taste. Past studies have found connections between favored champagnes and its fizziness, so similar connections may be found in the sound of cereal resulting from texture and favorite breakfast cereals.