Blog Fourteen

The final thing that I did for my SRP, is upload 3 videos of me performing trials 4 and 5, onto a USB. I tried endlessly in uploading the videos onto my blog, but they wouldn't work. You cannot rely on technology sometimes.

Blog Thirteen

Today, I completed my ‘Discussion’, ‘Conclusion’ and ‘Bibliography’. This was a difficult task to accomplish because I needed to have a logical understanding of different scientific principles involved in my experiment, and then explain why my results occurred the way they did, using these scientific principles. I also went through my entire SRP to proof read it and make any final modifications and correction of errors. I found that I needed to change my Risk Assessment slightly because I didn’t use a kettle in my experiment, and I had this resource put down as a potential hazard. Not to mention, when writing my discussion, I constantly referred to my original hypothesis, presuming that the more cocoa butter in a chocolate, the faster the melting speed. My modified hypothesis was that the amount of cocoa butter affects the melting speed of chocolate; however, I found differing results which are displayed in my discussion and conclusion. I spent a total of 4-5 hours completing the remainder of my SRP, and ensuring that all sections were as sophisticated as possible and met my marking criteria closely. Below is the work that I completed including my modified risk assessment.

 Discussion

Chocolate is a sweet confectionery made from cacao beans. These are seeds that originate from the cacao plant. They are found grouped in several large pods, and are harvested once ripe. The beans have a bitter sensation, which is generally weakened through a fermentation process to allow for the proper roasting and hulling of the beans, which give it their flavour. The beans then move onto being grounded into a chocolate liquor substance and hardened to form the solid chocolate that is renowned today, made up of cocoa solids and particularly cocoa butter, believed to make chocolate melt. To be more specific, cocoa butter is a highly stable polymorphic fat of the cocoa bean, melting at 36 Degrees Celsius. The butter comprises of different types of unhealthy fats such as palmitic, stearic and oleic acids, that remain consistently solid at room temperature, as opposed to healthier fats that are liquid at room temperature. When it is exposed to heat, it changes into a fluid state because it is made up of six different crystal forms, subsequently meaning that the arranged atoms within the chocolate are constant but positioned differently. The scientific principle of Polymorphism becomes cleverly introduced. Polymorphism is “the condition of occurring in several different forms.”   (Wikimedia Foundation, Incorporation. 2014, Polymorphism (Biology). Retrieved: April 28, 2014, from http://en.wikipedia.org/wiki/Polymorphism_(biology)). In this experiment, the cocoa butter and the chocolate appear to be solid at first, and eventually turn into a liquid from the heat generated by the stove. This heat forces the particles within the confectionery to move apart and vibrate as they gain more thermal energy and obtain a runny texture.

In this experiment, it was seen that, the white chocolate took the longest time to melt, on average 3 minutes across all 5 trials, while the dark chocolate took the quickest time to melt, on average 1min 40sec, and the milk chocolate was second fastest, melting in 2min 20sec, on average for all 5 trials combined, according to my graph. The results obtained in this experiment clearly identify a trend and relationship between chocolate and cocoa butter; the chocolate with the most amount of cocoa butter content took the longest time to melt, whilst the fewer cocoa butter content present within the chocolate resulted in a much faster melting speed. However, I originally hypothesised that the amount of cocoa butter will affect the melting speed of different types of chocolate. Therefore, I was expecting that the white chocolate containing 34.8% cocoa butter to melt the quickest, whilst both the dark and milk chocolates contained 29.6% cocoa butter. Yet, the opposite happened, meaning that my hypothesis was not entirely correct. Considering that the milk and white chocolates had the same cocoa butter quantity, the expectation was that they would take the same time to melt. However, according to the table of ‘Cocoa Butter Polymorphs’, dark chocolate took the quickest time to melt, because not only is it the most glossiest of all chocolates, but it’s melting point is 33.8 Degrees Celsius (Form V), as opposed to Form IV, belonging the milk chocolate, as it was kept in room temperature throughout the entire experiment. Despite this same principle applying for the dark chocolate, the dark chocolate possessed higher qualities of Form V, leading to its subsequent classification. The known melting temperature of chocolate/cocoa butter, generally speaking is 36 Degrees Celsius, and in the experiment, the three different types of chocolates were exposed to a heat of 100 Degrees Celsius (boiling temperature of water). Additionally, the dark chocolate would have clearly melted the quickest already having the highest melting point.

Of all the three types of chocolates, Cadbury’s dark chocolate is the healthiest, containing less milk, sugar and other elements, which all have different melting points. An increase of the addition of these ingredients, purposely affects the entire melting process, and speed of the chocolate, becoming more heat sensitive as it interferes with the cocoa butter. The additional fats therefore significantly reduced the white chocolate’s melting point, taking it longer for the Beta Crystals to loosen and turn into a fluid state of matter.

 Chocolate and Structure 2012. Retrieved: April 28, 2014, from http://www.nuffieldfoundation.org/practical-chemistry/chocolate-and-structure

Whilst performing the experiment, I accidentally ate some chocolate that I was going to use for my second trial. Waiting for the water to boil, I didn’t realise that the chocolate that I had put to the side of my kitchen bench had been weighed and was ready to melt. As a result, I had to re-weigh my dark chocolate, to make sure that I was using the same intended amount (24g). This could have been minimised if the chocolate was put in a separate container or already in the bowl, so that it was evident, that it had to be melted and used for the experiment. I also found that when I cut an entire row of chocolate for my first experiment, the weight was 24g, rather than 25g, stating at the back of Cadbury’s nutrition panels. Therefore, I had to use this measurement for all of my trials, if I wanted the experiment to be as consistent and as accurate as possible. I found myself, having to either add or take away chocolate to the serving size that had already been sliced for the experiment. To ensure that the weight was exact for each time I measured the recording (weight), a more accurate and precise or sophisticated cutting instrument/tool should have been used.          

Conclusion

The amount of cocoa butter does not affect the melting speeds of different types of chocolates. Originally through research it was believed that cocoa butter did affect a chocolate’s melting speed, because it was the ingredient that contained special polymorphic properties, making the chocolate less resistant to heat and causing Beta Crystal to separate more. However, this is only so, if the cocoa butter does not interact with other elements and ingredients found within the chocolate. For example, due to white chocolate’s excess milk and sugar content, the melting speed of the chocolate is decreased as all of the elements have different melting points, and interact with the cocoa butter, making it resistant to heat. Therefore, the melting speed of chocolate is affected by the quantities and types of ingredients comprised within a chocolate, not necessarily the cocoa butter itself.  

Bibliography

Research

Text

Films, TV, Video and Audio

Science: An Easier Way to Temper Chocolate (FLV Picture), 2013, America’s Test Kitchen., America. Producer America’s Test Kitchen. http://www.youtube.com/watch?v=p5_kheJtQO4

World Wide Page

Deakin University Australia. 2013,Chocolate. Retrieved: March 1, 2013, from http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Chocolate

Gordon, C. 2014, The Chocolate Life. Retrieved: March 1, 2014, from http://www.thechocolatelife.com/profile/LB

Sefcik, L. 2014, How does Chocolate Melt?. Retrieved: March 1, 2014, from http://www.ehow.com/how-does_5006509_chocolate-melt.html\
Thomson, W. 2014, How Does the Type of Chocolate Affect the Melting Time?. Retrieved: March 1, 2014, from  http://www.ehow.com/info_8319971_type-chocolate-affect-melting-time.html

World Wide Web (No Date)

RSC, (n.d.). Retrieved: March 1, 2014, from http://www.rsc.org/Education/Teachers/Resources/Inspirational/resources/4.1.4.pdf

Email

Todorovski, A. (todorovskiannalise@gmail.com), February 18, 2014. Student Research Project. (www.cadbury.com.au)

Images

World Wide Web
Mondelez International Group. 2014, Cadbury Dream Ingredients. Retrieved: February 17, 2014, from https://www.cadbury.com.au/Products/Blocks-of-Chocolate/Cadbury-Dream-Block/Cadbury-Dream-Ingredients.aspx
Mondelez International Group. 2014, Cadbury Milk Chocolate Ingredients. Retrieved: February 17, 2014, from https://www.cadbury.com.au/Products/Blocks-of-Chocolate/Cadbury-Milk-Chocolate-Block/Cadbury-Milk-Chocolate-Ingredients.aspx
Mondelez International Group. 2014, Cadbury Old Gold Original Ingredients. Retrieved: February 17, 2014, from https://www.cadbury.com.au/Products/Old-Gold-Blocks/Cadbury-Old-Gold-Original-Block/Ingredients.aspx

Discussion

Text

World Wide Web Page

Conjecture Corporation. 2014, What is Chocolate?. Retrieved: April 28, 2014, from http://www.wisegeek.com/what-is-chocolate.htm

Fairfield, J. 2012, The Polymorphism of Chocolate. Retrieved: April 28, 2014, from http://letstalkaboutscience.wordpress.com/2012/02/14/the-polymorphism-of-chocolate/

Wikimedia Foundation, Incorporation. 2014, Polymorphism (Biology). Retrieved: April 28, 2014, from http://en.wikipedia.org/wiki/Polymorphism_(biology)

Yoquinto, L. 2012, The Truth About Coca Butter. Retrieved: April 28, 2014, from http://www.livescience.com/36626-cocoa-butter-chocolate-lotion-benefits.html

World Wide Web Page (No Author)

Which Chocolate Melts The Fastest And Why? Dark, Milk or White Chocolate? 2013. Retrieved: April 28, 2014, from http://workathomemums.hubpages.com/hub/Which-Chocolate-Melts-The-Fastest-Dark-Milk-or-White

Image

World Wide Web Page (No Author)

Chocolate and Structure 2012. Retrieved: April 28, 2014, from http://www.nuffieldfoundation.org/practical-chemistry/chocolate-and-structure   

Blog Twelve

have now finished my entire results section of my SRP, and have started putting together my final report, with the assistance of my marking criteria. This took quite some time and a lot of effort, and hope that I have completed all of the sections correctly. I have taken a photo of the rough sketch of my graph and have constructed my two tables and graph and have arranged the written results of my experiment, outlining what observed during the experiment.

Blog Eleven

At the moment, I have only just touched on my results section slightly. I have an idea as to how to construct my tables according to my marking criteria. Constructing the tables was a difficult task however because I didn’t know how to label my headings and put all of the relevant data into a table. I have one table as the average melting speeds of all chocolates combined and one table for the melting speeds of the different types of chocolates in each trial. I am now working towards completing my graphs and hopefully my entire results section of the SRP.

Blog Ten

Today, I completed three more trials. This time however, my fourth and fifth trials have been recorded. I was slightly nervous whilst being recorded not wanting to forget my procedure or incorrectly talk my way through the experiment. From what I have observed and completed so far, I have found that the results for each trial are very similar with dark chocolate taking the quickest time to melt and white chocolate taking the longest time to melt. This means that my findings do to match my hypothesis because I have hypothesised that the chocolate with the most amount of Cocoa Butter will melt the quickest. My research showed me that white chocolate took the longest to melt rather than the quickest. Below are my videos and images.

 

 

Blog Nine

Also today, after I modified my experimental report, I conducted two trials. I followed my method step by step and I had my Mother take photos during the process, while I was conducting the experiment. The task was quite reasonable, not taking much time to complete. Tomorrow I hope to conduct my other three trials and record at least two trails to put in my blog. Below are my observations and proof of conducting the experiment. I also found that that of the two trials, Dark chocolate has taken the quickest to melt, with White chocolate taking the longest. Each type of chocolate takes about the same time to melt in each trial. However, I have used the snipping tool to upload the photos onto my blog because uploading and labelling each photo individually is be extremely time consuming. I tried to make my pictures and labelling as clear and as neat as possible.   

Blog Eight

Today, I made modifications to my experimental report. I wanted to do so before I actually conducted my trials. Reflecting on the feedback of my draft experimental design, I had been recommended to change my hypothesis, add a few more details to my method and make my variables more precisely controlled. I read through my SRP Booklet carefully and this assisted me with making changes to my report, giving me examples of experimental designs. Having changed my procedure meant that I had to include or take away certain equipment. I have recorded my changes below.

Hypothesis: The quantity (amount) of Cocoa Butter present within the Chocolate, will affect the chocolate’s melting speed.

Variables
Independent Variable: My Independent Variable is the type of chocolate that I will be using; milk, dark and white.
Dependant Variable: My Dependant Variable is measuring how long it takes for each different type of chocolate to melt completely.
Controlled Variable: My Controlled Variables include the brand of Chocolate that is being used (Cadbury), the serving size of the chocolate; 25g per square, the amount of chocolate being used for each trial, and the temperature of the water used in melting the chocolate (boiling point 100°C).

 Equipment List:

·         Regular Sauce Pan                                           

·         Regular Stainless Steel Bowl

·         Cadbury 25g White, Milk, Dark Chocolate Blocks

·         Stopwatch with 0.1 Second Accuracy

·         500mL Cold Tap Water per trial

·         Measuring Cylinder 500mL

·         Digital Scale

·         Regular Kitchen Knife

·         Wooden Chopping Board

·         Metal Spoon

 Experimental Procedure (Method)

1)     Fill up a measuring cylinder with 500mL of cold tap water.

2)     Pour this water, into a regular saucepan and place it over the stove at a medium heat.  

3)    Whilst the water is heating, cut a row of chocolate from the three Cadbury blocks using a kitchen knife and a wooden chopping board. This should be 4 squares with 25g/square (according to the nutrition panels).

4)     To ensure accuracy and consistency, place one of the broken rows of chocolate on a digital scale, using ‘Grams’ as the unit of measurement. The measurement that is recorded will be the initial weight used for all trails.   

5)     Once the water has boiled, you will know when it has started boiling because bubbles will slowly rise to the surface of the water; place one of the chocolate types into a regular stainless steel bowl.     

6)      Then, have this put on top of the saucepan filled with the boiling water.

7)     With the timer, start timing how long it takes for the chocolate to melt completely once the bowl is placed in the saucepan. Make sure to keep the stove running on the medium heat.

8)     Every 10 seconds, lightly press down on the chocolate 5 times using your metal spoon. Do this until the chocolate has melted entirely. If the chocolate is left as is, it will take extremely long for the particles to physically separate. Putting slight pressure on the chocolate with the spoon will visibly show you that the chocolate begins to melt automatically, once placed over the heat.  

9)    Record the result of how long it takes for all of the chocolate to melt, and stop timing when the chocolate has completely melted.

10) Repeat this for the other two different types of chocolates, within the trail; however keep the water boiling, as you rinse your bowl and wash your spoon.

11) When, you have completed one trail, repeat the same process, changing the boiling water which would be close to evaporation, at the start of each trail

12)  Also, remember to have at least 5 trials for each chocolate.