Effects 4Materials and Procedure Page 6Results Page 9Conclusion,

Effects of Time on Fructose Content in Bananas: To peel or not to peel?Chemistry Experimental Investigation ___________________________________________Signature of Sponsoring Teacher ___________________________________________Signature of School Science Fair Coordinator TeacherMora Vittum640 W. Scott St.Chicago, IL 60610Grade 7Table of ContentsTable of Contents Page 1Acknowledgments                                                                                       Page 2Purpose and Hypothesis                                                                             Page 3Background Research/Review of Literature                                                   Page 4Materials and Procedure                                                                              Page 6Results                                                                                                             Page 9Conclusion, Reflection, Application                                                           Page 13Reference List                                                                                              Page 16 AcknowledgmentsI would like to acknowledge and thank my parents for assisting in the buying and brainstorming parts of the experiment. My Dad was encouraging throughout the duration of the project, and my Mom was very helpful during the writing and recording process. Lastly, I would like to thank Mrs. Machado for being a continuous guide and helping hand for each and every student through the entirety of the project. Purpose and Hypothesis Purpose – The purpose of this experiment is to determine the effects of time on fructose content in bananas.Hypothesis – If the ripening period allowed for pears and bananas increases, then the fructose levels/dissolved sugar content will rise, because of the changes in composition (carbohydrates, hydrolase, kinase, amylase, etc.) of the fruit that take place as a result of hormone release ethylene when a banana ripens. Review of Literature Have you ever bitten into an unripe banana? Eaten a banana with a brown spot? Did you notice that a brown banana might be sweeter in flavor than a green banana? Do the chemical and color changing processes affect the fructose content in bananas? When bananas ripen, certain hormones create new features to the fruit. These processes may change the amount of fructose (fruit sugar) in the banana. This experiment was used to determine if this fructose changes as the ripening period increases. To do this, tools like a refractometer are used. These handheld devices are commonly used by farmers and home breweries. These two put together make this experiment possible.  Bananas ripen when enzymes released after the hormone ethylene is produced. Ethylene is given off by ripening fruit throughout the process. It also signals to other enzymes to be produced, “Release of ethylene gas triggers whole families of enzymes, including amylases, kinases, hydrolases and pectinases to work their magic and neutralize acids, form anthocyanins that give colors to fruit, and soften hard, inedible fruits into toothsome, delicious ones. One critical element of the ripening involves the conversion of starches to sugars.”(education.com, “”,) . This is why many people say to keep fruit in paper bags, so that this hormone is contained, which speeds up the ripening. Hormones like ethylene break down sugars and various other substances in order to create the common features of a fully ripened banana. This would explain the increas of fructose in the banana. One feature of a ripe banana that ethylene does not cause is the coloring (scienceline.ucsb.edu, “What causes Banana peels to turn brown?”). Due to the presence of chlorophyll in an unripe banana, the pigment of the popular fruit is green. Once ethylene is being heavily produced, amino acids are broken down in the banana, which replaces the green chlorophyll with the yellow coloring many consumers know well. Brown bananas are often called the result of “over enzymatic browning” similar to the processes many trees go through when their leaves change colors and fall when the weather gets cold, (scienceline.ucsb.edu, “What causes banana peels to turn brown?”, 2006). The sugar content of a banana can be measured with tools like a handheld refractometer. Hand held refractors have a variety of uses, both household and scientific. On the daylight plate of the tool, (place where the liquid is read) the sample is put through a series of lenses in which it then is read and displayed on the measuring scale. The scale can be seen and read through the eyepiece, when put up to a light source. The measurement read is out of degrees brix, “measurement of the dissolved sugar-to-water ratio of a liquid” (sciencebuddies.com). For example, if the scale reads 5, this means that there is 5 grams of sugar per 100 grams of “solution”(refractometer.pl, ” Handheld Refractometer”). Farmers often use refractometers to measure quality and ripeness of a fruit, “Juice factories and vineyards especially use refractometers so they can  measure the level of flavors in the juices and blend them to consistent brix level every time. Many companies are also now offering big bonuses to farmers who can produce high brix fruits because it means they have to add less artificial sweetener to the juices which are devoid of any nutritional value” (agriculturesolutions.com). These farmers use measurements from a refractometer to know when crops are ready to harvest, and make sure that the quality of the fruit is undeviating, (education.com).Materials and ProcedureMaterialsQuantity Collander2Refractometer (handheld)1Bananas (unripe)30Distilled Water3.8mlButter Knives (washed in between uses)5Cutting Boards2 (or more)Food Scale1Notebook/Computer (either, just to record data)N/AUsable source of waterN/ASmall glass containers2-5 (wash in between)Fork2+ (wash in between)Gloves1 Box of 100Knife1Dropper1 (minimum)ProcedurePurchase 30 unripe bananas, each with 5 in the bunch that have similar/the same coloring as the image shown before. (Akkoc, Telegraph, 2014)2) Put on the gloves, and switch gloves every banana trial3) Use 5 of the unripe bananas for the first trial. 3a. Peel the banana and cut a section out of it. 3b. Measure it out to 50 grams(If it weighs too much, remove some, too little, vice versa). To do this, use a food scale. 4) Mash the banana as best possible, and add 60 ml of distilled water to the mashed banana. 5)  Moisten the filter at the bottom of the espresso press. Change the filter after each test.    5a. Put this mixture into the espresso press, and push down with maximum pressure on the plunger to get the most liquid out as possible. 6) Then, calibrate the refractometer by taking a clean dropper, and covering the entirety of the daylight plate with the liquid. 6a. Through the eyepiece, check to make sure that the reading is at 0. 7) Then, use the dropper to drop enough to cover the entire Daylight Plate of the refractometer. 7a. Next, hold the daylight plate towards the light source, and then look through the eyepiece, and record the # of brix that the white line appears to stop at. If the line does not fall on/near a benchmark, round down 8) Using the directions of placement on the refractometer, apply the liquid to the sample part of the handheld device. 8a. Read the result that the device provides, and record this for 0 days. 8b. Record this in a table on a notebook or computer.9) Do these steps for 5 bananas on the day of purchase. 9a. Everyday after the day of purchase (day 1, day 2, day 3, day 4, day 5), follow steps 2-8a for 5 more bananas, in total, adding up to 30 bananas.ResultsIndependent: Days of ripening allowedDependent: Fructose contentDay of Purchase: 7:45pm 11/10Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 103°50 gramsBanana 204°50 gramsBanana 304°50 gramsBanana 403°50 gramsBanana 503°50 grams1 day of ripening allowed: 7:18pm 11/11 (rounded down)Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 604°50 gramsBanana 7010°50 gramsBanana 805°50 gramsBanana 906°50 gramsBanana 1006°50 grams2 Days of Ripening allowed: 7:20 11/12 Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 11011°50 gramsBanana 1207°50 gramsBanana 1308°50 gramsBanana 1408°50 gramsBanana 1508°50 grams3 Days of Ripening: 6:06 11/13Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 1609°50 gramsBanana 17011°50 gramsBanana 1809°50 gramsBanana 19010°50 gramsBanana 20010°50 grams4 Days of Ripening: 7:06 11/14Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 2109°50 gramsBanana 22014°50 gramsBanana 23012°50 gramsBanana 24014°50 gramsBanana 25013°50 grams5 Days of Ripening: 6:34 11/15Fruit TypeDays of RipeningDegrees (°) BrixAmount of Fruit MeasuredBanana 2601350 gramsBanana 2701450 gramsBanana 2801650 gramsBanana 2901350 gramsBanana 3001550 gramsNotes & ObservationsDay of purchase, Banana split into sections fairly easilyDid not peel easilyDay 2: Peel came off easier Was easier to mashDid not get as much liquid in Banana 7 as Banana 6Banana 8 also was not letting as much liquid outBanana 9 had one small brown spotDay 2: Bananas were the similar coloring to Day 1, being the same amount “mashable”Additional photos were taken, but I did not upload them yetVisible Bruising on Banana 11 both inside and outData seems to be increasing at an almost linear rateDay 4: Easy to mash (not easier, compared to Day 3) mealy, Brown spotting all over. Day 5: Visible brown spotting on bananas 26-30 Days of RipeningDegrees (°) Brix BANANA (AVERAGE) 03.4°16.2°28.4°39.8°412.4°514.2°Graph The green dots on the graph are the averages from the table below. The blue line is a model equation that best fits the average values (desmos.com)This equation is:  y = 2.3x+3.4Y – the y in the equation represents the average value the model predicts2.3 – the 2.3 represents the average increase in fructose every day the X – amount of days banana has been ripened for since day of purchase (0)3.4- The y intercept, or the value recorded on the day of purchaseCorrelation coefficient: .9969 (socscitatistics.com, 2017) The data in tables above all show incremental increases in dissolved sugar content from a day to day basis.Conclusion:The objective of this experiment was to determine if ripening of a banana increases that total fructose content. The proposed hypothesis was that if the ripening period allowed for pears and bananas increases, then the fructose levels/dissolved sugar content will rise, because of the changes in composition (carbohydrates, hydrolase, etc.) of the fruit that take place as a result of hormone release (ethylene). The proposed hypothesis was correct, as the graph and data marked is showing a positive, closely linear relationship. The correlation coefficient is .9969, which means that the data is .0031 from being exactly linear, as shown in the graph. This correlation coefficient represents the variability of the values on the graph. Not only do the results provide a clear positive relationship, but the results also show a clear linear relationship, which was not expected or predicted in the hypothesis. During and after the experiment, a variety of math skills were utilized. These skills were good to practice outside of the classroom, and useful in interpreting the data. For example, the use of statistics in the form of calculating the correlation coefficient, to better describe the spread of data. Throughout the duration of the experiment, knowledge was gained, and results became clear.Reflection:If I were to do this experiment again, I would change numerous things. Next time, I would want to test if these conclusions are true for most fruits? How does this vary with fleshy vs other types of fruit? How do these results differ for organic vs. non organic fruits? Applying these ideas to my experiment would make the results and conclusions more accurate. Potential experimental errors are likely to happen, and come in a variety of forms. Some are predictable and preventable, but many are not. The possible mechanical errors additional liquid measured on the daylight plate, other than the banana “juice”. Contamination between bananas, likely as a result of not fully washed materials. Another possible error would be human, which includes wrong measurements (of banana, water, and dropper), inaccurate reading of the refractometer, washing the cutting board so nothing that was there before is tested. If I were to do this experiment again, I would add elements to make sure the results were accurate, and I had a variety of data to draw conclusions from. For example,  using a refractometer that is used strictly for the purposes of sugar content measurements. Also, testing multiple types of fruit, so that if one did not increase, it would be a wider variety of fruit to make conclusions about. In addition, I would test through a larger period of time, so that when the coloring of the banana is no longer yellow, I would have more data to conclude from. The reliability of the conclusions based on the given results proves to show that the results were accurate, with the circumstances given. All in all, my experiment could have had some improvements, but was very accurate.Application:This experiment can be applied to many categories of science and real life scenarios. Food science, discoveries in food science and the biology of how a fruit ripens, and the result in has on taste and sugar content all apply to this experiment. Many consumers who are looking to diets – when looking to avoid sugars or fructose, which banana is better to eat? When consumers are cooking with specifc ripeness of fruits (banana bread, apples, etc…) is that because these bananas have more fructose?  The result of this experiment is important in science, as it provides an insight into what goes on in the fruit when it ripens, and the effects on the sugar inside, that we cannot see. The demand of unripe bananas comes from the consumers, who know how a banana ripens and the time it takes to. When people buy bananas green, and decide to not eat them until they SEE a certain color, is it because the bananas are more sugary? Or does the content stay the same, and the flavor just evolves as time goes on? This experiment can help to explain this, and give consumers another way to identify ripeness in a banana.Reference ListAkkoc, R. (2014, July 15). Eat unripe bananas but don’t eat mash or cook with olive oil for a     healthy diet. Retrieved November 19, 2017, from http://www.telegraph.co.uk/news/health/news/10968618/Eat-unripe-bananas-but-dont-eat-mash-or-cook-with-olive-oil-for-a-healthy-diet.html(n.d.). Retrieved November 19, 2017, from http://plantsinaction.science.uq.edu.au/book/export/html/84(n.d.). Retrieved November 19, 2017, from https://www.desmos.com/calculatorFACLM, M. G. (n.d.). If Fructose is Bad, What About Fruit? Retrieved November 19, 2017, from https://nutritionfacts.org/video/if-fructose-is-bad-what-about-fruit/From Bitter to Sweet: How Sugar Content Changes in Ripening Fruit. (n.d.). Retrieved November 19, 2017, from https://www.sciencebuddies.org/science-fair-projects/project-ideas/FoodSci_p063/cooking-food-science/how-sugar-content-changes-in-ripening-fruit#backgroundFruit Ripening. (n.d.). Retrieved November 19, 2017, from http://plantphys.info/plants_human/fruitgrowripe.shtmlE. (2013, June 14). Measuring Sugar in Fruit Using a Refractometer | Science Project. Retrieved November 19, 2017, from https://www.education.com/science-fair/article/measure-sugar-ripe-fruit/Hogeback, J. (n.d.). Why Do Bananas Turn Brown? Retrieved November 10, 2017, from https://www.britannica.com/demystified/why-do-bananas-turn-brownRefractometers (A.K.A Brix Meter). (2017, November 20). Retrieved November 20, 2017, from https://www.agriculturesolutions.com/products/crop-soil-and-water-testing/refractometers-brix-metersS.L., B. (n.d.). Types of fruits. Retrieved November 19, 2017, from http://www.botanical-online.com/frutoscarnososangles.htmSocial Science Statistics. (n.d.). Retrieved November 19, 2017, from http://www.socscistatistics.com/What causes Banana peels to turn brown? (n.d.). Retrieved November 19, 2017, from http://scienceline.ucsb.edu/getkey.php?key=1213