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Does Pectinase Act On The Apple To Produce More Juice?

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Biology Coursework Does Pectinase Act On The Apple To Produce More Juice? Background Knowledge An enzyme is a protein molecule that speeds up chemical reactions. Each enzyme has a unique shape that determines its function. One enzyme works on one type of substrate. Enzymes break down large molecules into smaller more manageable molecules, and they can be used more than once. Enzymes work best at their optimum temperature, which is around 40?. When an enzyme is in a hot temperature or a high pH the enzyme denatures, which means it effectively dies. Prediction/Hypothesis There will be more juice produced from the apple when pectinase is added than when just water is added. Reasons for making my prediction The pectinase will act on the pectin in the apple and break it down into small molecules. Controlling Variables * Temperature * Volume of substances used Why do I need to control these? ...read more.


I will also wear a lab coat to protect my skin and clothes from any chemicals. I will move any obstructing and unnecessary objects to prevent any accidents, like tripping over a bag. Method I first place a piece of apple on a white tile. Then I cut it into small chunks. Next I put these chunks into a blender, which will produce a soluble mash. I then add 5 grams of the mashed up apple into a test tube. Then the one test tube I add 2cm� of pectinase. Then into a second test tube I add 5 grams of the mashed up apple and with it I put 2cm� of water. I next place the test tubes into a hot water bath for ten minutes. After ten minutes I remove the test tubes from the hot water bath and empty the contents into two separate measuring cylinders with funnels and filter paper on top. ...read more.


This prediction was correct because pectinase is an enzyme used to make fruit juices. The pectinase acts on the pectin in the apple, which holds the cell walls of the fruit together, and they begin to deteriorate which produces the juice. Evaluation Problems with equipment: I was unable to use a proper hot water bath so instead I had to use a beaker and keep refilling the beaker with hot water so it was a steady 40?. This meant that it wasn't constantly at the correct temperature. Possible Inaccuracies: The fact that I didn't have access to a hot water bath meant that the temperature of the water would have been inaccurate at times. Anomalous Results: I did not have any anomalous results. Improvements: I could do the experiment again and collect more results. I could record the amount of juice every minute rather than every 10 minutes. This way I could have a more accurate understanding of the result of my experiment. If I did the experiment again I could use a hot water bath, that way my results would be a lot more accurate. Natasha Rayden ...read more.

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