Measuring Amounts of Vitamin C in Apple Juice

1. Measuring Amounts of Vitamin C in Apple Juice • Leah Bury, Grade 9

2. Using titration to find out which type of apple juice (from concentrate, not from concentrate) contains the most vitamin C.

3. Research Titration- method that uses a solution with a known concentration to find the concentration of a second solution

4. Hypothesis • If two different types of apple juice differ in ingredients and/or type, then they will have different amounts of Vitamin C.

5. Materials • Apple Juice (20 mL) • Apple Juice from Concentrate (20 mL) • Vitamin C Tablets (125 mg) • Distilled Water • Iodine Solution (50 mL) • Soluble Starch (.125 g)

6. Procedure • First, Iodine and distilled water were mixed to create a 25% Iodine solution. • A starch indicator solution was made by adding .125 g of starch to 25 mL of distilled water. • A vitamin C standard solution was made by mixing 125 mg of vitamin C with 50 mL of distilled water. • The standard vitamin C solution was titrated by adding 3 drops of the starch indicator and measuring the amount of Iodine solution needed to turn the vitamin C solution black. • Then 20 mL of apple juice was titrated. • After that, 40 mL of apple juice from concentrate was mixed with 40 mL of distilled water. • 20 mL was titrated.

7. Data Amt. of Vit. C

8. Conclusion • If two different types of apple juice differ in ingredients and/or type, then they will have different amounts of Vitamin C. • The hypothesis was supported: the 2 different types of apple juice contained different amounts of vitamin C. • The apple juice (not from concentrate) contained the most vitamin C. The vitamin C solution contained the least vitamin C.

9. Sources: • Dartmouth College. (n.d.). ChemLab: Titration. Retrieved from Dartmouth College website: http://www.dartmouth.edu/‌~chemlab/‌techniques/‌titration.html • Elsievier Inc. (2008). Vitamin C. In The Vitamins: Fundamental Aspects in Nutrition and Health (pp. 236-241). Burlington: Elsevier Academic Press. • Guch, I. (2006+). Chapter 23: Acids and Bases. In The Complete Idiot’s Guide to Chemistry (2nd ed., pp. 258-259). Marie Butler-Knight. • Helmenstine, A. M., Ph.D. (n.d.). Vitamin C Determination by Iodine Titration. Retrieved from About.com website: http://chemistry.about.com/‌od/‌demonstrationsexperiments/‌ss/‌vitctitration.htm • Olson, A. (2007, October 11). Which Orange Juice Has the Most Vitamin C? Retrieved from Science Buddies website: http://sciencebuddies.com/‌science-fair-projects/‌project_ideas/‌FoodSci_p009.shtml?fave=no&isb=cmlkOjQ1MzQzODcsc2lkOjAscDozLGlhOkZvb2RTY2k&from=TSW

10. Thanks!