Quantitative Analysis of Vitamin C Contained by Foods

1
Quantitative Analysis of Vitamin C Contained by
Foods
2
Vitamin C

• Vitamin C is also known as ascorbic acid. Its
  absence from our bodies results in deficiency
  disorders such as scurvy.

3
Ascorbic Acid

• Ascorbic acid is the active ingredient in fruits
  and vegetables that helps to prevent scurvy.

4
Ascorbic Acid

• Ascorbic acid is a powerful biological
  antioxidant.
• It helps to keep the iron in the enzyme, prolyl
  hydroxylase

5
Today we will

• Calculate the amount of vitamin C in our fruit
  drink.
• Titrate a fruit drink solution with Iodine.

6
The titration

• As we titrate our fruit drink solution with
  iodine, the vitamin C is oxidized by the iodine.
  When there is no more vitamin C to be oxidized,
  there will be an excess of iodine. This iodine
  will combine with the starch to make a blue
  solution.
• I2 starch ? iodine starch complex (blue)

7
Calculations

• To calculate the amount of vitamin C in your
  fruit drink you will use the amount of iodine
  titrated.
• 1 mL of I2 (0.01 M) 1.76 mg vitamin C

8
Safety Concerns Ascorbic acid

• Inhalation irritant
• Ingestion irritant, large oral doses may cause
  gastrointestinal disturbances
• Skin contact irritant
• Eye contact irritant
• Mutagen, tumorigen and reproductive effector

9
Safety Concerns Hydrochloric Acid

• Inhalation corrosive, coughing, choking,
  inflammation of the upper respiratory system,
  pulmonary edema, circulatory failure and death
• Ingestion corrosive, pain and burns of the
  mouth, throat, esophagus and gastrointestinal
  tract, nausea, vomiting, diarrhea and death
• Skin contact corrosive, redness, pain, burns,
  ulcers and discoloration of the skin
• Eye contact corrosive, burns and permanent eye
  damage
• Tumorigen, mutagen and reproductive effector

10
Safety Concerns Iodine Potassium Iodide

• Inhalation irritant,
• Ingestion irritant, nausea, vomiting and
  diarrhea
• Skin contact irritant, sensitization and
  allergic reaction
• Eye contact irritant
• Teratogen

11
Safety Concerns - Starch

• Inhalation coughing and sneezing
• Ingestion no known effects
• Skin contact no known effects
• Eye contact mechanical irritation