How can Preparation of Fruit and Vegetables effect Nutrient Levels? (Types…
How can Preparation of Fruit and Vegetables effect Nutrient Levels?
Types of Preparation Methods
Different types of Nutrients in Fruits and Vegetables
In the presence of bases, anthocyanidins undergo a chemical reaction that alters which wavelengths of light they can absorb and reflect. In their natural state, anthocyanidins tend to be bright and colourful, but after reacting with bases, they lose that colour and appear darker.
Methods of Determining Concentration of Chosen Nutrient
Indicator --> starch indicator
End pint- Blue/Balck
Titrant: Potassium Iodine reacts with ascorbic acid, so that no other vitamins will be calculated, hence increasing validity
Analyte: ascorbic acid and vitamin C concentration
Ensure correct washing procedures to minmise risk of errors
Factors to consider if using Titration
Acid/ Base titratiom
Visibility of colour change depending on shade of fruit or vegetable juice
Potassium Iodine changes ascorbic acid into a blue-black shade, hence how will this effect end-point determination when shade mixes with other colours?
Different types of fruits
Blueberries aren't actually blue, but deep purple, which is the colour of anthocyanin, a pigment that is especially rich in blueberries.
Different types of vegetables
Factors effecting Nutrients in Fruits and Vegetables
Growing/ farming conditions
pH of soil used
Shelf-life and how long the produce has been on shelf prior to titration
Chemical composition of fruit & vegetables
How will these effect results at the end of titration?
Number of moles required for reaction to be completed
will be determined by colour change --> colour change will occur when ascorbic acid reacts with potassium iodine, then left over potassium iodine reacts with starch indicator
Where do fruits and vegetables come from?