1. Acids and Bases (Acidity and Alkalinity)

2. Acidity Have more hydrogen ions (H+) Make foods acid Examples include:
Lemon juice
Vinegar
Other characteristics of acidic foods:
Sour taste
Sting when touched
React strongly when combined with metals
A Acids and Bases

3. Bases /Alkalinity Have more hydroxide ions (OH)
Makes foods more alkaline
Examples include:
Soap
Egg whites
Other characteristics of a alkaline:
Bitter taste
Feel slippery to touch
Do not react when combined with metals
A Acids and Bases

4. Acids and Bases identified by:
Taste sour
Turn red when tested
pH between 0 and 6.9
BASES
Taste bitter
Turn blue when teted
pH between 7.1 and 14
A Acids and Bases

5. Effects of pH on food
pH is a measure of acidity or alkalinity of food.
Changes in pH effect quality.
Color
Texture
Stability
Changes in pH effect safety
Foods are generally acidic (pH less than 7.0)
Low acid foods have a pH between 4.6 and 7.0 (potentially hazardous food)
High acid foods have a pH of 4.6 or less. (non-potentially hazardous food)
A Acids and Bases