Chapter 13 Acids and Bases: The Molecules Responsible for Sour and Bitter. Sourness in foods is caused by acids, molecules that release protons. The chemical opposite, bases, are all around us. Introduction. Acids do dissolve metals, but not with the speed alluded to in movies or television.
Acids and Bases: The Molecules Responsible for Sour and Bitter
The chemical opposite, bases, are all around us.Introduction
Acids do dissolve metals, but not with the speed alluded to in movies or television.Properties of Acids
Slippery feel in movies or television.
Ability to react with acids to form water and a salt in neutralization reactions
Bases turn litmus paper blue.Properties of Bases
Pure water with H3O+ concentration of 1 x 10-7 has a pH of 7.
Naturally occurring citric and other acids in acidic foods offer spoilage resistance.Common Acids: Citric
Fermentation with lactic- acid-forming bacteria helps preserve low acid foods like cucumbers and cabbage.
This technique is called pickling.Lactic Acid
pH = - log [H3O+]
[H3O+] = 10-pH
Acidic solutions (pH 0-6 or < 7) [H3O+] > 1x10-7 M
Neutral solutions (pH = 7) [H3O+] = 1x10-7 M
Basic solutions (pH 8-14 or > 7) [H3O+] < 1x10-7 M