Ash (analytical chemistry)

Ash is one of the components in the proximate analysis of biological materials, consisting mainly of salty, inorganic constituents. It includes metal salts which are important for processes requiring ions such as Na⁺ (Sodium), K⁺ (Potassium), Ca²⁺ (Calcium). It also includes trace minerals which are required for unique molecules, such as chlorophyll and hemoglobin.

For instance, the analysis of honey shows:Typical honey analysis

• Fructose: 38%
• Glucose: 31%
• Sucrose: 1%
• Water: 17%
• Other sugars: 9% (maltose, melezitose)
• Ash: 0.17%

Source: Sugar Alliance

In this example the ash would include all the minerals in honey.

Also see:

• oxides, e.g. Al₂O₃, CaO, Fe₂O₃, MgO, MnO, P₂O₅, K₂O, SiO₂
• carbonates: Na₂CO₃ (aka soda ash), K₂CO₃ (aka potash),
• bicarbonates, e.g. NaHCO₃ (aka baking soda),
• Sulfates: sulfate ash according to Ph. Eur.