CHROMATOGRAPHY
Chromatography is an analytical technique used to separate, identify and quantify components
in a mixture. It is widely applied in food science to analyze additives, preservatives, pigments,
flavor compounds and contaminants.
The technique is based on he differential distribution of compounds between a stationary phase
(solid or liquid) and a mobile phase (liquid or gas)
BASIC PRINCIPLE
Each component in a mixture interacts differently with the stationary and mobile phases.
Components that interact strongly with stationary phase move slowly.
Components that interact strongly with mobile phase move faster.
This difference in movement allows separation of compounds.
CLASSIFICATION OF CHROMATOGRAPHIC TECHNIQUES
1. BASED ON MOBILE PHASE
Gas chromatography – uses gas as mobile phase.
Liquid chromatography – uses liquid as mobile phase.
2. BASED ON MECHANISM OF SEPARATION
Adsorption chromatography – separation based on adsorption on solid
surfaces.
Partition chromatography – separation based on solubility differences.
Ion-exchange chromatography – separa5ion based on charge
Gel-filtration (size-exclusion) – separation based on molecular size.
Affinity chromatography – separation based on specific biological
COMMON TYPES USED IN FOOD ANALYSIS
TYPES APPLICATIONS
Paper chromatorapy Separation of food dyes, amino acids e.g.
colorants in beverages
Thin layer chromatography (TLC) Identification of lipids, sugars, additives e.g.
detecting rancidity in fats
Gas chromatography (GC) Volatile compounds, flavor & aroma analysis
e.g. essential oils in fruits
High performance liquid chromatography Non-volatile compounds like vitamins, sugars,
(HPLC) organic acids e.g.vitamin C in juice
Ion-exchange chromatography Amino acid or protein separation e.g protein
purification
Gel filtration Protein and polysaccharides analysis e.g.
Chromatography is an analytical technique used to separate, identify and quantify components
in a mixture. It is widely applied in food science to analyze additives, preservatives, pigments,
flavor compounds and contaminants.
The technique is based on he differential distribution of compounds between a stationary phase
(solid or liquid) and a mobile phase (liquid or gas)
BASIC PRINCIPLE
Each component in a mixture interacts differently with the stationary and mobile phases.
Components that interact strongly with stationary phase move slowly.
Components that interact strongly with mobile phase move faster.
This difference in movement allows separation of compounds.
CLASSIFICATION OF CHROMATOGRAPHIC TECHNIQUES
1. BASED ON MOBILE PHASE
Gas chromatography – uses gas as mobile phase.
Liquid chromatography – uses liquid as mobile phase.
2. BASED ON MECHANISM OF SEPARATION
Adsorption chromatography – separation based on adsorption on solid
surfaces.
Partition chromatography – separation based on solubility differences.
Ion-exchange chromatography – separa5ion based on charge
Gel-filtration (size-exclusion) – separation based on molecular size.
Affinity chromatography – separation based on specific biological
COMMON TYPES USED IN FOOD ANALYSIS
TYPES APPLICATIONS
Paper chromatorapy Separation of food dyes, amino acids e.g.
colorants in beverages
Thin layer chromatography (TLC) Identification of lipids, sugars, additives e.g.
detecting rancidity in fats
Gas chromatography (GC) Volatile compounds, flavor & aroma analysis
e.g. essential oils in fruits
High performance liquid chromatography Non-volatile compounds like vitamins, sugars,
(HPLC) organic acids e.g.vitamin C in juice
Ion-exchange chromatography Amino acid or protein separation e.g protein
purification
Gel filtration Protein and polysaccharides analysis e.g.
