Introduction to Food Analysis
Key concepts, objectives, and common techniques used to evaluate the composition, quality, safety, and nutritional value of foods.
1. What Is Food Analysis?
- Definition – Scientific examination of food items to determine their chemical, physical, microbiological, and sensory properties.
- Purpose – Ensure safety, verify label claims, support product development, monitor quality, and comply with regulations.
- Scope – Raw materials, processed foods, beverages, supplements, and packaging interactions.
2. Major Objectives
| Objective |
Why It Matters |
Typical Parameters Measured |
| Safety |
Protect public health |
Pathogens, toxins, pesticides, heavy metals, allergens |
| Quality |
Maintain brand reputation |
Moisture, fat, protein, ash, color, texture |
| Nutritional labeling |
Meet regulatory labeling requirements |
Macro‑ and micronutrients, vitamins, minerals, fiber |
| Authenticity & Adulteration detection |
Prevent fraud |
Species identification, geographic origin, adulterant markers |
| Shelf‑life & stability |
Optimize storage & distribution |
Oxidation products, microbial growth, moisture migration |
3. Core Analytical Areas
3.1. Proximate Composition
- Moisture – Oven drying, Karl Fischer titration.
- Ash (minerals) – Combustion in a muffle furnace.
- Protein – Kjeldahl, Dumas, or Bradford assay.
- Fat – Soxhlet extraction, acid hydrolysis, or gas chromatography (GC).
- Carbohydrates – Calculated by difference or measured by HPLC (sugars, starch).
3.2. Micronutrient Analysis
- Vitamins – HPLC with UV/Vis or fluorescence detection; LC‑MS/MS for trace vitamins.
- Minerals & Trace Elements – Atomic absorption spectroscopy (AAS), inductively coupled plasma‑optical emission spectrometry (ICP‑OES), or ICP‑mass spectrometry (ICP‑MS).
3.3. Food Additives & Contaminants
- Preservatives, sweeteners, colorants – HPLC, capillary electrophoresis.
- Pesticides & Herbicides – QuEChERS extraction + GC‑MS or LC‑MS/MS.
- Mycotoxins – LC‑MS/MS, ELISA kits.
- Heavy Metals – ICP‑MS, AAS.
3.4. Microbiological Analysis
| Test |
Target |
Common Methods |
| Total Plate Count |
Overall bacterial load |
Plate count on agar |
| Coliforms / E. coli |
Indicator organisms |
Petrifilm, Most Probable Number (MPN) |
| Salmonella, Listeria, Campylobacter |
Pathogens |
ISO/BS EN 6579, selective enrichment + PCR |
| Yeasts & Molds |
Spoilage |
Plate count on selective media |
| Spoilage enzymes (e.g., lipase) |
Quality deterioration |
Spectrophotometric assays |
3.5. Physical & Sensory Evaluation
- Texture – Texture profile analysis (TPA), penetrometry.
- Color – Colorimeter, spectrophotometer (CIE Lab*).
- Viscosity – Rheometer, viscometer.
- Sensory panels – Descriptive analysis, hedonic testing, trained vs. consumer panels.