Why is it challenging to analyze food samples?

As food/ food components are very complex in nature, analysis of foods is a very challenging sector. Food samples often come with heavy matrices due to the presence of primary metabolites like carbohydrates, lipids and proteins.

Besides this, there may be other complex components which may interfere with the analyte of interest. A number of analytical instruments are used for the analysis of food samples.

If we talk about chromatography, instruments like HPTLC, HPLC and GC are most commonly used depending on the aim/type of analysis.

HPTLC technique can be used not just for traditional food samples but also for recent categories of food samples like functional foods, nutraceuticals and dietary samples.

The Role of HPTLC in Food Analysis

CAMAG HPTLC, a very flexible, cost-effective and fast technique is very useful for the analysis of food samples.

Validated HPTLC methods fulfil the requirements for reliable food analysis in many food fields.

HPTLC is a modern version of TLC wherein the principle remains the same but the practice is different. HPTLC is now the official technique as per United States Pharmacopoeia (USP) and it is GLP/USP/EP compliant chromatographic technique.

What type of food analysis can be performed by HPTLC?

• Qualitative and quantitative analysis of markers present in the sample. Mostly for components of food samples like colours, additives and preservatives.
• To test the safety of food samples e.g. aflatoxin, and ochratoxin analysis.
• Limit tests e.g. to check the permissible limit of additives e.g. sorbic acid in cheese
• To check adulteration in food samples e.g. melamine in milk, argemone oil adulteration in mustard oil.

Advantages of HPTLC in food analysis

• HPTLC is a high throughput technique, more than 100 samples can be run per day with minimal analysis cost.
• Enable multiple detections (UV visible photo documentation with CAMAG TLC visualizer, derivatization, scanning with TLC scanner for quantification, spectra,  MS)
• Enables parallel chromatography under identical environmental conditions
• Enables selective and simultaneous derivatization by a myriad of chemical reagents
• Gives more information about an unknown (also what is left on the adsorbent at the origin.
• Enables toxicity-directed detection.

Let us see one example of HPTLC application in food analysis.

Quantification of Capsaicin in chilli powder by HPLTC method

Capsaicin is the chemical in chilli that makes them spicy.  It is the main bioactive plant compound in chilli peppers, responsible for their unique, pungent taste and many of their health benefits.

Capsaicin is used as an analgesic in topical ointments and dermal patches to relieve pain, backache, strains and sprains typically in concentrations between 0.025% and 0.1%.

The method was developed for the identification and quantification of capsaicin in a given chilli powder sample. 

After derivatization with vanillin sulphuric acid, a bluish colour band of capsaicin was detected at Rf 0.34. Multilevel quantification was carried out and it was found that it is present at 0.10% in chilli powder.

Anchrom Enterprises Pvt. Ltd is one of the leaders in HPTLC analysis in India. Please contact us at lab@anchrom.in for HPTLC analysis of plant extracts, food, drugs, ingredients in cosmetics, and forensic science.