New Fluorescence Spectroscopy Method Exposes Complex Adulteration in Cow Ghee
Researchers at the Central University of Tamil Nadu have pioneered an analytical technique to quantify multiple fats in cow ghee simultaneously. This low-cost method detects contaminants like beef tallow and vanaspati at levels as low as 1% concentration.
Innovative Detection of Multiple Contaminants
Scientists from the Department of Chemistry at the Central University of Tamil Nadu (CUTN) have successfully developed a high-precision methodology to identify and measure several adulterants in cow ghee. Led by Dr. John Prakash, alongside researchers Anjali Rajesh and Anupama Vijayan, the team utilized Angular Sweep Total Fluorescence Spectroscopy (ASTFS) to establish a baseline fluorescence fingerprint for pure clarified butter. The breakthrough addresses the growing issue of food fraud where more than one foreign fat is introduced into a single product.
The Mechanics of ASTFS and MCR–ALS
Traditional testing often struggles to differentiate between various foreign fats in a single sample. The CUTN approach overcomes this by combining ASTFS with Multivariate Curve Resolution – Alternating Least Squares (MCR–ALS) chemometric analysis. This algorithm resolves intricate spectral variations created when fats such as pork lard, beef tallow, and hydrogenated vegetable oil (vanaspati) are blended into ghee. Key technical benchmarks of the method include:
- Precision: Capable of identifying and quantifying individual adulterants at concentrations as low as 1% (w/w).
- Sample Efficiency: Requires a minimal quantity of only five micrograms per test.
- Analytical Power: Distinguishes the specific spectral contributions of each foreign component within a mixture.
- Robustness: Successfully validated against both controlled laboratory samples and established commercial brands.
Economic Viability and Future Field Application
While the process currently requires specialized laboratory hardware, its operational efficiency offers a significant advantage over slow chromatographic techniques. An analysis costs approximately ₹50 per sample, positioning it as a financially sustainable option for routine screening. The CUTN team is now focused on miniaturizing this technology. The objective is to produce portable handheld devices that will allow regulatory agencies, food safety inspectors, and the dairy industry to perform on-site, non-destructive quantification of ghee purity without delay.
Source: The Hindu — Cities
