Studying heating effects on desi ghee obtained from buffalo milk using fluorescence spectroscopy

Area of Science:

• Food Science
• Spectroscopy
• Analytical Chemistry

Background:

• Desi ghee, a clarified butter, is a staple in South Asian cuisine.
• Understanding its thermal stability is crucial for food safety and nutritional value.

Purpose of the Study:

• To characterize the thermal deterioration of buffalo milk desi ghee.
• To identify safe temperature ranges for cooking and frying using fluorescence spectroscopy.

Main Methods:

• Utilized fluorescence spectroscopy to analyze non-heated and thermally treated desi ghee samples.
• Employed excitation wavelengths of 280 nm and 410 nm for spectral analysis.
• Applied Principal Component Analysis (PCA) to classify samples based on temperature effects.

Main Results:

• Identified specific fluorescence emission bands corresponding to vitamin D, vitamin K, conjugated linoleic acid (CLA) isomers, vitamin A, and chlorophyll.
• Determined that desi ghee is relatively stable between 140-170°C.
• Observed significant spectral variations and increased oxidation products (peak at 552 nm) with rising temperatures, indicating deterioration of nutritional components.

Conclusions:

• Fluorescence spectroscopy is effective for assessing ghee's thermal degradation.
• Temperatures up to 170°C are suitable for cooking without significant loss of molecular composition.
• Higher temperatures lead to the deterioration of vitamins, CLA isomers, and chlorophyll.