Rapid method for cholesterol analysis in bovine milk and options for applications

Area of Science:

• Analytical Chemistry
• Food Science
• Dairy Science

Background:

• Accurate cholesterol quantification in raw milk is essential for nutritional and quality assessments.
• Existing analytical methods may have limitations in terms of speed, cost, or complexity.
• The need for a robust and accessible method for routine raw milk analysis is recognized.

Purpose of the Study:

• To adapt and validate a colorimetric technique for the quantitative analysis of cholesterol in raw milk.
• To assess the performance characteristics of the adapted method.
• To identify critical pre-analytical factors influencing cholesterol measurement accuracy.

Main Methods:

• Adaptation of a standard colorimetric assay for raw milk matrix.
• Evaluation of assay performance including intra-assay and inter-assay coefficients of variation (CV).
• Assessment of linearity and recovery of spiked cholesterol in raw milk samples.

Main Results:

• The adapted colorimetric method demonstrated satisfying performance quality.
• Mean intra-assay CV was 4.8% and inter-assay CV was 9.1%.
• Linearity was confirmed between 0 and 7 mm, with cholesterol recovery ranging from 98.1% to 106.3% for spiked samples.

Conclusions:

• The developed colorimetric technique provides a reliable method for raw milk cholesterol analysis.
• Accurate results are contingent upon performing milk fat extraction within 48 hours of sampling.
• Variations in milk cholesterol composition during the milking process must be considered during sample collection to ensure representativeness.