Development of a novel procedure for detecting bloody milk based on an objective quantification using opal-glass...

Area of Science:

• Veterinary Medicine
• Food Science
• Analytical Chemistry

Background:

• Blood contamination in raw milk poses a significant food safety concern.
• Visual detection of blood in milk becomes unreliable at low concentrations.
• Accurate quantification of hemoglobin is crucial for reliable blood-milk detection.

Purpose of the Study:

• To enhance the reliability of blood-milk detection in raw milk.
• To quantify hemoglobin levels using visible light spectroscopy.
• To establish a reliable method for identifying blood contamination.

Main Methods:

• Visible light spectroscopy was employed, combining sodium lauryl sulfate-hemoglobin and opal-glass methods.
• Bulk milk samples were collected from different regions (Areas A, B, C) in Hokkaido.
• A calibration curve was generated using blood-milk samples (n=201) and validated on test sets (n=112, n=126).

Main Results:

• A hemoglobin concentration threshold of 0.1 g/L was identified as challenging for visual detection.
• The developed calibration curve showed high binary-classification accuracy for bloody milk.
• Sensitivities of 93.3% and 97.2%, and specificities of 94.0% and 95.6% were achieved for test sets.

Conclusions:

• Visible light spectroscopy offers a reliable method for quantifying hemoglobin in raw milk.
• The study successfully established an accurate detection method for blood contamination in milk.
• This technique enhances the safety and quality control of milk production.