Method for Predicting Minimum Detectable Residual Alkaline Phosphatase in High-Temperature, Short-Time Processed...

Area of Science:

• Food Science
• Dairy Technology
• Analytical Chemistry

Background:

• High-temperature, short-time (HTST) processing is crucial for dairy product safety.
• Residual alkaline phosphatase (AP) can indicate inadequate pasteurization.
• Accurate detection of residual AP is essential for quality control.

Purpose of the Study:

• To develop and validate a method for determining minimum detectable residual alkaline phosphatase (E₀) in HTST-processed milk, cream, and buttermilk.
• To investigate the correlation between phosphatase reactivation and E₀.
• To propose a predictive model for E₀ in liquid dairy products.

Main Methods:

• HTST-processed dairy products were spiked with varying percentages of raw milk.
• Samples underwent a differential test to assess alkaline phosphatase reactivation.
• Phosphatase activity was quantified using a rapid colorimetric assay.
• Experimental data were analyzed using a linear statistical model.

Main Results:

• A high correlation (rank correlation coefficient = 0.956, p < 0.05) was observed between experimental and computed values for E₀.
• E₀ values increased with greater phosphatase reactivation.
• Residual alkaline phosphatase was generally higher in cream compared to milk.

Conclusions:

• The proposed method accurately predicts the minimum detectable residual alkaline phosphatase in HTST-processed dairy products.
• The extent of phosphatase reactivation directly influences the minimum detectable level.
• This predictive method enhances quality control for HTST dairy products.