Measuring Sterilizing Values In Containers of Food Using Thermocouples and Biological Indicator Units ^{1, 2}

Area of Science:

• Food Science
• Microbiology
• Process Engineering

Background:

• Accurate measurement of sterilization value (F0) is crucial for ensuring food safety and product quality in canned goods.
• Traditional physical methods rely on heat penetration data, while biological indicator units (BIUs) offer a direct measure of microbial inactivation.

Purpose of the Study:

• To compare the accuracy and variability of sterilization values (F0) determined by physical (PHY) heat penetration data versus biological indicator units (BIUs).
• To assess the reproducibility of physical heat penetration measurements within experimental series.

Main Methods:

• Conducted three experimental series, each with multiple tests using thermocouples (for physical data) and BIUs in cans of peas in brine.
• Calculated sterilization values (F0) from both heat penetration data and BIU results.
• Analyzed test-to-test reproducibility for physical data.

Main Results:

• The mean difference between physical and biological sterilization values was +1.2 minutes (F0 (PHY) - F0 (BIO)).
• Physical measurements showed lower variability (coefficient of variation = 0.03) compared to biological measurements (coefficient of variation = 0.06).

Conclusions:

• Physical heat penetration data provide a reliable and less variable method for determining sterilization values in canned peas.
• The slight overestimation by physical methods suggests a conservative approach to process validation, ensuring adequate microbial inactivation.