Thermal process optimisation

Summary

In this presentation, David Whittaker, Process Specialist at Camden Bri, explores the principles of thermal process optimization based on validation study data. He emphasizes the importance of meeting food safety standards while minimizing over-processing to preserve product quality, nutritional value, and reduce energy waste. Key concepts such as lethality, safety factors, and the optimal use of heating and cooling phases are discussed, with a focus on refining the process to achieve the target lethality efficiently. The goal is to strike a balance between food safety and process optimization for improved performance.

Takeaways

• 😀 Thermal process validation ensures food safety by measuring the environment, product temperatures, and accumulated lethality.
• 😀 Thermal process optimization aims to balance food safety with minimizing over-processing to preserve product quality.
• 😀 Over-processing can negatively impact product quality, nutritional value, and waste energy in the production process.
• 😀 The goal of thermal process optimization is to determine the optimal time and temperature to meet safety standards without exceeding necessary levels.
• 😀 A key part of validation involves setting a minimum lethality threshold (e.g., F0 = 3 minutes) to ensure food safety.
• 😀 The safety factor (SF) determines the margin of safety by comparing the target lethality with the minimum required lethality.
• 😀 The SF can vary based on process consistency and product risk, with higher safety factors required for more variable processes.
• 😀 In thermal process optimization, data from validation studies helps identify areas for reducing process time without compromising safety.
• 😀 Only certain phases of the thermal process (such as the cook phase) contribute to lethality accumulation, while others (like cooling) are not typically used.
• 😀 By analyzing validation data, manufacturers can optimize the process, reducing time and energy spent while still meeting safety standards.

Q & A

What is thermal process optimization, and why is it important?

Thermal process optimization involves refining the time and temperature used in food processing to balance safety, quality, and efficiency. It's important because it ensures food safety while minimizing over-processing, which can negatively affect product quality and waste energy.

How does thermal process optimization differ from thermal process validation?

Thermal process validation confirms that a product has met the minimum safety standards, while optimization goes a step further to ensure that the process is as efficient as possible, avoiding over-processing and preserving quality.

What role does the lethality measure play in thermal process optimization?

Lethality is a measure of the heat’s effect on a product over time. It accumulates as the product is exposed to heat, and the process is optimized by ensuring sufficient lethality for safety without overexposing the product, thus preventing quality degradation.

Why is it important to minimize over-processing during thermal treatment?

Over-processing can lead to a loss of nutritional value, degrade the product’s quality, and waste energy and time. Minimizing over-processing helps maintain product integrity while improving efficiency.

What does F0 represent in the context of thermal processing?

F0 represents the lethality target for sterilization, typically defined as the minimum time-temperature combination required to achieve safe processing. For example, a typical F0 target for sterilization is three minutes.

How is the safety factor determined, and what role does it play in process optimization?

The safety factor is determined through a risk assessment and depends on how consistent and repeatable the thermal process is. It ensures that the thermal treatment exceeds the absolute minimum lethality by a specific margin to account for variability in the process.

Why might a safety factor of 3 or 4 be used in some cases?

A higher safety factor, such as 3 or 4, is used when the process is less consistent or has more variability. It ensures the product is safely processed even in less controlled environments.

Which phase of the thermal process is typically the most controlled, and why?

The cooking phase is typically the most controlled because it involves steady heating within the processing equipment, whereas the cooling phase is more difficult to regulate and often occurs outside the controlled environment.

Can the cooling phase be used in the calculation of lethality for thermal process optimization?

Typically, the cooling phase is not used to calculate lethality because it is less controlled and can result in unregulated temperature changes. The heating or cooking phase is generally the most reliable for this purpose.

How can thermal process optimization lead to energy savings?

By reducing unnecessary cooking time or adjusting the heating cycle, the process can be optimized to use less energy. This ensures that the product receives just enough heat to achieve the desired safety and quality without excess energy expenditure.