Assignment: Thermal Processing and Quality Optimisation for Juice Pasteurisation
Scenario
You have been hired as a consultant by a juice manufacturing company to design an optimal pasteurisation system for a new juice product. The company’s goals are to ensure microbial safety (achieving a 6-log reduction) while maintaining the desired taste quality, with a minimum Cook Value (Cv). They are also concerned about operational efficiency, fouling risks, and exploring the integration of biotechnology in juice processing.
Assignment Objectives
By completing this assignment, you will:
1. Perform. microbial inactivation and quality calculations.
2. Recommend an appropriate heat exchanger type and fouling management strategies.
3. Evaluate biotechnological advancements in juice processing.
4. Reflect on the key trade-offs in designing a food processing system.
Assignment Tasks
Task 1: Microbial Safety and Quality Retention (60%)
The factory manager has provided data on microbial counts at various temperatures and times for the juice being processed. They have also specified that the desired taste quality requires a minimum Cook Value (Cv).
Raw Data for Microbial Inactivation:
|
Time
|
Microbial Count
|
Microbial Count
|
Microbial Count
|
Microbial Count
|
|
(min)
|
(CFU/ml) at 65°C
|
(CFU/ml) at 70°C
|
(CFU/ml) at 75°C
|
(CFU/ml) at 80°C
|
|
0
|
1,000,000
|
1,000,000
|
1,000,000
|
1,000,000
|
|
1
|
500,000
|
250,000
|
125,000
|
62,500
|
|
2
|
250,000
|
62,500
|
15,625
|
7,812
|
|
3
|
125,000
|
15,625
|
1,953
|
488
|
|
4
|
62,500
|
3,906
|
244
|
30
|
|
5
|
31,250
|
977
|
31
|
2
|
|
6
|
15,625
|
244
|
4
|
<1
|
Consider Zc=35°C
As part of your role, the company expects you to:
1. Safety Assurance:
o Provide recommendations on the thermal processing design that will guarantee the product achieves pasteurisation microbial safety (a 6-log reduction).
o Use the provided data to support your recommendations and demonstrate your reasoning.
2. Taste Quality:
o Identify the process condition where the desired taste quality can be maintained.
o Explain the trade-offs between achieving microbial safety and preserving taste quality, and propose a solution that balances both goals.
The factory manager expects a summary table or chart highlighting your key findings, along with a clear justification for your recommendations.
Task 2: Heat Exchanger Recommendation and Fouling Management (20%)
The engineering team has requested recommendations on the type of heat exchangers that should be used in the juice pasteurisation system. The chosen system must optimise microbial safety, taste quality retention, and operational efficiency while managing fouling challenges.
Specifically, they want you to:
1. Heat Exchanger Selection:
o Recommend a suitable type of heat exchanger for the pasteurisation system.
o Justify your choice
2. Fouling Management:
o Discuss potential fouling risks in the recommended heat exchanger system
o Propose a Cleaning-in-Place (CIP) protocol tailored to the chosen heat exchanger type. Include:
§ Cleaning agents.
§ Recommended temperature, flow rates, and duration.
§ Frequency of cleaning based on operational use.
The engineering team expects detailed justifications for your recommendations, supported by references to operational performance and practical considerations in juice manufacturing.
Task 3: Biotechnology in Juice Processing (15%)
The product development team is considering integrating biotechnological advancements into their juice processing pipeline to improve product stability and nutritional content.
You are tasked with:
1. Identifying two biotechnological approaches that could be applied in juice processing.
2. Evaluating the benefits and limitations of these approaches, including their feasibility in a commercial production setting.
The team expects a short report summarising your recommendations, including a discussion of potential implementation challenges.
Task 4: Conclusion and Reflection (5%)
The CEO has asked for a brief conclusion summarising your recommendations for the pasteurisation system. They are also interested in your personal reflection on the following:
1. What trade-offs did you face when balancing safety, quality, and operational efficiency?
2. What insights or skills did you gain from addressing these challenges?
This section should be presented as a short executive summary (approximately 300 words).
Submission Guidelines
• Submit a written report of up to 3,000 words, excluding tables and diagrams.
• Include all diagrams, tables, and justifications for your recommendations.
• Cite any references used in your analysis.
• Submit your report via the Canvas submission portal by 10th of February 2025