Food Safety
3 Reasons Rapid Microbiological Testing Matters for UHT, ESL and Dairy-Alternative Beverages
Why Shelf-Stable and Extended Shelf-Life Dairy Products Need Robust Testing
As demand grows for UHT, ESL and dairy-alternative beverages, manufacturers are under increasing pressure to extend shelf life, protect product quality and release finished goods with confidence.
Thermal processing and aseptic packaging help reduce microbial risk, but they do not remove the need for robust final product testing. Contamination, spoilage organisms, post-process handling issues and matrix complexity can still affect product safety, quality and release timelines.
Rapid microbiological testing gives dairy processors a faster route to evidence-based release decisions, helping reduce hold times, warehouse pressure and the cost of delayed product release.
The Aseptic Food & Beverage Market Outlook
The global aseptic food and beverage packaging market is expected to reach $35 billion by 2025, partially due to the increased popularity of dairy products. This has fueled demand for products with longer shelf lives and that can be stored at room temperature. While ideal for many foods and beverages, aseptic processing poses both advantages and disadvantages for milk and milk-derived beverages. Milk products are generally processed by thermal methods, such as pasteurization, as has been done for decades, which limits shelf life, chilled distribution, and refrigerated storage after purchase. Plus, the shelf life and quality of pasteurized milk can be affected by spore load in raw milk, pasteurization conditions, contamination, and, particularly, distribution temperature.
UHT vs ESL Milk: What’s the Difference?
To overcome these challenges, new processing methods are being evaluated to further reduce or eliminate microbes that can cause food spoilage and disease. Two thermal processing methods are UHT (Ultra High Temperature) and UP (Ultra-Pasteurization). While UHT milk has been around for a while, it is now experiencing a resurgence, along with Extended Shelf Life (ESL/UP) milk, which is playing an important role in shaping dairy markets as they develop new processing and packaging methods. However, even with improvements in processing methods, there can be advantages and disadvantages to manufacturing UHT and ESL milk products.
Advantages of UHT milk include:
- Less processing time
- Extended shelf life
- Reduced microbial load
- Safer than other milk
- No need for refrigeration for storage
- Cheaper/wider variety of packaging options
Disadvantages of UHT milk include:
- Altered milk flavor/quality
- Decreased nutritional value
- Expensive process- complex, technical equipment, high energy use
- Anonymous milk origin due to batching
Advantages of ESL milk include:
- Organoleptic properties similar to pasteurized milk
- Extended shelf life
- Less expensive than UHT processing
Disadvantages of ESL milk include:
- Potential for contamination
- Potential for flavor issues
- Texture and appearance defects after prolonged storage
- Difficulty in remaining competitive (operational complexities)
How Rapid Microbial Screening Supports Dairy Quality Control
Second, while aseptic processing is a safe, high-quality, cost-effective method for food processing, there are still risks of contamination during manufacturing and production. To address this risk, food manufacturers must test each product for sterility before releasing it for sale. Traditional methods can take up to 15 days to yield results and are prone to error due to manual sample handling. These standard plating methods require different enrichment media and long incubation times (7-14 days) and long detection/confirmation times (2-5 days) to target aerobic or anaerobic bacteria and yeast or mold. Other testing methods, such as pH and visual inspection, have similar risks of error, as not all microorganisms cause a pH shift, and visual inspection can miss low levels of contamination. To reduce time-to-results and streamline laboratory testing, a rapid method is needed. The Innovate™ Rapid Microbial Detection System from Hygiena® offers both. Results can be obtained in less than 30 minutes, and 96 samples can be run at once with no secondary incubation required. In addition, the testing can be performed on a diverse product matrix - from UHT milks and creams to sauces, soups and broths, juices and beverages.
Rapid testing allows manufacturers to confirm the quality of the final product and release it to market quickly. Cost savings go beyond the rapid release of products - it means less safety stock, lower warehouse costs, and increased confidence in product safety.
Ensure Your Method Supports Multiple Matrices
Third, to address microbiological risks in final products, it is ideal to have rapid testing that can be used across multiple matrices, specifically those manufactured in any of your food processing facilities. These methods should be verified and validated to ensure testing is consistent, accurate and a true reflection of microbial load in any product package before it is distributed for consumer use. Tied to the validation is the need for the most rapid testing that fits your requirements.
When it comes to the Innovate System, Hygiena worked with several dairy and dairy-alternative partners to test time to results for various beverages (UHT milk, ESL milk, oat milk and soy milk) to determine if results obtained with the Innovate System are superior to traditional culture methods or pH testing with respect to the level of detection and shortest time to results.
In all cases, for all microorganisms tested (except for Clostridium sporogenes in ESL oat milk), the Innovate System was able to detect low spike levels (~10 CFU per pack) at a 24 hour time mark. RLU values in the spiked products exceeded the RLU thresholds for the uncontaminated product, set at three times the baseline value. Read the details of each study here:
As a result of rapid detection of low levels of contamination at 24 hours, the cost savings for any facility is significant. While QC costs are similar, the investment in finished goods and safety stock are significantly reduced along with the warehouse space costs. In addition, positive release of product helps prevent recall cost and protect the brand that adds significant benefit to the introduction of a rapid testing system such as the Innovate System. As an additional advantage, high-volume facilities can automate product sampling using the Innovate Autosampler III. Learn more about the Innovate System and the Autosampler III here.
In Summary
- Full microbiological testing results must be obtained before releasing product for sale. More rapid results mean less holding time, less warehouse space needed and quicker release for sale.
- Reducing time to results with the ability to test 96 samples in 30 minutes means you can screen for multiple microorganisms that may be present as contaminants in final product at the same time and quickly. In addition, for large sample volumes, sample processing can be automated with the Innovate Autosampler III.
- Validated methods for dairy and dairy-alternative products can have results in 24 hours rather than in days as with traditional methods. In addition, numeric values can help indicate the level of contamination for further tracking and trending. Overall, cost reduction and reduced time-to-results are essential for dairy and dairy-alternative food processors, simplifying operations.
Want to understand how rapid microbial screening could support your UHT, ESL or dairy-alternative release process? Explore Hygiena’s dairy testing solutions or speak with our team about your product matrix, workflow and release requirements.
Looking to learn more? Read our article on the savings you can see - Faster Results, Lower Costs, Improved Risk Mitigation, then check out our whitepaper about UHT vs ESL beverages: Advantages, Disadvantages and a Unified Testing Platform.
