It’s important to ensure that the dairy foods we eat and the beverages we drink are safe. For example, with its short transfer window - typically within 2 days - fresh milk must be subjected to a battery of tests to ensure that it complies with regulations and is safe for consumption. Processed dairy foods also undergo vigorous testing throughout the manufacturing process to ensure safety and quality.
Pathogens such as Listeria, Salmonella, and E. coli can find their way into milk throughout the supply chain, whether through faulty pasteurization, unclean machinery, or damaged packaging. Reducing time-to-result is vital to improve the efficiency of pathogen and antibiotic detection in dairy products.
Speed is Needed to Prevent Pathogenic Outbreaks
Foodborne pathogens can cause serious illness and even fatalities in populations around the world. It is imperative that dairy products are rapidly and rigorously tested before they reach the consumer, and that any contamination is traced back to its source and eliminated. Most importantly, this helps to prevent damaging outbreaks of disease, while also protecting stakeholders in the dairy supply chain from legal action by regulatory authorities such as the US FDA.
Much of the pathogen testing for dairy products involves testing environmental samples in the areas where animals are housed and products are processed, particularly in the case of Listeria. However, testing the products themselves as they move through the supply chain is also needed in order to ensure that the products reaching the market are safe for consumption.
Within PerkinElmer’s testing portfolio, Solus One™ immunoassay kits are focused on reliability and speed, which is highly important for testing in the dairy industry. By reducing the number of manual steps, and fully automating washing steps and data analysis, the latest immunoassay kits for key pathogens can deliver accurate results within 24 hours. This makes them a rapid alternative to traditional pathogen immunoassay kits.
The Solus One Listeria kit is approved for environmental samples, while the Solus One Salmonella kit is approved for both environmental and in-product testing on all dairy samples, including milk powder, yogurt and cheese.
Rapid Testing for Antibiotics
Antibiotics can potentially enter a cow’s milk when it is being medically treated. Although farmers take dairy cows out of rotation when they are undergoing antibiotic treatment, this process affects revenue, creating an urgency to get those cows back into rotation as quickly as possible.
In humans, low level exposure to antibiotics over long periods of time has been linked to the rise in antibiotic resistance. Regulatory authorities have strict rules governing the maximum residue limits (MRLs) of antibiotics in dairy products. For farmers, it is useful to have methods available for quickly testing the milk of cows that have recently stopped antibiotic treatment.
Antibiotic test strips stored at room temperature, combined with a digital reader is an ideal solution for testing on the move and in the field without being tied to electrical outputs and specific facilities. Simple testing protocols provide reliable results on the presence of many different antibiotics within minutes at or below regulatory limits.
Handheld, battery-operated, portable devices remove any ambiguity that may occur upon visual inspection. Digital readers can also store images of used test strips that can be uploaded to a dairy’s quality management system. This aids information-sharing along the supply chain and provides evidence of data integrity to auditors and regulatory authorities.
Performing the Right Test
Deciding which test is the most appropriate for different potential contaminants – and different points in the supply chain – largely depends on the regulations that need to be followed and the purpose of the test.
A farmer aiming to return a cow to milking rotation following antibiotic treatment may only need to test for a single drug, while later in the supply chain a more comprehensive analysis will be required, covering all regulated drugs. In the latter case, a test that can analyze multiple drug residues simultaneously is crucial.
In addition, it is important to select testing methods that are appropriate for the dairy product in question, whether that is fresh milk, dried milk, yogurt or cheese. Testing methods that are effective in one type of product, may not be approved for testing in other types of products. Finally, cost-effectiveness, speed and sensitivity of different testing choices must also be taken into account.
While rapid testing solutions can qualitatively detect contaminants at limits set by the EU and the UN, these types of tests may not be appropriate when a regulatory authority or third-party testing agency is confirming a suspected contamination. Sometimes more sensitive, less rapid technology such as liquid chromatography/mass spectrometry (LC/MS/MS) is needed to test for substances at extremely low levels, yielding precise concentrations.
Ensuring Safety with Speed and Accuracy
When considering how to implement rapid testing into current workflows, it is important to employ methods that cover the individual needs of the testing site in the most cost-effective manner. For pathogen testing, this may mean selecting a test that is appropriate for analyzing equipment surfaces or for analyzing in different dairy products. For antibiotic testing, selecting a testing method requires considering which antibiotics must be screened for, how quickly the results are needed, and what sensitivity is required.
In an increasingly globalized industry, it is more important than ever for stakeholders in the dairy industry to be held accountable for the safety of their produce. Rapid testing solutions for antibiotics and pathogens help these stakeholders to maintain product safety at all vulnerable points in the supply chain.