Rapid testing technologies have become increasingly common for dairy processors. There are a variety of options for rapid, accurate pathogen testing for use on different products and facilities.

Rapid testing is based on chemistries developed to detect targeted pathogens as quickly and effectively as possible. With pathogen tests that are easier to use, faster, more sensitive and more specific, they can improve the productivity, reduce risk and help the bottom line of production.



Implementation of rapid testing technologies in a dairy plant can provide a number of advantages. Faster time-to-result allows higher testing throughput, which can improve production efficiency, decrease hold times and extend product shelf life.

Traditional agar-based methods come with many challenges, according to Sailaja Chandrapati, BS, MSc, MS, PhD, senior scientist and lead product development specialist, food safety, 3M Company St. Paul, Minn. The enumeration methodologies are labor-intensive and involve the careful preparation of analyte-specific media. Sterilization of small batches of media can take an hour or more while a much longer sterilization time is needed for large volume media preparation processes and certain media contain heat labile components that require boiling for specified time periods under constant supervision.

Designed to perform comparably to the relevant ISO and FDA/BAM reference methods, the 3M Petrifilm plate enables a single step detection via a gas bubble of the lactose fermenting ability of this important class of organisms. With this tool, it is possible to get an early warning of coliform contamination within 14 hours of incubation with a confirmed positive result in 24 hours.


Cost savings

Rapid testing also allows for a faster response to adverse events, allowing production facilities to implement corrective actions that can prevent lost profits due to waste and spoilage.

“Traditional plating methods have additional, associated hidden costs, whether it’s the warehouse space required to hold all of these products while they wait for the testing results, or the safety stock and investments in inventory,” said Will Gannon, global product manager at Hygiena. “But by transitioning to a rapid method, customers can release their products up to four times faster, reducing safety stock and inventory investments, ultimately providing them with significant cost savings through a faster time to results.”

Hygiena, Camarillo, Calif., produces rapid microbial detection, monitoring and identification solutions for the food and beverage industry. The company’s Innovate System can provide results within 30 minutes and has the ability to run 96 samples at once with no secondary incubation needed. The testing can be performed on a number of products including ultra-high temperature (UHT) milks and creams, sauces, soups and beverages.

“Rapid ATP Bioluminescence truly streamlines the finished product release process, ensuring the quality of the product, while providing quicker time to results, typically by several days, in most cases,” Gannon said. “This allows the processor to rapidly identify any contamination in the products, enabling them to improve the efficiency of the manufacturing processes while also generating significant cost savings along the way. Rapid methods give customers the information they need to make an informed decision.”

Hygiena has worked with several dairy and dairy-alternative partners to test time to results for various beverages, including UHT milk, extended-shelf life (ESL) milk, oat milk and soy milk, to compare results obtained with the Innovate System and those from 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 at a 24-hour time mark in contrast to other methods which took at least 48 to 72 hours for results.


Quick detection

Conventional agar-based methods for the detection of E. coli and coliform are also time consuming and labor-intensive with confirmation steps for detecting gas production that can take anywhere from 48 hours to several days, according to Chandrapati. Coliforms are susceptible to most heat processing conditions, including pasteurization of milk, therefore their presence in heat treated foods generally indicates an inadequate heat-kill process or potential post-processing contamination.

3M Petrifilm Rapid E. coli/coliform count plate enables the simultaneous detection via a dual readout of lactose fermenting coliforms along with beta-glucuronidase producing E. coli within 18-24 hours further streamlining the complicated series of steps needed by the conventional methodologies for the detection of these organisms.

NEOGEN Corporation, Lansing, Mich., recently launched an advanced test system that automatically detects microorganisms in a fraction of the time of traditional testing methods. The Soleris Next Generation (NG) can rapidly detect a wide variety of microorganisms that can threaten the safety and quality of food and other consumer products. For example, Soleris NG can detect and enumerate yeast and mold in a sample in only 48 hours, according to the company, as compared to the three to five days needed for traditional methods.

The Soleris NG system features 32-vial incubating drawers integrated with a secure software package, and each ready-to-use vial rapidly and independently detects the presence or absence of microorganisms.

“Our improved system to detect microorganisms makes it even quicker and easier for our customers to test their products and environment — and even easier to protect their customers,” said John Adent, NEOGEN’s president and chief executive officer. “Our customers can now use a single automated system to screen consumer product and environmental samples for the presence of microorganisms — greatly simplifying that process.”

NEOGEN has also launched a quicker test to detect aflatoxin M1, a known cancer-causing toxin of concern to the global dairy industry.

NEOGEN’s Reveal Q+ for Aflatoxin M1 can detect as little as 150 parts per trillion (ppt) of the toxin in milk samples in just minutes. Aflatoxin M1 is a carcinogenic metabolite of aflatoxin B1 that is produced in the rumen of dairy cattle. The new test is designed for use with NEOGEN’s Raptor Integrated Analysis Platform, which controls the timing, temperature and reading of the test strips.

“Our addition of our test to detect aflatoxin M1 with our Raptor system simplifies the testing process for dairy processors, as they can now use our patented Raptor system to simultaneously test for this toxin, as well as dairy antibiotics,” Adent said. “Processors can simultaneously test one sample for the presence of aflatoxin M1 and classes of dairy antibiotics of known concern, including beta-lactams and tetracyclines.”

Rapid testing technology provides many operational benefits to processors including quicker release of product, as well as a quicker response to adverse events and quicker implementation of corrective actions.

“Just by streamlining their approach to microbiological testing, (processors) are able to overcome their financial challenges, especially with demand being high right now,” Gannon said. “Companies want to generate the most value for their product without compromising quality. So the fact that they’re able to test and release product significantly faster than they would using the traditional testing methods means they are able to decrease production time, which, ultimately, is the company’s goal.”