Processing Magazine

DNA amplification, bioluminescence and safety in food processing

June 4, 2012

It is estimated that there are as many as two million to four million cases of salmonellosis every year in the U.S. alone. Indications are that combating this and other pathogens is going to take food processors — if they aren’t already there — into the world of molecular biology.

Not long ago, the 3M Molecular Detection Assay – Salmonella, from 3M Food Safety, St. Paul, Minn., received AOAC-PTM Certification from the AOAC Research Institute’s Performance Tested Methods program. An “assay” is a kind of procedural test.

What it means, Nicki Montgomery, a manager with 3M Food Safety, tells Processing, “is that we are continuing down the path toward being an ‘official method’ for testing labs — whether the food processors’, third parties’ or governments’ —  that want molecular-level accuracy in the detection of dangerous pathogens, including E. Coli 0157 and Listeria, in addition to Salmonella.”

The globalization of the food industry and the growing prevalence of highly processed foods, amongst other trends, is making food safety a “global mega trend” based on demand from both developed and developing worlds. “3M wanted to participate in this growing market,” Montgomery says. “Different regions in the globe are at different stages of food safety regulation, but all are committed.”

The newly approved testing method is based on the 3M Molecular Detection System, which 3M says uniquely combines isothermal DNA amplification and bioluminescence detection. First introduced in late 2011, the 3M system already has been “sold on every continent and in thirteen countries. We’re working with hundreds of customers on trials and thousands in educating the market,” Montgomery says. 

DNA amplification is the production of multiple copies of a sequence of DNA and has primarily medical applications. Bioluminescence has come into widespread use for quantitative determination of specific substances in biology and medicine.

Combining the two technologies is said to make testing much simpler than has ever been the case before and is said to be suitable for produce, meats, processed foods, pet foods and processing-related environmental samples.

“In our evaluation of the Listeria species assay, we liked the small footprint of the system as well as the quick delivery of results after sample enrichment,” Dr. Martin Wiedmann, a professor in Cornell University’s Department of Food Science, said when the system was introduced. It “definitely illustrates the potential of isothermal methods for rapid detection of foodborne pathogens.”

The AOAC certification is a step toward being an officially approved testing method. “This method validation is an important milestone, constituting the first of what we believe will be many confirmations of a robust and capable technology,” DeAnn Benesh, regulatory affairs specialist with 3M Food Safety. “Evaluation of Salmonella, and other pathogens using this technology, continues to be very promising.”

Concludes Montgomery: “These two technologies have never been brought together before and we’ve done so to bring molecular-level accuracy to food processors without a complex process.”