1. Bioluminescence: How scientists use food microbiology to ensure your beverage is safe
particles - where science matters
  • Bioluminescence: How scientists use food microbiology to ensure your beverage is safe

    By Janna Fischer, 3M Storyteller

    Food microbiology testing

    • Those carbonated, sugary soft drinks? They’re quickly becoming a thing of the past.

      Today’s consumers are instead reaching for drinks formulated with fewer, simpler ingredients. Teas, raw juices and plant-based waters are becoming the drinks of choice for many Americans.

    • How food microbiology is making safer beverages

      Part of the trend toward healthier beverages means people are looking to add more milk and more natural juice into what they drink. Food processors are meeting the demand. But when you sell things with fresh ingredients, it becomes more of a challenge to keep them fresh – and safe – for long periods of time.

      “It’s easy to throw a lot of sugar or acid in there – those beverages will last for years,” says Eric Amann, global marketing manager, 3M Food Safety. “But the minute you start putting fresh fruit and milk into the mix, that’s when it’s easier for the bacteria to spoil it and make it unsafe for consumption. You need some kind of treatment to keep those drinks on the shelf longer.”

      To extend the shelf life of these products, food companies often treat the liquids with Ultra High Temperature (UHT) processing. This type of processing heats the products to temperatures of up to 140 degrees for a handful of seconds. The objective? To completely rid the liquids of any bacteria, making them shelf-stable for extended periods of time. And when it comes to food processing, just a few extra days of shelf life can be a substantial benefit to the producer, the retailer and the consumer.

       

      But how do food processors test to ensure their UHT products have been wiped completely clean of any dangerous microorganisms before sending them out into the marketplace?

    • Food microbiology and adenosine triphosphate (ATP) bioluminescence technology

      Enter adenosine triphosphate (ATP) bioluminescence technology

      Remember learning about bioluminescence in science class? It’s the chemical reaction that emits light within a living organism – fireflies are probably the best-known example. ATP is the biological way in which fireflies – and all living organisms – store and use energy. And, because it is present in all living things, ATP can be used as a universal marker for biological contamination across all microorganisms, too.

      Scientists at 3M have tapped into this powerful marker to create a system that utilizes ATP bioluminescence technology to test for microorganisms in UHT and Extended Shelf Life (ESL) processed products.

      Since ATP is a proxy for how many bacteria are present, the 3M system determines how much ATP is left in the sample after it’s been heat processed.  It also recognizes the spoilage microorganisms that can take a beverage from desirable to harmful. Those spoilers can include aerobic bacteria, anaerobic spore formers, yeasts, molds and lactic acid bacteria.

    • ATP molecule for food microbiology testing
      ATP molecule

      Here’s how it works

      Two types of ATP exist in the world – microbial ATP that’s found in all living things and non-microbial ATP that’s found in nonliving things such as dirt. Since food processors don’t want to have a false reading from the non-living things, the 3M system works by first killing all the non-microbial ATP in the sample. Once all the non-microbial ATP is removed, it cuts open the bacteria that are left and releases the ATP that’s inside the remaining bacteria.

      After that, another chemical is added that causes the free ATP derived from the bacteria to glow like a firefly. In this case – unlike in the case of the firefly – glowing equals a positive result, meaning the product is contaminated.

      “The system gives food processors accurate and real-time pass/fail testing results on their products in less than 30 minutes,” says Eric. “And the confidence of knowing that no critical organisms went undetected.”

      The test works on a wide variety of UHT and ESL beverages, including milk and creamers; dairy substitutes like soy, rice, almond and coconut milks; smoothies formulated with milk and juice, teas, soups and broths; and nutrition shakes and baby formula.

      The other thing food processors like about 3M’s benchtop system? It speeds up the testing process by two to five days compared to traditional methods like agar plates and pH measurement, which can be unreliable and require lengthy incubation periods. A faster result allows food processors to release their products to the marketplace sooner. And it reduces storage space and costs, providing faster inventory turns and greater flexibility and responsiveness to their customer needs.

      So, now you can feel even better about foregoing that sugary soft drink and opting instead for that fresh, healthy beverage of choice.

      Cheers to that.

      EXPLORE FOOD SAFETY