1. How scientists got creative to battle seemingly innocent water droplets that can contaminate your food
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  • How scientists got creative to battle seemingly innocent water droplets that can contaminate your food

    By Janna Fischer, 3M Storyteller

    Worker applying film to pipe

    • The bathroom mirror during a steamy shower. An ice-cold glass of lemonade as it “sweats” on a sweltering summer day.

      Your eyeglasses when you exit a cold, air-conditioned building and head outdoors into the sticky humidity.

      Condensation. We look at this simple physical change and see a common occurrence in our everyday lives.

      But when scientists at 3M look at it, they see an opportunity for innovation.

    • Condensation dripping from a pipe

      What a difference a drop makes

      Food processing facilities go to great lengths to keep our food safe. They need to be fastidious about the cleanliness of their operations, so equipment is cleaned and sterilized regularly.

      In refrigerated food processing facilities – including plants that process meats and ready-to-eat items like frozen pizza – temperatures need be controlled to ensure the food is safe. When the cool air temperature in the facility mixes with the high heat and water used during the sanitation process, the intermittent high humidity conditions can generate literal clouds of fog. This condensation clings to every surface – from floors to overhead pipes – with the potential to drip onto surfaces it shouldn’t.

      Those innocent-looking beads of condensation aren’t always as innocuous as they appear – those droplets can become dribbles of contaminated moisture. Dealing with the condensation burden is a necessity for facilities. But it’s not always easy.

      “Traditional methods to remove condensation include sending out crews of people with big squeegees on hollow poles,” explains Jim Medek, a retired business development manager, 3M R&D. “The squeegees collect the condensation off the pipes and surfaces and transport it to somewhere else. But if the squeegees are indeed wiping off contaminated moisture, they can be a carrier of contamination, transporting microorganisms to different locations.”

    • Microscopic image showing microreplication

      Scientists at 3M wanted to figure out a way to help cooled-food processors deal with the condensation load by reducing the labor associated with the removal of condensation droplets formed during the sanitation process. So they leveraged their innovative microreplication technology to develop a film that can be adhered to surfaces in the facilities – like overhead pipes – to help reduce condensation.

      First pioneered by 3M in the 1960s, microreplication is the process that involves layering surfaces like plastic sheets with precisely sculpted, cloned shapes. Scientists found that these exact, minuscule pyramids altered the physical, chemical and optical properties of the plastic surfaces, often in amazing ways.

      3M scientists used microreplication to create tiny grooves or channels in the surface of the polypropylene resin film that wick – or pull – the moisture into it. By spreading the droplets out over a large surface area, the evaporation rate increases.

      “The wicking action of the film creates a self-drying surface that allows evaporation to happen in a natural way,” says Jim. “The combination of spreading and evaporation minimizes the release of hanging droplets as the humidity is decreased in the environment.”

    • Image of pipe. Side that does not have film has condensation. Coated side does not have drips.

      The film reduces the need to manually mop, which offers a labor-saving solution for food processing facilities. This helps increase productivity and cost savings while improving plant hygiene. 

      “Condensation is everywhere,” says Jim. “We think we can find other applications for this film, and we’re exploring those solutions. Meanwhile, it’s exciting to be able to contribute toward businesses’ sanitary practices and improved productivity.”