It's not a pretty sight, when good broccoli goes bad.
But a California company, Apio Inc., has developed a coated membrane technology to keep broccoli fresh longer. ``If you get the right atmosphere, you can get produce to last a long time,'' said Ray Clarke, principle scientist at Apio.
Clarke and other speakers addressed developments in ``intelligent packaging'' during a May 9 new technology forum at SPE-Antec, the Society of Plastics Engineers' conference in Charlotte.
Each type of food has its own specific shelf-life demands. For example, different types of produce have a different ``respiration rate''-the need to ``breath'' through the package.
Broccoli is a challenge to keep fresh. Clarke said that Apio is based in Guadalupe, Calif., in the center of the state's broccoli-growing region, for that reason.
``Fresh produce is a living, respiring organism,'' Clarke said.
Apio's solution is called BreatheWay, made by coating a substrate using polymer chemistry. The result is a highly permeable, ``breathable'' section on the package that allows the produce to breathe. ``We can simply dial-in the amount of oxygen that we want,'' Clarke said.
Before turning to broccoli, Clarke spent five years working on packaging for bananas. Apio technology is being used to extend the shelf life of Chiquita bananas, he said.
Apio is part of Landec Corp. of Menlo Park, Calif.
Kay Cooksey, a professor at Clemson University, said advances in nanotechnology, coating or barrier layers and a new process known as ``smart blending'' make it possible to create very targeted packaging. Smart blending can put the barrier structure directly into the plastic material in blends that are ``mechanically interlocked,'' Cooksey said.
Some intelligent packaging is already on store shelves. Cooksey cited anti-theft tags, ripeness indicators and packages that indicate food has reached the correct serving temperature.
Spoilage indicators - used now mainly for food distribution, not point-of-sale - uses inks that change color to show quality and spoilage, she said. The spoilage indicators are embedded in the adhesive of a label on products such as meat and fish.
Cooksey also discussed work on anti-microbial packaging at Clemson's Center for Flexible Packaging at the university in Clemson, S.C. Because some antimicrobials are expensive, one solution could be to blend two of them together, including one with a lower price, she said. The additives can keep foods from spoiling.
Another speaker, William Spano of CSP Technologies Inc., described the company's technology to create interconnected channels through a solid polymer structure - creating pathways for substances to pass through. That leads to packaging specifically tailored to absorb or release things like moisture, odors, oxygen and carbon dioxide.
CSP, based in Auburn, Ala., has more than 100 patents in the technology.
Spano said that because the additive is in the polymer itself, the materials can be used in any manufacturing process.