New film may double shelf life of perishable products

THIS may not be the first time you’ve heard of chitosan as material for packaging. A polymer made from the shells of shrimp and other crustaceans, it is a natural and biodegradable alternative to petroleum by-products used in conventional packaging.  Aside from its eco-friendly feature, chitosan film is nontoxic and has antimicrobial and antifungal properties. But further research is needed on how to produce such packaging.

Recently, researchers from the National University of Singapore (NUS) said they have developed a material made of natural chitosan-based composite film fortified with grapefruit seed extract (GFSE), an antioxidant that also has strong antiseptic, germicidal, anti-bacterial, fungicidal and anti-viral properties. This pairing can enhance shelf life of perishables such as bread.

In addition, the film has a mechanical strength and flexibility that are comparable to synthetic polyethylene film commonly used for food packaging. The composite film also effectively blocks ultraviolet light, hence slowing down the degradation of food products as a result of oxidation and photochemical deterioration reactions.

Ms Tan Yi Min (left) and Associate Prof Thian Eng San will continue to explore other possibilities stemming from their new product (Photo: National University of Singapore )

The product which took three years in the making was developed by Associate Professor Thian Eng San and PhD student Ms Tan Yi Min from the Department of Mechanical Engineering at NUS Faculty of Engineering.  With support from the A*STAR Singapore Institute of Manufacturing and Technology (SIMTech) and the Food Innovation & Resource Centre (FIRC), they will continue to conduct studies on how to improve the technology, specifically on the degradability of chitosan-based GFSE films. They plan to conduct an accelerated shelf life study to examine the extent of microbial growth and quality changes during storage of various food products, as well as explore opportunities to commercialize the composite film as a packaging material.