A team of Rice researchers has won first place in the Sustainable Technologies category of the SAE Media Group's Create the Future Design Contest with a protein-based coating that can prolong the shelf life of perishable foods.
The coating is a nanocomposite made from inexpensive or waste biomaterials, and can be applied to fruits and vegetables. Team members describe it as possessing “a combination of properties that satisfy multiple preservation requirements such as material flexibility, edibility, washability, effectiveness, biodegradability and appearance.”
The coating is comprised largely of egg-white protein, cellulose nanocrystals from wood pulp and such biocompatible modifiers as curcumin, glycerol and egg yolk. Curcumin strengthens the antimicrobial and antioxidant properties, thus reducing microbial growth, and egg yolk permits the optimal exchange of gases in the microenvironment to maintain the freshness of foods. The cellulose nanocrystals further reduce penetration by water and gases. The substance can be applied as a spray or by dip-coating.
The team is headed by Muhammad M. Rahman, assistant research professor of materials science and nanongineering (MSNE), and Pulickel M. Ajayan, the Benjamin M. and Mary Greenwood Anderson Professor of Engineering and chair of MSNE. Other members are Neethu Pottackal, a second-year graduate student in MSNE; Seohui “Sylvia” Jung, who earned her B.S. in MSNE at Rice last spring and now works as a product design engineer with Apple; and Yufei “Nancy” Cui, who earned her B.S. in bioengineering and is a Ph.D. student at MIT.
Finalists were selected by senior editors at SAE Media Group, producer of the contest, and judged by an independent panel of design engineers.