Edible Polyelectrolyte Complex Nanocoating for Protection of Perishable Produce

Abstract

Approximately one-third of the food produced in the world is not consumed, largely due to spoilage. Fresh fruits and vegetables have a shelf life of only a few days. To reduce spoilage, packaging with a high oxygen barrier is needed, but plastic packaging also creates waste. In this study, edible polyelectrolyte complexes consisting of chitosan (CH) and pectin (PT) are deposited onto fresh fruit to extend shelf life. This unique edible coating imparts a high gas barrier and high transparency that can slow the ripening of bananas and browning of apple slices. A 1.5 μm thick CH/PT coating reduces the oxygen transmission rate of a 179 μm polyester film by >10-fold. This single-step deposition process uses only water-soluble, edible biopolymers and ambient conditions, which is promising for reducing both food and packaging waste.

Highly moisture resistant super gas barrier polyelectrolyte complex thin film

“…Flexible gas barrier coatings are widely used for various packaging applications to improve the shelf life of produce, reduce food waste, and protect flexible electronics 1–4 . The best commercial gas barrier systems, such as metalized plastic and metal oxide thin films, have unique drawbacks 5,6 .…”

“…Flexible gas barrier coatings are widely used for various packaging applications to improve the shelf life of produce, reduce food waste, and protect flexible electronics. [1][2][3][4] The best commercial gas barrier systems, such as metalized plastic and metal oxide thin films, have unique drawbacks. 5,6 Despite their high barrier, the lack of transparency and recyclability of metalized plastic, and the rigidity and poor adhesion of metal oxide films (e.g., SiO x and Al x O y ), severely limit their benefit.…”

Polyelectrolyte-multivalent molecule complexes: physicochemical properties and applications

“…205 The direct one-pot deposition of preformed PECs in aqueous solution 206 is an attractive approach to generate thin films in a single step. 204 Although the first studies focused on the formation of functional films using twopolyelectrolytes complexes as precursors, [207][208][209] in recent years, PEMMC components have been exploited too. Azzaroni and co-workers have developed a powerful and versatile substrateindependent self-assembly strategy for poly(allylamine)/phosphate aggregates that allows generating nanofilms by simply immersing the substrate in an aqueous solution containing PEMMCs (Fig.…”

Chitosan and Whey Protein Bio-Inks for 3D and 4D Printing Applications with Particular Focus on Food Industry

“…CS and carrageenan formed a polyelectrolyte complex gel [ 57 ], while the polyelectrolyte hydrogels have excellent performance in the 3D printing of soft actuators and robots [ 58 ]. Moreover, the nanocoated polyelectrolyte gel of CS and pectin was applied in fruit preservation as the outer membrane [ 59 ]. The presence of the coating can reduce oxidation and discoloration and can also delay the development of microorganisms to extend their shelf life [ 41 ].…”