As a result of environmental concern, there is an increasing interest in the development of biodegradable polymers for packaging with suitable properties, as an alternative to the synthetic petroleum-based polymers. However, such biodegradable polymers are prevented for use in wide industrial and commercial packaging, due to their limited gas and vapor barrier properties. This obstacle urges innovative strategies to achieve enhanced barrier properties, using “bio-layering” technologies. Whey Protein Isolate (WPI), a by-product of the cheese industry, has quite promising properties for packaging purposes. It possesses good oxygen, aroma, and oil barrier properties, but poor water vapor barrier properties. Modified WPI coatings for improved barrier were developed. Several WPI coatings were obtained, adding PVOH and pectin to improve the coated film properties and nanoclays were used to improve water vapor barrier properties. A reduction of about 90%, in the oxygen transmission rate (OTR) and about 27% in the water vapor permeability were obtained.
