Control of aroma transfer by biopolymer based materials

Abstract

Biopolymers such as proteins offer unique functional properties that can be used in the field of edible or biodegradable active packagings. Among the barrier properties of biopolymer based packaging, the knowledge of the aroma compound transfer is required (i) to control losses and sorption of aroma compounds which are important contributors to the sensory product quality (ii) or to emit desirable flavour from active packaging in a controlled way. Permeability of 2-heptanone in protein coated papers was investigated. It was demonstrated that coating by gluten or casein decreased the permeability of 2-heptanone and that coated papers had promising aroma barrier compared to other packaging materials such as sulphuric or paraffin papers or LDPE. The ability of biopolymer films to control aroma release was also demonstrated. An aroma compound (carvacrol) was incorporated in a gluten protein matrix, which showed adequate ability to maintain aroma compounds during film processing. The release of the aroma compound into the headspace was followed under accelerated conditions of temperature and relative humidity (30°C and 60% RH). It was shown that the release rate was not dependent on carvacrol amount. The gluten film delayed aroma compound emission into the headspace for more than a month.