1. Introduction
Nanotechnology is by definition the manipulation and utilisation of structures with at least one dimension in the nanometrelength (atomic, molecular, macromolecular) scale, which creates unique properties and functions for novel applications. Nanomaterials can occur naturally (e.g. in ashes, as soil particles or biomolecules), be produced unintentionally (e.g. in diesel exhaust) or be intentionally engineered (Tiede et al. 2008). Nano-food packaging is a new generation of packaging technology based on nanomaterials, which has become one of the most developed areas in nanotechnology and represents a radical alternative to the conventional food packaging. Fillers are entities incorporating into traditional packaging materials, mostly in low fractions, to improve the properties of the original material (Cushen, Kerry, Morris, CruzRomero, & Cummins, 2014). Reinforcement by engineered or natural nanomaterials as fillers, has appeared to be an interesting strategy for improving the functional properties of synthetic and biosourced materials. Two main approaches are used to produce nanomaterials. In the ‘‘top-down” approach, nanometric structures are obtained by size reduction of bulk materials, involving grinding,