The incorporation of nanoclays, micro and nanofibers of cellulose and carbon nanofibers and nanotubes into bioplastics is attracting a great deal of research interest regarding improvement of general physical properties in plastics and bioplastics. The present overview shows, beyond the reviewed state of the art, nanobiocomposites specifically developed for food packaging applications, in which mainly cellulose biofibers, their highly crystalline building nanoblocks and food contact complying non-MMT (non-montmorillonite) nanoclays have been used in melt blending and solution casting processing routes to improve the barrier properties to gases and vapours and to impart additional functionalities to biopackaging plastics. Bar rier properties are known to be very strong limiting factors for the current widespread application of, mainly, biopolyesters in self-life extension of biopackaged foods. The paper specifically exemplifies on novel functionalities by showing novel nanobiocomposite films of biopolyesters with enhanced gas, vapour and UV barrier and simultaneously exhibiting controlled release capacity of an antimicrobial and antioxidant natural plant extract of interest in active antimicrobial food biopackaging applications.