Production of methylcellulose films functionalized with poly-ε-caprolactone nanocapsules entrapped ß-carotene for food packaging application.

Nowadays, there is a worldwide demand in the production of innovative packaging that release active compounds to increase the shelf life of perishable food products. Therefore, this study produced methylcellulose films functionalized with poly-ε-caprolactone nanocapsules entrapped ß-carotene. The nanoparticles were produced by the nanoprecipitation method, and 10, 30, and 50 % of nanoparticles colloidal solution was added in the methylcellulose filmogenic solution. The films were characterized by the mechanical, physicochemical properties, antioxidant activity, and release of ß-carotene from the polymeric matrix to a food simulant. The results demonstrated satisfactory mechanical properties; however, the addition of nanoparticles decreased the Young's Modulus and increased the elongation at break. Regarding light transmission, the incorporation of ß-carotene nanoparticles promoted a decrease in the percentage of ultraviolet ray's transmittance through the film matrix, as well as visible light. The incorporation of nanoparticles improved the antioxidant activity of the films, which was proportional to the concentration of ß-carotene used in the formulation. The release of ß-carotene reached a maximum value of 10.93 µg g-1 film containing 70 % nanoparticles, which was a desired profile for food application. Finally, the methylcellulose films functionalized with poly-ε-caprolactone nanocapsules can release ß-carotene, and therefore, can be considered as a novel nanomaterial for food conservation, with a potential to increase the shelf life of perishable food products.

New Antioxidant Active Packaging Films Based on Yeast Cell Wall and Naphtho-γ-Pyrone Extract.

The main objective of this work is the development of new active films based on yeast cell wall obtained by high-pressure homogenization (YCW-H) supplemented with naphtho-γ-pyrone (CL-NGP) extract, which is a bioactive compound produced by Aspergillus tubingensis G131 with great antioxidant potential. A complete characterization of the functional properties of the bioactive films, such as their structural, colour, thermal, mechanical, hydration and water vapour transport, was carried out to evaluate the influence of the addition of the antioxidant compounds. Likewise, the antioxidant capacity of the developed materials and the specific migration of NGPs in food simulants were evaluated. The results showed that CL-NGP extract possessed an important antioxidant activity, which was maintained after incorporation in YCW-H films. The addition of 2 and 5% CL-NGPs decreased the hydration of films and consequently improved the water vapour barrier properties. It was observed that CL-NGPs migrate in fatty food simulants and retain their antioxidant capacity in the simulant. The results obtained in this work showed that bioactive films based on yeast cell walls with the addition of CL-NGPs have the potential to be used as packaging material in systems of interest in the food industry.

Physicochemical, Mechanical, and Structural Properties of Bio-Active Films Based on Biological-Chemical Chitosan, a Novel Ramon (Brosimum alicastrum) Starch, and Quercetin.

The properties of biological-chemical chitosan (BCh) films from marine-industrial waste and a non-conventional Ramon starch (RS) (Brosimum alicastrum) were investigated. Blended films of BCh/RS were prepared to a volume ratio of 4:1 and 1:4, named (BChRS-80+q, biological-chemical chitosan 80% v/v and Ramon starch, BChRS-20+q, biological-chemical chitosan 20% v/v and Ramon starch, both with quercetin), Films from commercial chitosan (CCh) and corn starch (CS), alone or blended (CChCS-80+q, commercial chitosan 80% v/v and corn starch, CChCS-20+q commercial chitosan 20% v/v and corn starch, both with quercetin) were also prepared for comparison purposes. Films were investigated for their physicochemical characteristics such as thickness, moisture, swelling, water-vapor permeability, and water solubility. In addition, their mechanical and structural properties were studied using Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric analysis (TGA) and Scanning Electron Microscopy (SEM) techniques. Antioxidant activity was evaluated as radical scavenging, and antimicrobial effect was also determined. The BCh and RS films presented similar tensile strength values compared with commercial biopolymers. Only films with chitosan presented antioxidant and antimicrobial activity. The FTIR spectra confirmed the interactions between functional groups of the biopolymers. Although, BChRS-80+q and BChRS-20+q films exhibited poor mechanical performance compared to their commercial counterparts, they showed good thermal stability, and improved antioxidant and antimicrobial activity in the presence of quercetin. BChRS-80+q and BChRS-20+q films have promising applications due to their biological activity and mechanical properties, based on a novel material that has been underutilized (Ramon starch) that does not compete with materials for human feeding and may be used as a coating for food products.