a b s t r a c tIn order to provide gelatin films with antioxidant capacity, two sulphur-free water-insoluble lignin powders (L 1000 and L 2400 ) were blended with a commercial fish-skin gelatin from warm water species at a rate of 85% gelatin: 15% lignin (w/w) (GeL 1000 and GeL 2400 ), using a mixture of glycerol and sorbitol as plasticizers. The water soluble fractions of GeL 1000 and GeL 2400 films were 39.38 AE 1.73% and 46.52 AE 1.66% respectively, rendering radical scavenging capacity (2,2 0 -azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, ABTS assay)) of 27.82 AE 2.19 and 15.31 AE 0.88 mg vitamin C equivalents/g film, and ferric ion reducing ability (FRAP assay) of 258.97 AE 8.83 and 180.20 AE 5.71 mmol Fe 2þ equivalents/g film, respectively. Dynamic oscillatory test on film-forming solutions and Attenuated Total Reflectance (ATR)-FTIR spectroscopy study on films revealed strong lignin-induced protein conformational changes, producing a noticeable plasticizing effect on composite films, as deduced from the study of mechanical (traction and puncture tests) and thermal properties (Differential Scanning Calorimetry, DSC). The gelatin films lose their typical transparent and colourless appearance by blending with lignin; however, the resulting composite films gained in light barrier properties, which could be of interest in certain food applications for preventing ultraviolet-induced lipid oxidation. Lignin proved to be an efficient antioxidant at non-cytotoxic concentrations, however, no remarkable antimicrobial capacity was found.

: The effects of plasma protein (PP) and soy fiber (SF) content on the properties (binding properties, color, and texture) of bologna sausages as influenced by fat level (F) were assessed by response surface methodology (RSM). Higher soy fiber and plasma protein contents favored the formation of harder, chewier structures with improved fat and water binding properties. Fat reduction decreased textural properties and increased weight loss. Cooking loss was affected (P < 0.05) by interactions between PP and F and chewiness was affected (P < 0.05) by interactions between SF and F. Plasma protein influenced binding and textural properties more than soy fiber and was, therefore, thought best to limit the effect of fat reduction.

8 9 ** This centre has implemented and maintains a Quality Management System in 10 compliance with ISO standard 9001:2000. 11 12 ABSTRACT 13 With the purpose to improve the physico-chemical performance of plain gelatin 14 and chitosan films, compound gelatin-chitosan films were prepared. The effect 15 of the gelatin origin (commercial bovine-hide gelatin and laboratory-made tuna-16 skin gelatin) on the physico-chemical properties of films was studied. The 17 dynamic viscoelastic properties (elastic modulus G', viscous modulus, G'' and 18 phase angle) of the film forming solutions upon cooling and subsequent heating 19revealed that the interactions between gelatin and chitosan were stronger in the 20 blends made with tuna-skin gelatin than in the blends made with bovine-hide 21 gelatin. As a result, the fish gelatin-chitosan films were more water resistant 22 (~18% water solubility for tuna vs 30% for bovine) and more deformable (~68% 23 35

Nanocomposite materials obtained by TiO2 incorporation into ethylene–vinyl alcohol copolymers, extensively used in food packaging, are prepared via a straightforward melting process. The structural characteristics of the nanocomposites are examined using wide and small angle X‐ray scattering (WAXS/SAXS), and vibrational infrared and Raman spectroscopies. A microscopy (SEM/TEM) study shows that the materials obtained are highly homogeneous at the nanometric scale, exhibiting an intimate contact between both the organic and inorganic components. TiO2 incorporation into this polymer matrix renders self‐sterilized nanocomposite materials upon light excitation, which are tested against nine micro‐organisms (gram‐positive and gram‐negative bacteria, cocci, and yeasts) typically involved in food contamination and/or degradation. Overall, the nanocomposites display an impressive performance in the killing of all micro‐organisms with a maximum for an oxide content between 2–5 wt %. The measurement of the physico‐chemical properties together with the structural characterization of the materials provide conclusive evidence that the nanocomposites biocidal capability born of the nanometric organo‐inorganic interface and rationalize the existence of a maximum as a function of the TiO2 content.

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The effect of high-pressure processing on mechanical and thermal properties of four complex packaging materials (polyethylene/ethylene vinyl alcohol/ polyethylene: PE/EVOH/PE; metallized polyester/polyethylene: PETmet/PE; polyester/ polyethylene: PET/PE; polypropylene SiOx recovered: PPSiOx) was studied. Pouches of the different materials containing distilled water or olive oil as food simulants, as well as empty ones, were subjected to 400 MPa for 30 min, at temperatures of 20 or 60°C. Delamination and wrinkling were a general consequence of the high-pressure processing of multilayer polymeric systems. However, no signifi cant changes were observed regarding the mechanical properties of PE containing laminates after pressurization. PPSiOx underwent signifi cant modifi cations as SiOx completely broke down. Neither thermal property was affected by pressure, as it was the processing temperature that induced tempering effects on the crystallization behaviour of polymeric components. Only PE/EVOH/ PE, when in contact with water as a simulant, presented a decrease in the melting point temperature.

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