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Six gelatin films incorporating different ratios of sage oil (SO) and hemp oil (HO) were subjected to contact with food simulants and environmental exposure, respectively, for 3 months, at 15 000 lx light intensity, 40°C and 65% relative humidity. The migration and degradation, respectively, of the antioxidants into the simulants as well as their loss in the environment were mathematically modelled. The fastest release rate of antioxidants was noticed in the case of SO : HO 0 : 2 in 85% ethanol while the highest degradation rates were achieved after 18 days in the case of SO : HO 0 : 2 in water and 3% acetic acid and after 22 days in 85% ethanol. The antioxidants from SO : HO 0 : 2 were lost to the largest extent (5.37%) while those from SO : HO 1 : 1 to the lowest extent (3.49%). SO : HO 1 : 1 was selected as the most efficient film, by optimizing the amount of antioxidants available solely for food protection with the longest stability in the simulants. From industrial point of view, the mathematical modelling of the previously mentioned processes allows for the selection of the most effective film from a group with comparable physical–chemical–microbiological properties. Copyright © 2016 John Wiley & Sons, Ltd.

This study was carried out to assess the shelf life and microbiological safety of wheat bread during storage in a packaging system made of Ag/TiO2 nanocomposite (Ag/TiO2-P) in comparison with bread packed in high density polyethylene (HDP-P) and bread not subject to packaging (CS). The Ag/TiO2 nanocomposite was prepared by sol–gel procedure, and its morphostructural characterization was performed by X-ray diffraction, Fourier transform infrared spectroscopy and transmission electron microscopy. The Ag/TiO2-P was prepared via inclusion of nanocomposite between the polyethylene layers to avoid bread–nanocomposite contact. Chemical and microbial stability of bread expressed in terms of total fat, protein, sugar, lipid hydroperoxides and yeasts, moulds, and Bacillus subtilis and Bacillus cereus counts, respectively, was monitored for 6 days. Experimental data indicate that Ag/TiO2-P considerably extends the shelf life and microbiological safety of bread in comparison with HDP-P and CS. A possible mechanism involved in the preservation of the bread is hypothesized. Copyright © 2014 John Wiley & Sons, Ltd.

Orange juice was stored in polyethylene packages containing Ag-TiO2-Fe or TiO2 composites to establish the extent to which these composites influence the physical-chemical, microbiological and organoleptic characteristics of the juice. The composites were characterized in terms of structure (X-ray diffraction, transmission electron microscopy, Fourier-transformed infrared) and photoactivity while the packages were profiled in terms of their UV-vis absorption and water vapor permeability. The acidity and the browning rate of the sample stored in the package with Ag-TiO2-Fe decreased after 10 days of storage, as compared with the sample deposited in TiO2 packages and with the reference sample (polyethylene). The microbial population in the orange juice increased after 10 days of storage in all packages, but the increase was smaller in the Ag-TiO2-Fe polyethylene package. The organoleptic properties of the fresh orange juice deposited in package with Ag-TiO2-Fe were almost identical with those of the freshly prepared sample (0 days), whereas those of the juice deposited in the reference package were unacceptable. Practical Applications The study provides evidence that the packages of polyethylene modified with Ag-TiO2-Fe can be used to store fresh orange juice for 10 days at room temperature (22.5C).

composites havebeen characterized using X-ray diffraction, Raman and FTIR spectroscopy techniques and TEM microscopy. The role of zeo-lite particles in the photoreduction process was demonstrated by using different kinetic models. The apparent constant ratefor photoreduction increases in direct proportion with the content of zeolite and is higher for the composites modified withFe than for those modified with Ag nanoparticles. The results demonstrate that composites have a higher photocatalytic

Summary The chemical changes of three types of cheese, yoghurt and kefir were evaluated during storage in packages containing TiO2 with two different compositions of the mixed anatase–rutile phase. The influence of TiO2 packaging during storage on titratable acidity and fat content and on the external aspect was investigated. Fourier Transformed Infrared Spectroscopy (FTIR) analyses were performed to establish whether the TiO2 penetrated the food during storage. The results showed that the TiO2 nanoparticles deposited on polyethylene surface significantly decreased acidity and fat content of the investigated cheese and yoghurt types. During storage in TiO2 nanopackages, the change in chemical parameters is accentuated as the content of rutile grows from 2.8% to 6.9%. The sensory evaluation revealed that the dairy products stored for 11 days in TiO2 nanopackages present similar colour, texture and flavour with that of the references; the samples stored in polyethylene film were found to be unacceptable.