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The increase in the polymer-based materials needs has induced along the waste accumulation, thus argued higher interest in recycling. The study aims to assess the structural, morphological, mechanical resistance, physical–chemical and biochemical characteristics, as well as the preservative role during the curd cheese storage of a recycled polylactic acid (PLA)-based film modified with Ag-graphene-TiO2 nanostructured composite, obtained by recovering the composite from the used film, followed by its incorporation in new PLA. The breaking load of the recycled film was 24% lower than that of the new film and 10% higher than of the neat PLA. Differential scanning calorimetry (DSC) showed changes of the recycled PLA's surface tension and crystallization degree in a greater extent than in the newly prepared film, revealing better incorporation of the recovered composite into the PLA matrix. Fourier transformed infrared spectroscopy showed the formation of C–O–Ti bridges between composite and PLA both in new and recycled film. Oxygen transmission rate (OTR) of the new and recycled film decreased by 33% and 45%, respectively, in comparison with reference PLA. The curd cheese was successfully stored in the recycled packaging; the organoleptic characteristics of cheese wrapped in recycled film were superior in comparison with the new film. The variation of fat and protein contents and mass loss was the lowest when the recycled film was used as packaging material. The study successfully showed the possibility to recover and recycle the used PLA-based films modified with inorganic nanocomposites. [ABSTRACT FROM AUTHOR]

The chemical changes of homemade curd cheese were evaluated during storage in unmodified and modified packages with extract of garlic (Allium sativum) and thyme (Satureja hortensis), during 3 and 6 day, at room temperature. White paper and low density polyethylene have been used as packaging materials. The influence of type packaging during storage on titrated acidity, chloride, protein and dry weight content was investigated. Also, a set of measurements was performed on cheese stored at room temperature without being packed, after being treated with thyme or garlic extract by immersion for 10 minutes in the extract. The basic compounds from thyme extract and the antioxidant compounds from garlic extract influence the physico-chemical parameters of curd cheese. [ABSTRACT FROM AUTHOR]

The study aims to establish if the packages based on paper or LDPE modified with extract of thyme and garlic are efficient in preserving the summer salame during storage, as compared with the unmodified packages. Eight different types of packages based on paper or LDPE impregnated in the aqueous extracts of thyme and garlic were prepared and used to test their preservation activity during the storage of the summer salame, a Romanian meat product, at room temperature and light. The eight types of packages are as follows: product impregnated in extract of thyme (IP thyme) and garlic (IP garlic), summer salame packaged in unmodified paper (H) and LDPE (LDPE), summer salame packaged in paper impregnated in extract of thyme (IH thyme) and in extract of garlic (IH garlic), summer salame packaged in LDPE impregnated in extract of thyme (ILDPE thyme) and in extract of garlic (ILDPE garlic). At 0, 3 and 6 days, the following physico-chemical parameters were monitored during storage: acidity, pH, water, salt and protein content. Additionally, the changes of the organoleptic characteristics were established. It was observed that the most reduced decrease of the acidity and protein content during storage occured in the summer salame impregnated in the thyme extract and in the salame packaged in the paper impregnated in the garlic extract. Moreover, the organoleptic characteristics of the samples impregnated in the thyme and garlic extract, excepting those in packages based on LDPE were not significantly changed during storage, at room temperature and under light. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]