Unexpected possible consequences of plastic packaging reuse

Reusable packaging is considered among the measures for achieving plastic waste reduction goals, however, some unexpected issues may arise with a shift from single-use to a reuse model for plastic packaging for industrial food applications, involving the hygienic and sensory spheres. Considerations are based on the diffusional properties of polymers leading to contamination with chemicals and to aroma scalping; the degradative effects of aging, of mechanical stress due to multiple use, and of the repeated sanitization with aggressive chemicals; the proneness of plastic surfaces to microbial film colonization. The reuse of plastic packages has the potential to increase the level of chemical contamination and of microplastic particles in foods, and could reduce product hygienic and sensory quality and standardization

Quality maintenance performance and resistance to Tribolium castaneum and Plodia interpunctella penetration of an alternative packaging material for semolina

Insect attacks to food packages are a major concern for food producers, who are often blamed for being responsible for the occurrence of contamination which seriously affects the image of the company. Wheat semolina is commonly packed in paper bags, which do not always offer sufficient protection against insect pests. The present research evaluated the performance of a new packaging alternative, consisting of paper laminated with polypropylene (P+CPP), in terms of resistance to penetration by two common cereal product pests, namely Tribolium castaneum and Plodia interpunctella, and quality maintenance of the packaged product. Neither of the two pest species tested were able to pierce the P+CPP, while no differences were observed in the time required to penetrate other materials. Moreover, quality parameters, namely pH, acidity and color, did not differ significantly among samples packed in different materials. The new P+CPP combination is a promising alternative for the packaging of semolina, because it offers improved protection against pests compared with conventional materials, while maintaining the paper appearance of traditional packaging

Exploring the effects of hyperbaric storage on the optical, structural, mechanical and diffusional properties of food packaging materials

The effect of hyperbaric storage (HS) on food packaging materials was evaluated. PA/PE, PP/EVOH/PE, PET and PLA pouches filled with hydroethanolic simulant (D1) were stored at 0.1 and 200 MPa for up to 35 days and analyzed for optical, structural, mechanical and diffusional properties. HS weakened PLA seals, which easily failed after 7 days releasing the simulant. Both PET and PLA films swelled during HS, reducing PET physical ageing and PLA crystallinity. These structural effects caused PET and PLA mechanical properties to vary during HS, and a slight WVTR increase in PLA. Optical, structural and mechanical properties of multi-material films did not change upon HS. Nevertheless, both PA/PE and PP/EVOH/PE released critical amounts of adhesives after 7 and 35 days under pressure, respectively. Results indicate the critical role of the packaging material of foods intended for HS, and the need for its careful selection in future studies on the topic

Evaluation of Variability in the Sweet Orange Germplasm through Next Generation Clonal Fingerprinting

The great phenotypic variability characterizing the sweet orange [Citrus sinensis(L.) Osbeck] germplasm arises from spontaneous bud mutations, causing a diversification into major groups (common, Navel and blood oranges). A huge divergence also occurred within each varietal group. The genetic basis of such variability, also including nutritional and qualitative traits (ripening time, colour, fruit shape, acidity, sugars), is currently uncharacterized, and therefore not exploitable. With the aim of describing the somatic mutation events in the sweet orange group a deep-sequencing of 20 Italian and foreign accessions was performed by Illumina platform, allowing the identification of single nucleotide polymorphisms (SNPs), structural variants (SVs) and large deletions, specific to each varietal group or clone-specific. A subset of SNPs used for the design of two 384 SNP - GoldenGate Assays allowed to genotype 225 CREA sweet orange accessions. The developed markers represent the first reliable molecular tools able to unambiguously fingerprint each somatic mutant. Moreover, they might be used to associate mutations with phenotypic traits, and are a powerful tool for traceability. By using the GoldenGate assay, we have been able to fingerprint several blood orange clones starting from DNAs isolated from leaves or juice. These tools will potentially provide the consumer with a guarantee on the quality and origin of juices, avoiding eventual frauds

Aloe vera extract as a promising treatment for the quality maintenance of minimally-processed table grapes

The effect of an edible film obtained from a commercial Aloe vera extract, on the quality maintenance of minimally processed grapes belonging to three different cultivars (Sugar One, Victoria and Black Magic) was evaluated by enzymatic (PPO, PME, β-GAL), physicochemical (pH, acidity, °Brix), and sensorial methods. All the analyzed parameters were measured in extracts obtained from minimally processed grapes packaged in ordinary atmosphere and stored at 4 °C for 15 days. Samples dipped into Aloe vera showed significant differences (p≤0.05) compared to untreated ones. The determination of such parameters and the evaluation of consumer acceptability were helpful to determine the effectiveness of the post-harvest treatment with Aloe vera for a storage period of 15 days. © 2015, Sociedade Brasileira de Ciencia e Tecnologia de Alimentos, SBCTA. All rights reserved

Shelf Life Extension and Nutritional Quality Preservation of Sour Cherries through High Pressure Processing

The present study assessed the effectiveness of high pressure processing (HPP) for the quality maintenance of pitted sour cherries, with special regard to microbial stabilization and the maintenance of color and of chemical–nutritional properties. The HPP treatment (600 MPa for 3 min at 4 °C) was effective at minimizing the initial microbial load, which remained at negligible levels throughout 5 months of refrigerated storage. The color and total phytochemical content of sour cherries were not influenced by the HPP treatment and were maintained at levels comparable with the fresh product for 3 months of refrigerated storage. For longer storage periods, the typical red color decreased, in agreement with the content of total anthocyanins, which showed a significant decrease (up to 65% after 5 months). The antioxidant activity, measured by the ABTS and DPPH assays, was not affected by the HPP treatment, but slightly reduced during refrigerated storage. The study suggests that HPP may be exploited to extend the shelf life, while maintaining the fresh-like features of sour cherries, thus offering an alternative option to current preservation techniques (based on freezing or heating) commonly applied to this product

Influence of Saccharomyces uvarum on volatile acidity, aromatic sensory profile of Malvasia delle Lipari wine

The present study investigated chemical and sensory properties of Malvasia delle Lipari DOC (Denomination of Controlled Origin) wine fermented with a cryotolerant strain of Saccharomyces uvarum, characterized by low levels of acetic acid production. In particular, experimental wine was tested for volatile acidity and for aromatic profile by gas-chromatography and the results were compared with the same wine produced with a commercial strain of Saccharomyces cerevisiae. Sensory analysis was carried out to assess the identification of experimental wine as Malvasia delle Lipari by defining its sensory profile. Fermentation with S. uvarum gave a final product with lower volatile acidity, lower alcohol content and higher total acidity. Moreover, differences in the aroma profile could be ascribed to different characteristics of the yeasts. Concerning sensorial analysis, the panel assigned higher scores in positive attributes to the wine fermented with S. uvarum

Fermi-surface transformation across the pseudogap critical point of the cuprate superconductor La1.6−x_{1.6-x}Nd0.4_{0.4}Srx_{x}CuO4_4

The electrical resistivity $\rho$ and Hall coefficient R$_H$ of the tetragonal single-layer cuprate Nd-LSCO were measured in magnetic fields up to $H = 37.5$ T, large enough to access the normal state at $T \to 0$, for closely spaced dopings $p$ across the pseudogap critical point at $p^\star = 0.235$. Below $p^\star$, both coefficients exhibit an upturn at low temperature, which gets more pronounced with decreasing $p$. Taken together, these upturns show that the normal-state carrier density $n$ at $T = 0$ drops upon entering the pseudogap phase. Quantitatively, it goes from $n = 1 + p$ at $p = 0.24$ to $n = p$ at $p = 0.20$. By contrast, the mobility does not change appreciably, as revealed by the magneto-resistance. The transition has a width in doping and some internal structure, whereby R$_H$ responds more slowly than $\rho$ to the opening of the pseudogap. We attribute this difference to a Fermi surface that supports both hole-like and electron-like carriers in the interval $0.2 < p < p^\star$, with compensating contributions to R$_H$. Our data are in excellent agreement with recent high-field data on YBCO and LSCO. The quantitative consistency across three different cuprates shows that a drop in carrier density from $1 + p$ to $p$ is a universal signature of the pseudogap transition at $T=0$. We discuss the implication of these findings for the nature of the pseudogap phase.Comment: 11 pages, 12 figure

On the performance of a pilot hybrid constructed wetland for stormwater recovery in Mediterranean climate

Abstract The overall efficiency of a pilot-scale hybrid constructed wetland (H-CW), located on a retail store's parking area in Eastern Sicily, for alternative treatment of stormwater runoff and of sequential batch reactor (SBR) effluent was evaluated. Experimental activities were focused on system performances, including wastewater (WW) quality and hydraulic monitoring. System design, macrophyte growth and seasonal factors influenced the pilot plant performance. Very high removal efficiency for microbial indicators were reported within the subsurface horizontal flow unit (HF), playing a strategic role for Clostridium perfringens. The algal growth occurred in the free water surface (FWS) unit and inhibited removal efficiencies of total suspended solids (TSS), biochemical oxygen demand (BOD5) and chemical oxygen demand (COD), impairing water quality. The whole H-CW showed good efficiency in trace metals removal, especially for Pb, Zn, and Cu. Preliminary results suggested the reliability of the H-CW technology in decentralised water treatment facilities for enhancing water recovery and reuse

Transitions from the Quantum Hall State to the Anderson Insulator: Fa te of Delocalized States

Transitions between the quantum Hall state and the Anderson insulator are studied in a two dimensional tight binding model with a uniform magnetic field and a random potential. By the string (anyon) gauge, the weak magnetic field regime is explored numerically. The regime is closely related to the continuum model. The change of the Hall conductance and the trajectoy of the delocalized states are investigated by the topological arguments and the Thouless number study.Comment: 10 pages RevTeX, 14 postscript figure