Utjecaj hlađenja na mikrobiološku kvalitetu površine svinjskih polovica i post mortalne procese u mesu svinja

The aim of the study was to observe the microclimatic conditions in chilling room and their influenceonpork temperature, pH value, amount of lactic acid, and microbiological quality of pig carcasses surface. During the experiment, the temperatures in chilling room and the temperatures of meat corresponded with valid food legislation. The values of relative humidity were in one third of measurements lower and in more than a half of measurements higher than limits prescribed. Higher values of relative humidity have adversely influencedthereductionof aerobic plate counts. In two cases, the non-standard post-mortal process (evaluated on the basis of pH value and the amount of lactic acid) was discovered.Cilj istraživanja je bilo praćenje mikroklimatskih uvjeta u prostoriji za hlađenje svinjetine i njihov utjecaj na temperaturu mesa, pH vrijednost, količinu mliječne kiseline kao i mikrobiološku kvalitetu površine svinjskih polovica. Tijekom pokusa temperature u prostoriji za hlađenje i temperature mesa bile su sukladne važećim propisima za hranu. Rezultati mjerenja relativne vlage su kod jedne trećine mjerenja pokazivali niže a kod više od polovine mjerenja više vrijednosti od propisanih. Više vrijednosti relativne vlage štetno su utjecale na smanjenje broja aerobnih bakterija. U dva je slučaja utvrđen nestandardni post mortalni proces (procijenjen na temelju pH vrijednosti i količine mliječne kiseline)

Electrically conductive electrospun polymeric mats for sensing dispersed vegetable oil impurities inwastewater

This paper addresses the preparation of electrically conductive electrospun mats on a base of styrene-isoprene-styrene copolymer (SIS) and multiwall carbon nanotubes (CNTs) and their application as active sensing elements for the detection of vegetable oil impurities dispersed within water. The most uniform mats without beads were prepared using tetrahydrofuran (THF)/ dimethyl formamide (DMF) 80:20 (v/v) as the solvent and 13 wt. % of SIS. The CNT content was 10 wt. %, which had the most pronounced changes in electrical resistivity upon sorption of the oil component. The sensors were prepared by deposition of the SIS/CNT layer onto gold electrodes through electrospinning and applied for sensing of oil dispersed in water for 50, 100, and 1000 ppm. - 2019 by the authors.This publication was supported by the Qatar University Collaborative Grant QUCG-CAM-19/20-2. The findings achieved herein are solely the responsibility of the authors. The publication of this article was funded by the Qatar National Library.Scopu

Preparation of progressive antibacterial LDPE surface via active biomolecule deposition approach

The use of polymers in all aspects of daily life is increasing considerably, so there is high demand for polymers with specific properties. Polymers with antibacterial properties are highly needed in the food and medical industries. Low-density polyethylene (LDPE) is widely used in various industries, especially in food packaging, because it has suitable mechanical and safety properties. Nevertheless, the hydrophobicity of its surface makes it vulnerable to microbial attack and culturing. To enhance antimicrobial activity, a progressive surface modification of LDPE using the antimicrobial agent grafting process was applied. LDPE was first exposed to nonthermal radio-frequency (RF) plasma treatment to activate its surface. This led to the creation of reactive species on the LDPE surface, resulting in the ability to graft antibacterial agents, such as ascorbic acid (ASA), commonly known as vitamin C. ASA is a well-known antioxidant that is used as a food preservative, is essential to biological systems, and is found to be reactive against a number of microorganisms and bacteria. The antimicrobial effect of grafted LDPE with ASA was tested against two strong kinds of bacteria, namely, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), with positive results. Surface analyses were performed thoroughly using contact angle measurements and peel tests to measure the wettability or surface free energy and adhesion properties after each modification step. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to analyze the surface morphology or topography changes of LDPE caused by plasma treatment and ASA grafting. Surface chemistry was studied by measuring the functional groups and elements introduced to the surface after plasma treatment and ASA grafting, using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). These results showed wettability, adhesion, and roughness changes in the LDPE surface after plasma treatment, as well as after ASA grafting. This is a positive indicator of the ability of ASA to be grafted onto polymeric materials using plasma pretreatment, resulting in enhanced antibacterial activity. - 2019 by the authors.Funding: This publication was made possible by Award JSREP07-022-3-010 and NPRP10-0205-170349 from the Qatar National Research Fund (a member of The Qatar Foundation). The statements made herein are solely the responsibility of the authors

Usporedba kakvoće strojno otkoštenog mesa peradi upotrebom različitih postupaka separacije

Selected parameters of quality (hydroxyproline, calcium, bone particles content, and histological determination of bone particles) of mechanically deboned poultry meat (MDPM - „firmseparation“ and soft separation „Baadermeat“) were compared. Comparison of results with composition (except bone particles) of fresh poultry meat (breast and thigh muscles) was performed. Hydroxyproline content was significantly different and the mean value of hydroxyproline content was in mechanically deboned meat more than two-fold higher in comparison with Baader meat (333.17 mg.100g-1, 152.90 mg.100g-1 respectively). Similar results were achieved in calcium content (1.94g.kg-1, 1.05 g.kg-1 respectively). The mean content of bone particles was 0.27 % (MDPM) and 0.034 % (Baader). Finally, histological determination of bone particles in MDPM and Baader meat was carried out.U radu su uspoređeni odabrani parametri kakvoće (hidroksiprolin, kalcij, sadržaj čestica kostiju i histološko određivanje čestica kostiju) strojno otkošteog mesa peradi (engl. mechanically deboned poultry meat; MDPM -„čvrsta separacija“ i „meka separacija“ „Baader meso“). Rezultati su uspoređeni sa sastavom (izuzev koštanih čestica) svje žeg pilećeg mesa (mišići prsiju i bataka). Sadržaj hidroksi prolina pokazivao je značajne razlike, a srednja vrijednost sadržaja hidroksiprolina u strojno otkoštenom mesu bila je dvostruko veća u odnosu na „Baader meso“ (333,17 mg.100g-1, odnosno 152,90 mg.100g-1). Analiza sadržaja kalcija dala je slične rezultate (1,94g.kg-1, odnosno 1,05 g.kg-1). Srednji sadržaj čestica kostiju iznosio je 0,27 % (MDPM) i 0,034 % („Baader“). Provedeno je histološko određivanje čestica kostiju u MDPM i „Baader“ mesu

On composite laminates with extensional anisotropy

The definite list of extensionally (membrane) anisotropic composite laminates with up to 21 plies is presented. The listings comprise of individual stacking sequences, which are characterized in terms of angle- and cross-ply sub-sequence relationships as well as the blend-ratio of unbalanced angle-plies. Dimensionless parameters, including lamination parameters, are provided, from which the extensional and bending stiffness terms are readily calculated and an assessment of the bending stiffness efficiency made for angle- and cross-ply sub-sequences. Comparisons are made between the structural response of extensionally-anisotropic laminates and laminates with both extensional- and bending-anisotropy; Initial- and post-buckling responses are considered at the panel level together with the static response of a complete wing-box structure

Zakonodavstvo Republike Slovačke vezano uz divljač i meso divljači

Basic legislative frame of breeding of game as farm animals is included in the Veterinary care law No. 488/2002 Z.z. with amendments, Food act No. 152/1995 Z.z. with amendments. Veterinary care law (488/2002 Z.z.) establishes veterinary requirements for live animals and also for products of animal origin, including animal products in relation to the public health protection. Government regulations were added to the Veterinary care law in the process of implementation of EU Directives into national legislation. Food act 152/1995 Z.z. establishes conditions of production of food and other animal products, their handling and placing on the market to support and protect consumers and their health, and the roles and organisation of food supervision and keeping of rules. Requirements for health safety, hygiene, composition and quality of food, ingredients, technological processes used in food production, packaging, marking, storage, transportation, handling and distribution, and also rules for sampling and sample analysis procedures are established in the Food code of the Slovak Republic.Osnovni zakonski okvir za uzgoj divljači na farmama uključen je u Zakon o veterinarskoj skrbi br. 488/2002 Z.z. s izmjenama, Zakon o hrani br. 152/1995 Z.z. s izmjenama. Zakon o veterinarskoj skrbi (488/2002 Z.z.) određuje veterinarske zahtjeve za žive životinje kao i za namirnice životinjskog porijekla, uključivši životinjske proizvode, a koji se odnose na zaštitu ljudskog zdravlja. U Zakon o veterinarskoj skrbi dodani su državni propisi u procesu primjene EU propisa u nacionalno zakonodavstvo. Zakon o hrani br. 152/1995 Z.z. određuje uvjete proizvodnje hrane i drugih životinjskih proizvoda, rukovanje s istima te stavljanje namirnica životinjskog porijekla na tržište u cilju potpore i zaštite potrošača i njihovog zdravlja, kao i ulogu i organizaciju zdravstvenog nadzora namirnica, te poštivanje propisa. Zakon o hrani Republike Slovačke određuje zahtjeve za zdravstvenu i higijensku ispravnost namirnica, njihov sastav i kakvoću, sastojke, tehnološke procese koji se primjenjuju u proizvodnji hrane, opremanje, označavanje, skladištenje, prijevoz, rukovanje i promet, kao i propise za uzorkovanje i postupke analize uzoraka

Biotechnological production process and life cycle assessment of graphene

The aim of this study is to compare the graphene produced using a biotechnological method (Escherichia coli) with the graphene produced by Hummers' method (a chemical method) and to study the effect on the energy consumption and environment. The results indicated that the chemical reduction process has higher energy consumption, approximately 1642 Wh, than the energy consumption of the biotechnological reduction process, which is 5 Wh. The potential of global warming (GWP 100) improved by 71% using the biotechnological route for the production of graphene. Abiotic depletion, the photochemical ozone creation potential, and marine aquatic ecotoxicity potential were improved when the biological route was employed, compared with the chemical route. The eutrophication potential, terrestrial ecotoxicity, and ozone depletion layer changed very little since the main variables involved in the production of graphene oxide and waste management are the same. The biotechnological method can be considered a green technique for the production of graphene, especially given the reduction in the negative effects on global warming, abiotic depletion, the photochemical ozone creation potential, and the marine aquatic ecotoxicity potential

Usporedba kakvoće strojno otkoštenog mesa peradi upotrebom različitih postupaka separacije

Selected parameters of quality (hydroxyproline, calcium, bone particles content, and histological determination of bone particles) of mechanically deboned poultry meat (MDPM - „firmseparation“ and soft separation „Baadermeat“) were compared. Comparison of results with composition (except bone particles) of fresh poultry meat (breast and thigh muscles) was performed. Hydroxyproline content was significantly different and the mean value of hydroxyproline content was in mechanically deboned meat more than two-fold higher in comparison with Baader meat (333.17 mg.100g-1, 152.90 mg.100g-1 respectively). Similar results were achieved in calcium content (1.94g.kg-1, 1.05 g.kg-1 respectively). The mean content of bone particles was 0.27 % (MDPM) and 0.034 % (Baader). Finally, histological determination of bone particles in MDPM and Baader meat was carried out.U radu su uspoređeni odabrani parametri kakvoće (hidroksiprolin, kalcij, sadržaj čestica kostiju i histološko određivanje čestica kostiju) strojno otkošteog mesa peradi (engl. mechanically deboned poultry meat; MDPM -„čvrsta separacija“ i „meka separacija“ „Baader meso“). Rezultati su uspoređeni sa sastavom (izuzev koštanih čestica) svje žeg pilećeg mesa (mišići prsiju i bataka). Sadržaj hidroksi prolina pokazivao je značajne razlike, a srednja vrijednost sadržaja hidroksiprolina u strojno otkoštenom mesu bila je dvostruko veća u odnosu na „Baader meso“ (333,17 mg.100g-1, odnosno 152,90 mg.100g-1). Analiza sadržaja kalcija dala je slične rezultate (1,94g.kg-1, odnosno 1,05 g.kg-1). Srednji sadržaj čestica kostiju iznosio je 0,27 % (MDPM) i 0,034 % („Baader“). Provedeno je histološko određivanje čestica kostiju u MDPM i „Baader“ mesu