УПРАВЛЕНИЕ ХОЛОДИЛЬНОЙ ЦЕПЬЮ ПРИ ПОСТАВКАХ МЯСА: «СТАРЫЕ» И НОВЫЕ СТРАТЕГИИ

Meat is a perishable product with a short shelf life and therefore short selling times. Therefore, cold chain management in meat supply is of utmost importance for the maintenance of quality and safety of meat/meat products. Raw meat/meat products are likely to support the growth of pathogenic microorganisms and/or spoilage bacteria, and should be kept at temperatures that do not result in a risk to health. The cold chain should not be interrupted at all times along the meat distribution chain. The complexity of global meat supply chain, with frequently long distribution chains associated with transportation of the product within one country, from one to another country and from one to another continent, makes the solutions for the chilling and freezing regimes, as well as monitoring of time-temperature profiles, very important for the overall success in delivery of product which will be accepted by consumer for its freshness and safety levels. From recently, there are several available options for control and management of the cold chain, such as chilled and frozen storage combinations, superchilling, ionizing radiation, biopreservation, high hydrostatic pressure (HHP), active packaging, wireless sensors, supported with the software-based cold chain database (CCD).Мясо это скоропортящийся продукт с коротким сроком годности и,  следовательно, с коротким сроком реализации. Поэтому, управление холодильной цепью при поставке имеет первостепенное значение для поддержания качества и безопасности мяса и мясных продуктов. Сырое мясо и мясные продукты могут поддерживать рост патогенных микроорганизмов или микроорганизмов, вызывающих порчу, и, таким образом, должны храниться при температурах, которые исключают возникновение риска здоровью. Холодильная цепь должна соблюдаться на всех этапах реализации. В связи со сложностью глобальной цепи поставок мяса и мясных продуктов, которая нередко бывает достаточно протяженной и связанной с транспортировкой продукта, как в внутри страны, так и при поставках из одной страны в другую, или c одного континента на другой, требуется необходимость соблюдать режимы охлаждения и замораживания, отслеживать время и температуру, чтобы потребитель был уверен в свежести данных продуктов и их безопасности. В настоящее время существует несколько доступных вариантов контроля и управления холодильной цепью, таких как комбинации хранения в охлажденном и замороженном виде, суперохлаждение, ионизирующее излучение, биоконсервация, высокое гидростатическое давление (HHP), активная упаковка, беспроводные датчики поддерживаемые компьютерной базой данных холодильной цепи (CCD)

Removal of PCR Error Products and Unincorporated Primers by Metal-Chelate Affinity Chromatography

Immobilized Metal Affinity Chromatography (IMAC) has been used for decades to purify proteins on the basis of amino acid content, especially surface-exposed histidines and “histidine tags” genetically added to recombinant proteins. We and others have extended the use of IMAC to purification of nucleic acids via interactions with the nucleotide bases, especially purines, of single-stranded RNA and DNA. We also have demonstrated the purification of plasmid DNA from contaminating genomic DNA by IMAC capture of selectively-denatured genomic DNA. Here we describe an efficient method of purifying PCR products by specifically removing error products, excess primers, and unincorporated dNTPs from PCR product mixtures using flow-through metal-chelate affinity adsorption. By flowing a PCR product mixture through a Cu2+-iminodiacetic acid (IDA) agarose spin column, 94–99% of the dNTPs and nearly all the primers can be removed. Many of the error products commonly formed by Taq polymerase also are removed. Sequencing of the IMAC-processed PCR product gave base-calling accuracy comparable to that obtained with a commercial PCR product purification method. The results show that IMAC matrices (specifically Cu2+-IDA agarose) can be used for the purification of PCR products. Due to the generality of the base-specific mechanism of adsorption, IMAC matrices may also be used in the purification of oligonucleotides, cDNA, mRNA and micro RNAs

COLD CHAIN MANAGEMENT IN MEAT SUPPLY: «OLD» AND NOVEL STRATEGIES

Meat is a perishable product with a short shelf life and therefore short selling times. Therefore, cold chain management in meat supply is of utmost importance for the maintenance of quality and safety of meat/meat products. Raw meat/meat products are likely to support the growth of pathogenic microorganisms and/or spoilage bacteria, and should be kept at temperatures that do not result in a risk to health. The cold chain should not be interrupted at all times along the meat distribution chain. The complexity of global meat supply chain, with frequently long distribution chains associated with transportation of the product within one country, from one to another country and from one to another continent, makes the solutions for the chilling and freezing regimes, as well as monitoring of time-temperature profiles, very important for the overall success in delivery of product which will be accepted by consumer for its freshness and safety levels. From recently, there are several available options for control and management of the cold chain, such as chilled and frozen storage combinations, superchilling, ionizing radiation, biopreservation, high hydrostatic pressure (HHP), active packaging, wireless sensors, supported with the software-based cold chain database (CCD)

Efficiency of commercial enzymatic preparations in grain hydrolysis for preparation of substrates for beer fermentation

The chemical composition of malt is of crucial importance for wort quality and together with conditions of fermentation process, they determine beer quality. Commercial enzymes preparations compensate enzymes naturally present in the malt. As substitutes for malt, originally made from malted barley, we used corn grits, rice and unmalted barley mixtures as adjunct for wort, and Ceremix and Termamil enzyme preparations (microbial origin). Wort quality was monitored by following parameters: filterability speed, a-amino-nitrogen, total sugars, and degree of saccharification. Beer quality is assessed, beside usual parameters, by presence and levels of highly volatile alcohol and esters, such as 3-methyl butanol, 1-propanol, phenyl ethanol and ethyl acetate that dictate flavour and taste of beer. Higher values of these substances were found in all samples of wort supplemented with enzymes, in comparison with those without adding of Termamyl and Ceremix. Although these preparations increase efficiency of saccarification process, their usage concomitantly with enzymes from malt leads to elevation of substances that negatively contribute to beer flavour and taste. Addition of these enzyme preparations meets requests for good beer quality wherever enzymes from malt are not present in sufficient quantity. For optimal results 0.5% of Termamyl and Ceremix should be added, while in all other cases where malted substance is present with at least 50%, their usage should be strictly controlled

Fast photoluminescence quenching in thin films of 4,4 '-bis(2,2-diphenylvinyl)-1,1 '-biphenyl exposed to air

The photoluminescence (PL) quenching mechanism of UV light and air-exposed amorphous thin films of 4,4'-bis(2,2-diphenylvinyl)-1,1'-biphenyl (DPVBi), a well-known hole-transport material used in organic light-emitting diodes, is studied. Thin films of DPVBi are stable when exposed to UV light in vacuum but tend to degrade if oxygen is present simultaneously. This is evident from the changes in UV-vis absorption spectra of the latter, showing that degradation rate of DPVBi films is linearly proportional to both oxygen concentration and UV light intensity. Mass spectrometry study of such films revealed a number of different oxygen-containing molecules and fragments of DPVBi thus confirming apparent photo-oxidation process. Also, DFT study of molecular DPVBi with and without oxygen was carried out, the IR spectra calculated for the lowest energy molecules found and the results are compared with the experiment. The most sensitive to photo-oxidation is DPVBi photoluminescence, which decays exponentially with respect to the concentration of photo-oxidized DPVBi molecules (impurities). The PL quantum yield of DPVBi thin film drops to a half of its original value for 0.2% of the impurities present, at which point an average distance between DPVBi molecules (the donors) and photo-oxidized DPVBi species (acceptors) is an order of magnitude larger than the separation between two adjacent molecules. This implies a need for a long-range Forster energy transfer, which we rule out based on the lack of a donor-acceptor spectral overlap. The apparent discrepancy can be removed by postulating exciton self-diffusion in DPVBi thin films, for which there is supporting evidence in existing literature

Applications of computer vision systems for meat safety assurance in abattoirs: A systematic review

Introduction in 2017–2019 of the new EU legislation on official controls in food production allowed use of computer vision systems (CVSs) as complementary tools in meat inspection of bovines, pigs and poultry. A systematic literature review was performed to identify and analyse relevant articles reporting on the performances of CVSs used in abattoirs for ante- and post-mortem veterinary inspection and meat safety assurance, including systems for detecting carcass/organ contamination and lesions. In this review, 62 articles were identified and analysed. There were 35 articles reporting on CVS performance in the detection of carcass/organ lesions and 27 in the detection of carcass contamination. CVSs for broiler chicken, pig and bovine meat safety assurance were reported in 53, 5 and 4 articles, respectively. Not all developed CVSs were validated, and only three articles reported results from real-time evaluation of CVS performance in an abattoir vs performance of the official veterinarian. Most of the reported CVS performance measures (i.e., sensitivity and specificity) were >80%. A high specificity in detecting lesions and carcass contamination (i.e., a low number of false positives) is of importance for the food business operator in order to minimise food waste, whereas a high sensitivity (i.e., a low number of false negatives) is required for production of wholesome and safe meat. At present, the existing CVSs developed for overall meat safety assurance of broiler chicken carcasses and organs demonstrate very high sensitivities but suboptimal specificities, indicating the need for further CVS development and optimisation