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1.
Nature ; 629(8014): 1041-1046, 2024 May.
Article in English | MEDLINE | ID: mdl-38720078

ABSTRACT

Electrocaloric1,2 and electrostrictive3,4 effects concurrently exist in dielectric materials. Combining these two effects could achieve the lightweight, compact localized thermal management that is promised by electrocaloric refrigeration5. Despite a handful of numerical models and schematic presentations6,7, current electrocaloric refrigerators still rely on external accessories to drive the working bodies8-10 and hence result in a low device-level cooling power density and coefficient of performance (COP). Here we report an electrocaloric thin-film device that uses the electro-thermomechanical synergy provided by polymeric ferroelectrics. Under one-time a.c. electric stimulation, the device is thermally and mechanically cycled by the working body itself, resulting in an external-driver-free, self-cycling, soft refrigerator. The prototype offers a directly measured cooling power density of 6.5 W g-1 and a peak COP exceeding 58 under a zero temperature span. Being merely a 30-µm-thick polymer film, the device achieved a COP close to 24 under a 4 K temperature span in an open ambient environment (32% thermodynamic efficiency). Compared with passive cooling, the thin-film refrigerator could immediately induce an additional 17.5 K temperature drop against an electronic chip. The soft, polymeric refrigerator can sense, actuate and pump heat to provide automatic localized thermal management.


Subject(s)
Polymers , Refrigeration , Thermodynamics , Refrigeration/instrumentation , Polymers/chemistry , Cold Temperature , Electricity , Equipment Design , Electric Stimulation , Temperature
2.
Nature ; 631(8021): 544-548, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39020036

ABSTRACT

A long-standing challenge is how to formulate proteins and vaccines to retain function during storage and transport and to remove the burdens of cold-chain management. Any solution must be practical to use, with the protein being released or applied using clinically relevant triggers. Advanced biologic therapies are distributed cold, using substantial energy, limiting equitable distribution in low-resource countries and placing responsibility on the user for correct storage and handling. Cold-chain management is the best solution at present for protein transport but requires substantial infrastructure and energy. For example, in research laboratories, a single freezer at -80 °C consumes as much energy per day as a small household1. Of biological (protein or cell) therapies and all vaccines, 75% require cold-chain management; the cost of cold-chain management in clinical trials has increased by about 20% since 2015, reflecting this complexity. Bespoke formulations and excipients are now required, with trehalose2, sucrose or polymers3 widely used, which stabilize proteins by replacing surface water molecules and thereby make denaturation thermodynamically less likely; this has enabled both freeze-dried proteins and frozen proteins. For example, the human papilloma virus vaccine requires aluminium salt adjuvants to function, but these render it unstable against freeze-thaw4, leading to a very complex and expensive supply chain. Other ideas involve ensilication5 and chemical modification of proteins6. In short, protein stabilization is a challenge with no universal solution7,8. Here we designed a stiff hydrogel that stabilizes proteins against thermal denaturation even at 50 °C, and that can, unlike present technologies, deliver pure, excipient-free protein by mechanically releasing it from a syringe. Macromolecules can be loaded at up to 10 wt% without affecting the mechanism of release. This unique stabilization and excipient-free release synergy offers a practical, scalable and versatile solution to enable the low-cost, cold-chain-free and equitable delivery of therapies worldwide.


Subject(s)
Drug Storage , Hydrogels , Protein Denaturation , Protein Stability , Proteins , Syringes , Humans , Excipients , Freeze Drying , Hydrogels/chemistry , Proteins/administration & dosage , Proteins/chemistry , Proteins/economics , Trehalose , Freezing , Refrigeration , Papillomavirus Vaccines/chemistry , Drug Storage/economics , Drug Storage/methods
4.
BMC Vet Res ; 20(1): 410, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39267023

ABSTRACT

BACKGROUND: Different organic and inorganic bedding materials can be used in dairy farms. Among organic materials, there is an increasing interest in alternative substrates based on recycled manure solids (RMS). Microbiological analyses are crucial to monitor the microbial load and evaluate the presence of pathogens impacting animal welfare and health. However, logistic factors may hamper the possibility of immediately sending fresh samples to the laboratory, requiring storage in cooled conditions before analysis. METHODS: We assessed the impact of sample refrigeration and freezing of different organic and inorganic bedding substrates including separated raw manure solids (SRMS), anaerobically digested manure solids (ADMS), and new sand (NS), on the total bacterial count (TBC) and on different microbial classes. RESULTS: The TBC was higher in fresh NS and ADMS than in refrigerated and frozen samples of the same substrates; in addition, the TBC of ADMS was higher in refrigerated than frozen samples. The TBC of SRMS did not change significantly with refrigeration and freezing. Freezing reduced the total Gram-negative bacterial count more than refrigeration in all substrates. In fresh NS, Gram-negatives were higher than in both refrigerated and frozen NS. Escherichia coli counts were significantly lower in frozen than in refrigerated SRMS. However, both refrigeration and freezing of ADMS resulted in no E. coli growth. The coliform counts were also lower in frozen than refrigerated NS and SRMS. Frozen NS and ADMS showed lower counts compared to refrigeration for Gram-negative bacteria other than E. coli and coliforms. On the other hand, cold storage did not significantly impact the streptococci and streptococcus-like organisms (SSLO) count of all evaluated bedding substrates. CONCLUSION: Refrigeration and freezing affect the bacteriological results of bedding substrates, with freezing generally leading to lower counts than refrigeration. Whenever possible, preference should be given to analyzing fresh bedding samples, however, when necessary, refrigeration would be recommended over freezing, while acknowledging that the measured bacterial load might underestimate the actual microbial content.


Subject(s)
Bacterial Load , Dairying , Freezing , Manure , Refrigeration , Animals , Cattle , Manure/microbiology , Female , Housing, Animal , Bacteria/isolation & purification , Bacteria/classification
5.
Food Microbiol ; 123: 104595, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39038899

ABSTRACT

Listeria monocytogenes (Lm) is a pathogenic bacteria able to grow at refrigerated temperatures, widely distributed in the environment. This bacteria is susceptible to contaminate various food products of which refrigerated ready-to-eat foods (RTEF) may pose a risk for public health. In Europe, food business operators (FBOs) shall ensure that foodstuffs comply with the relevant microbiological criteria set out in the Regulation (EC) N°2073/2005. Food safety criteria for Lm are defined in RTEF throughout their shelf-life. FBOs should implement studies to demonstrate that the concentration of Lm does not exceed 100 CFU/g at the end of the shelf-life, taking into account foreseeable conditions of distributions, storage and use, including the use by consumers. However, this last part of the cold chain for food products is the most difficult to capture and control. For this purpose, the European Union Reference Laboratory for Lm (EURL Lm) launched an inquiry to its National Reference Laboratory network and reviewed the scientific literature from 2002 to 2020. The outcomes were integrated in the technical guidance document of the EURL Lm to assess shelf-life of RTEF which resulted in the recommendation to use 10 °C as the reference temperature to simulate the reasonably foreseen storage conditions in domestic refrigerators.


Subject(s)
Food Microbiology , Food Storage , Listeria monocytogenes , Refrigeration , Listeria monocytogenes/growth & development , Listeria monocytogenes/isolation & purification , Europe , Fast Foods/microbiology , Food Contamination/analysis , Food Safety , Temperature , Humans , Consumer Product Safety , Cold Temperature , European Union
6.
Food Microbiol ; 122: 104559, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38839223

ABSTRACT

Listeria monocytogenes is a concerning foodborne pathogen incriminated in soft cheese and meat-related outbreaks, highlighting the significance of applying alternative techniques to control its growth in food. In the current study, eco-friendly zinc oxide nanoparticles (ZnO-NPs) were synthesized using Rosmarinus officinalis, Punica granatum, and Origanum marjoram extracts individually. The antimicrobial efficacy of the prepared ZnO-NPs against L. monocytogenes was assessed using the agar well diffusion technique. Data indicated that ZnO-NPs prepared using Origanum marjoram were the most effective; therefore, they were used for the preparation of gelatin-based bionanocomposite coatings. Furthermore, the antimicrobial efficacy of the prepared gelatin-based bionanocomposite coatings containing eco-friendly ZnO-NPs was evaluated against L. monocytogenes in Talaga cheese (an Egyptian soft cheese) and camel meat during refrigerated storage at 4 ± 1 oC. Talaga cheese and camel meat were inoculated with L. monocytogenes, then coated with gelatin (G), gelatin with ZnO-NPs 1% (G/ZnO-NPs 1%), and gelatin with ZnO-NPs 2% (G/ZnO-NPs 2%). Microbiological examination showed that the G/ZnO-NPs 2% coating reduced L. monocytogenes count in the coated Talaga cheese and camel meat by 2.76 ± 0.19 and 2.36 ± 0.51 log CFU/g, respectively, by the end of the storage period. Moreover, G/ZnO-NPs coatings controlled pH changes, reduced water losses, and improved the sensory characteristics of Talaga cheese and camel meat, thereby extending their shelf life. The obtained results from this study indicate that the application of gelatin/ZnO-NPs 2% bionanocomposite coating could be used in the food industry to control L. monocytogenes growth, improve quality, and extend the shelf life of Talaga cheese and camel meat.


Subject(s)
Camelus , Cheese , Food Storage , Gelatin , Listeria monocytogenes , Nanocomposites , Zinc Oxide , Listeria monocytogenes/drug effects , Listeria monocytogenes/growth & development , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Cheese/microbiology , Gelatin/chemistry , Gelatin/pharmacology , Animals , Nanocomposites/chemistry , Food Preservation/methods , Meat/microbiology , Food Microbiology , Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Pomegranate/chemistry , Food Contamination/prevention & control , Food Contamination/analysis , Rosmarinus/chemistry , Refrigeration , Plant Extracts/pharmacology , Plant Extracts/chemistry
7.
J Dairy Sci ; 107(2): 1164-1174, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37709026

ABSTRACT

Milk extracellular vesicles (EV) have gained extensive attention as promising diagnostic and therapeutic tools. Pre-analytical raw milk storage at low temperatures is an ordinary and usually necessary step after sample collection. It is known that direct freezing of unprocessed whole milk contaminates the native pool of milk EV with other cell structures. However, less evidence is available regarding prolonged cooling at 4°C. The current study assessed whether pre-analytical storage of bovine raw milk for several days affected EV isolation and further analysis. To confirm the independence from the health status of the mammary gland, we analyzed milk samples stored at 4°C for 1, 2, 3, and 7 d past collection, respectively, from 2 quarters of the same cow with different somatic cell counts (SCC). Seven days of refrigeration did not change the milk EV size, concentration, or morphology. We did not detect any changes in the EV cargo regarding the amount of protein and RNA, nor in the specific EV markers TSG101, CD9, and CD81 in milk from quarters with high and low SCC. Overall, we observed fewer CD81 and CD9 markers in quarters with high SCC. Moreover, we found no reduction in the mastitis-related miRNA bta-miR-223-3p, suggesting that refrigeration for several days up to 1 wk is a possible storage option compatible with further EV analyses. The findings of this study enhance the confidence that milk EV are highly stable in the raw milk matrix.


Subject(s)
Cattle Diseases , Extracellular Vesicles , Mastitis, Bovine , Female , Cattle , Animals , Milk/chemistry , Cell Count/veterinary , Freezing , Refrigeration/veterinary , Extracellular Vesicles/metabolism , Mastitis, Bovine/metabolism
8.
J Sci Food Agric ; 104(14): 8748-8755, 2024 Nov.
Article in English | MEDLINE | ID: mdl-38940514

ABSTRACT

BACKGROUND: Glasswort represents a novel alternative to KCl for replacing sodium in meat products. To evaluate the effects of Na reduction on the quality changes of a traditional dry cured belly due to storage, fresh bellies were dry-salted with 2% NaCl (BCON), with 2% of a mixture containing 50% NaCl and 50% KCl (BKCl) or with 1% of a mixture of 90% NaCl and 10% powdered glasswort (BGW), dry-cured, sliced, vacuum packaged and stored under refrigeration for 60 days. RESULTS: The BKCl and BGW bellies were lower in sodium by one-third to one-half compared to BCON (with 1.6 g Na/100 g). Neither BKCl, nor BGW significantly differed from BCON in free fatty acids (FFA) before and after storage, whereas BGW showed almost twice as much 2-methylbutanal content as BCON. All bellies showed microbiological stability during storage. Micrococcaceae was the most abundant microbial group with values of 105 to 106 colony-forming units g-1. The BGW presented higher Micrococcaceae counts (approximately one log unit) but lower microbial biodiversity than BCON. CONCLUSION: The two alternative dry salting methods reduced the sodium content in bellies, at the same time as ensuring chemical and microbiological stability during refrigerated vacuum storage. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Subject(s)
Food Preservation , Food Storage , Meat Products , Potassium Chloride , Refrigeration , Animals , Potassium Chloride/chemistry , Meat Products/analysis , Meat Products/microbiology , Swine , Food Preservation/methods , Food Preservation/instrumentation , Sodium Chloride/analysis , Sodium Chloride/chemistry , Artemisia/chemistry
9.
J Sci Food Agric ; 104(12): 7688-7703, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38924063

ABSTRACT

BACKGROUND: Although microorganisms are the main cause of spoilage in prepared beef steaks, very few deep spoilage mechanisms have been reported so far. Aiming to unravel the mechanisms during 12 days of storage at 4 °C affecting the quality of prepared beef steak, the present study investigated the changes in microbial dynamic community using a combined high-throughput sequencing combined and bioinformatics. In addition, gas chromatography-mass spectrometry combined with multivariate statistical analysis was utilized to identify marker candidates for prepared steaks. Furthermore, cloud platform analysis was applied to determine prepared beef steak spoilage, including the relationship between microbiological and physicochemical indicators and volatile compounds. RESULTS: The results showed that the dominant groups of Pseudomonas, Brochothrix thermosphacta, Lactobacillus and Lactococcus caused the spoilage of prepared beef steak, which are strongly associated with significant changes in physicochemical properties and volatile organic compounds (furan-2-pentyl-, pentanal, 1-octanol, 1-nonanol and dimethyl sulfide). Metabolic pathways were proposed, among which lipid metabolism and amino acid metabolism were most abundant. CONCLUSION: The present study is helpful with respect to further understanding the relationship between spoilage microorganisms and the quality of prepared beef steak, and provides a reference for investigating the spoilage mechanism of dominant spoilage bacteria and how to extend the shelf life of meat products. © 2024 Society of Chemical Industry.


Subject(s)
Bacteria , Computational Biology , Volatile Organic Compounds , Cattle , Animals , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/metabolism , Volatile Organic Compounds/analysis , Bacteria/genetics , Bacteria/classification , Bacteria/isolation & purification , Bacteria/metabolism , Gas Chromatography-Mass Spectrometry , Food Microbiology , Food Storage , Pseudomonas/growth & development , Pseudomonas/metabolism , Lactobacillus/metabolism , Refrigeration , Brochothrix/metabolism , Brochothrix/growth & development , Brochothrix/isolation & purification , Lactococcus , Red Meat/microbiology , Red Meat/analysis
10.
Br Poult Sci ; 65(3): 287-296, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38466394

ABSTRACT

1. This study investigated the relationships of quality indices with the severity of wooden breast (WB) myopathy in chicken breast meat under refrigerated storage. The physicochemical properties, water-holding capacity (WHC), microbial quality and fatty acid profiles of normal chicken breast meat samples (NOR samples, n = 63), moderate WB (MWB, n = 63) myopathy and severe WB (SWB, n = 63) myopathy (MWB and SWB samples, respectively) were evaluated immediately after sampling and after 4 and 8 d of refrigerated storage at 4°C.2. Total collagen, fat, saturated and monounsaturated fatty acid contents, redness and pH of the SWB and MWB samples were higher than the NOR samples. The SWB samples that were stored for 8 d had poor WHC, total viable counts (TVC) of higher than 7.0log colony-forming units, total volatile basic nitrogen (TVB-N) content of greater than 15 mg/100 g and a thiobarbituric acid - reactive substance level of higher than 1 mg/kg malondialdehyde.3. No significant difference was observed in the TVB-N content and TVC of the MWB and NOR samples during storage. Polyunsaturated fatty acid content was lower in the SWB and MWB samples than in the NOR samples. The SWB samples were tougher than the MWB and NOR samples after 8 d of refrigeration.4. In conclusion, the quality of chicken breast meat with SWB myopathy degraded considerably over time; thus, such meat should not be subjected to extended refrigeration for storage.


Subject(s)
Chickens , Food Storage , Meat , Muscular Diseases , Pectoralis Muscles , Poultry Diseases , Refrigeration , Animals , Meat/analysis , Muscular Diseases/veterinary , Muscular Diseases/pathology , Pectoralis Muscles/chemistry , Pectoralis Muscles/pathology , Poultry Diseases/microbiology , Poultry Diseases/pathology , Fatty Acids/analysis
11.
BMC Oral Health ; 24(1): 1174, 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39363215

ABSTRACT

BACKGROUND: The pre-polymerization temperature of resin composite restorative materials could influence their adaptation to cavity details. As a current debate is existing about the refrigeration of resin composite restorative materials, this study was designed to assess the effect of refrigeration of 3 types of resin composite restorative materials with different matrix systems on their marginal adaptation in Class II restorations. METHODS: Forty-two sound maxillary molars, each with two separated Class II cavities, were used in this study. The teeth were assigned into 3 main groups (n = 14) according to the restorative /adhesive system used; an Ormocer-based composite (Admira Fusion/Futurabond M+, Voco GmbH, Cuxhaven, Germany), a methacrylate modified Ormocer-based (Ceram.X SphereTEC One/Prime&Bond Universal, Dentsply Sirona GmbH Konstanz, Germany), and a methacrylate-based (Tetric N-Ceram/Tetric N-Bond Universal, Ivoclar Vivadent AG, Schaan, Liechtenstein). Each group was then divided into 2 subgroups (n = 14) according to the gingival margin location; 1 mm above and 1 mm below the cemento-enamel junction (C.E.J). Each subgroup was further divided into 2 categories (n = 7) according to the storage temperature; stored at room temperature or stored in refrigerator at 4°- 5° C. Epoxy resin replicas were observed under scanning electron microscope (SEM) to examine the marginal gaps. A gab scoring system was used to assess the marginal adaptation of each restoration by giving scores on the basis of measurements of the maximum marginal gaps. The data obtained were statistically analyzed using the Chi-square test at a significance level of p < 0.05. RESULTS: None of the tested groups exhibited 100% gap-free margins irrespective of margin location or storage temperature. For both storage temperatures, no statistically significant difference was observed among all tested groups either with margins located above or below C.E.J (p > 0.05). As well, there was no statistically significant difference when comparing both marginal locations for each material (p > 0.05). Regarding the effect of storage temperature, statistically significant difference was only observed between the room-temperature stored groups with margins located above C.E.J and their corresponding groups stored in refrigerator (p < 0.05). CONCLUSION: The refrigeration of resin composite restorative materials prior to the restorative procedures revealed a deleterious effect on marginal adaptation of the restorations with margins located in enamel regardless the type of material used.


Subject(s)
Composite Resins , Dental Marginal Adaptation , Dental Restoration, Permanent , Composite Resins/chemistry , Humans , Refrigeration , Materials Testing , Dental Cavity Preparation/classification , Organically Modified Ceramics , Dental Materials/chemistry , Microscopy, Electron, Scanning , Molar , Polymethacrylic Acids/chemistry , Methacrylates , Siloxanes
12.
J Korean Med Sci ; 38(43): e338, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37935165

ABSTRACT

BACKGROUND: Here we investigated whether cold chain workers' insomnia, work-related stress, and viral anxiety contributed to their depression. Furthermore, we investigated the role of viral anxiety in mediating the association between work-related stress and depressive symptoms. METHODS: All 200 invited cold chain workers voluntarily responded to an online survey. All were working at a market in Taiyuan, Shanxi Province, China, and responsible for testing nucleic acids in imported cold chain foods and disinfecting outer packaging at government request. We collected their demographic variables and rated their symptoms using the Stress and Anxiety to Viral Epidemics-6 Items (SAVE-6), Patient Health Questionnaire-9, Insomnia Severity Index (ISI), Perceived Stress Scale (PSS), and Maslach Burnout Inventory - General Survey (MBI-GS). RESULTS: Cold chain workers' depression was significantly correlated with higher SAVE-6 (r = 0.450, P < 0.01), ISI (r = 0.603, P < 0.01), MBI-GS (r = 0.481, P < 0.01), and PSS (r = 0.390, P < 0.01) scores. SAVE-6 score was significantly correlated with ISI (r = 0.462, P < 0.01), MBI-GS (r = 0.305, P < 0.01), and PSS (r = 0.268, P < 0.01) scores. Linear regression revealed that their depression was predicted by SAVE-6 (ß = 0.183, P = 0.003), ISI (ß = 0.409, P < 0.001), and MBI-GS (ß = 0.236, P = 0.002, adjusted R² = 0.440, F = 40.04, P < 0.001) scores. Mediation analysis showed that their burnout directly influenced their depression, while viral anxiety or insomnia severity mediated the influence of burnout on depression. CONCLUSION: The study showed that burnout was a direct cause of depression and that viral anxiety and insomnia severity mediated the relationship between burnout and depression.


Subject(s)
Burnout, Professional , COVID-19 , Sleep Initiation and Maintenance Disorders , Humans , COVID-19/epidemiology , Sleep Initiation and Maintenance Disorders/epidemiology , Depression/epidemiology , Depression/etiology , Pandemics , Refrigeration , Anxiety/epidemiology , Anxiety/etiology , Surveys and Questionnaires
13.
An Acad Bras Cienc ; 95(suppl 1): e20220578, 2023.
Article in English | MEDLINE | ID: mdl-37255170

ABSTRACT

The influence of refrigeration on the post-embryonic development of Chrysomya putoria larvae was evaluated, regarding its resistance in the logistics of storage and distribution in biotherapy. Previously sterilized larvae were submitted to four periods of storage under refrigeration (T1=12 h, T2=24 h, T3=48 h and T4=72 h) and control (without sterilization and refrigeration). Newly hatched larvae (0.200 g) were stored between 3 and 9ºC. After refrigeration, 40 neo-larvae (in triplicate) were transferred to 50 g of protein diet and incubated in an acclimatized chamber. There was a significant difference in the larval body mass (T1 and T2) and in the duration of larval, pupal and total development (T3 and T4). The sex ratios found in the four treatments did not differ from what was expected. Normality rates were 100% for all treatments. There was no significant difference between the Control, T1 and T2 treatments for larval, pupal and total viability. There was a significant difference between control (C) and T4 (larval viability), between C, T3 and T4 (pupa) and between C and T4 (total). C. putoria has resistance under refrigeration and storage of up to 56 h, presenting viability above 70% for use in biotherapy.


Subject(s)
Diptera , Animals , Calliphoridae , Refrigeration , Larva , Biological Therapy , Pupa
14.
J Dairy Res ; 90(2): 191-199, 2023 May.
Article in English | MEDLINE | ID: mdl-37326234

ABSTRACT

We evaluated the possibility of increasing the storage temperature of raw milk for Provolone Valpadana cheesemaking, to identify the most suitable conditions of time and temperature for a pre-maturation process. We used Principal Component Analysis (PCA) to analyze the overall effects of different storage conditions on chemical, nutritional and technological characteristics of the raw milk. Four different thermal storage cycles, two at fixed temperature/time (6 and 12°C for 60 h) and two with two-phase thermal cycle (10 and 12°C for 15 h, followed by refrigeration at 4°C for 45 h) were studied. Although a moderate heterogeneity among raw milks from the 11 producers of Provolone Valpadana cheese was observed, PCA revealed the critical aspects of the extreme storage conditions (60 h of refrigeration). Some samples resulted in anomalous behaviors, probably related to unexpected fermentation phenomena occurring with increasing storage temperature. The acidification and the increase in the contents of lactic acid, soluble calcium, and degree of retinol isomerization observed in the anomalous samples can compromise the technological functionality of milk. Conversely, the storage with a two-phase thermal cycle did not lead to variations in any measured characteristic, suggesting that mild refrigeration conditions (10 or 12°C for 15 h followed by 4°C for 45 h) could be a good compromise in favoring milk pre-maturation without altering its quality characteristics.


Subject(s)
Milk , Refrigeration , Animals , Temperature , Milk/chemistry , Refrigeration/veterinary
15.
Gesundheitswesen ; 85(10): 857-870, 2023 Oct.
Article in German | MEDLINE | ID: mdl-37793411

ABSTRACT

BACKGROUND: Breaches in the cooling chain with exposure of vaccines to temperatures outside the target range of +2°C to +8°C may reduce their efficacy and impair immune responses. Following the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach, this review assesses the quality and content of international clinical practice guidelines on vaccine management. The results were used to derive recommendations for the vaccine management in ambulatory care in Germany. METHODS: Based on a systematic search and screening process with predefined criteria, the selected guidelines were rated by three reviewers using the AGREE II domains: scope and purpose, stake-holder involvement, rigor of development, clarity of presentation, applicability, and editorial independence. The content of the guidelines was retrieved and summarized according to five predefined categories: cold chain, responsibilities, equipment, storage, and monitoring. The review was registered in PROSPERO (CRD42021270524). RESULTS: A total of nine clinical practice guidelines were selected for evaluation. The sum score of the documents varied between 17% to 89% of the maximum possible score. All guidelines included recommendations in the five content categories but differed in detail. The key recommendations were: a) continuous cold chain required; b)≥2 trained, responsible staff members; c) storage in original wrappings; d) appropriate, preferably purpose-built refrigerator with two-point thermometer or data logger; e) routinely implemented monitoring processes including daily temperature recording. A public monitoring system was recommended in some guidelines. CONCLUSION: Our systematic review identified key information for vaccine storage and management to support the future development of German recommendations for vaccine storage.


Subject(s)
Vaccination , Vaccines , Humans , Germany , Vaccines/therapeutic use , Refrigeration , Ambulatory Care
16.
Molecules ; 28(4)2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36838928

ABSTRACT

In the current research, the binary solution containing ionic liquid (IL), 1-ethyl-1-methylmorpholinium dimethyl phosphate ([C1C2MOR][DMP]), 1-ethyl-1-methylpiperidinium dimethyl phosphate ([C1C2PIP][DMP]), or N,N,N-triethyl-N-methylammonium dimethyl phosphate ([N1,2,2,2][DMP]) with ethanol are investigated as new working fluids for absorption refrigeration technology. The IL was mixed with ethanol, which was considered as a refrigerant. Experimental (vapor + liquid) phase equilibria (VLE) of these binary systems were measured by an ebulliometric method within a temperature range from T = (328.15 to 348.15) K with an increment of 10 K and pressures up to 90 kPa. Experimental VLE data were correlated using non-random two-liquid (NRTL) within the maximum average relative deviation of 0.45%, which confirms the effectiveness of using such a model for calculations. Each of the proposed binary systems exhibit a negative deviation from Raoult's law, which is a very important characteristic for working pairs used in absorption heat pumps or absorption refrigerators. From a technological point of view, measurements of physicochemical properties play an important role. In this research, liquid density and dynamic viscosity were determined at temperatures from T = (293.15 to 338.15) K at ambient pressure over the whole concentration range. These properties were correlated using empirical equations. From experimental density data, the excess molar volumes were determined and correlated using the Redlich-Kister type equation. Ionic liquid: [C1C2MOR][DMP] and [C1C2PIP][DMP] were synthesized and characterized using NMR analysis. The thermophysical characterization of pure ILs, including glass transition temperature (Tg) and heat capacity at the glass transition temperature (ΔgCp), was determined using the differential scanning calorimetry technique (DSC) at atmospheric pressure. In this work, the combination of basic studies on the effect of the cation structure of an ionic liquid on the properties of their solutions with ethanol and the possibility of future application of the tested systems in a viable refrigeration system are presented.


Subject(s)
Ionic Liquids , Ionic Liquids/chemistry , Refrigeration , Thermodynamics , Technology , Ethanol
17.
BMC Microbiol ; 22(1): 34, 2022 01 25.
Article in English | MEDLINE | ID: mdl-35078415

ABSTRACT

BACKGROUND: As the increased consumption of ready-to-eat meat alternatives is a fairly recent trend, little is known about the composition and dynamics of the microbiota present on such products. Such information is nonetheless valuable in view of spoilage and food safety prevention. Even though refrigeration and modified-atmosphere-packaging (MAP) can extend the shelf-life period, microbial spoilage can still occur in these products. In the present study, the microbiota of a vegetarian alternative to poultry-based charcuterie was investigated during storage, contrasting the use of a culture-dependent method to a culture-independent metagenetic method. RESULTS: The former revealed that lactic acid bacteria (LAB) were the most abundant microbial group, specifically at the end of the shelf-life period, whereby Latilactobacillus sakei was the most abundant species. Metabarcoding analysis, in contrast, revealed that DNA of Xanthomonas was most prominently present, which likely was an artifact due to the presence of xanthan gum as an ingredient, followed by Streptococcus and Weissella. CONCLUSIONS: Taken together, these results indicated that Lb. sakei was likely the most prominent specific spoilage organisms (SSO) and, additionally, that the use of metagenetic analysis needs to be interpreted with care in this specific type of product. In order to improve the performance of metagenetics in food samples with a high DNA matrix but a low bacterial DNA load, selective depletion techniques for matrix DNA could be explored.


Subject(s)
Bacteria/growth & development , DNA Barcoding, Taxonomic/methods , DNA Barcoding, Taxonomic/standards , Food Microbiology/methods , Food Storage/standards , Meat Products/microbiology , Vegetarians , Atmosphere , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Colony Count, Microbial , DNA Barcoding, Taxonomic/statistics & numerical data , Food Microbiology/standards , Food Packaging/methods , Food Packaging/standards , Food Storage/methods , Food Storage/statistics & numerical data , Meat Products/classification , RNA, Ribosomal, 16S/genetics , Refrigeration
18.
Phys Rev Lett ; 129(17): 178001, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36332249

ABSTRACT

We present the operational principle for a refrigerator that uses inertial effects in active Brownian particles to locally reduce their (kinetic) temperature by 2 orders of magnitude below the environmental temperature. This principle exploits the peculiar but so-far unknown shape of the phase diagram of inertial active Brownian particles to initiate motility-induced phase separation in the targeted cooling regime only. Remarkably, active refrigerators operate without requiring isolating walls opening the route toward using them to systematically absorb and trap, e.g., toxic substances from the environment.


Subject(s)
Cold Temperature , Refrigeration , Temperature
19.
Transfusion ; 62(9): 1736-1742, 2022 09.
Article in English | MEDLINE | ID: mdl-35919959

ABSTRACT

BACKGROUND: Platelets for transfusion have a storage time of 5-7 days at 22°C-24°C, which results in a strain on the supply chain and supply shortages. We describe a novel method to extend platelet storage using xenon (Xe) gas under high pressure and refrigeration. STUDY DESIGN AND METHODS: Apheresis platelets (APU) prepared in 65% platelet additive solution (PAS) were stored under standard conditions (SC) at 20°C-24°C to Day 5. Paired APUs were prepared with Xe and stored to Day 14 at 2°C-6°C under hyperbaric conditions (XHC). A standard panel of in vitro assays was conducted. RESULTS: XHC platelets were viable out to Day 14. The average pH of Day 14 platelets was 6.58, and 86% maintained some degree of swirl compared with 7.02 and 100% swirl for Day 5 SC platelets. The rate of glycolysis was reduced under XHC storage with less glucose consumption and lactate generation. Activation levels for Day 14 platelets, while increased, did not prevent response to agonists in vitro, including epinephrine + Adenosine 5-Diphosphate (EPI/ADP) and thrombin receptor-activating peptide (TRAP) aggregation. Thromboelastogram (TEG) assessment showed 80% or greater conservation of platelet function for Day 14 xenon stored platelets compared with Day 5 SC platelets. DISCUSSION: Platelet storage with the Xe/hyperbaric/cold method is a feasible candidate for extension of storage to 14 days based on in vitro characteristics. In vivo recovery and survival studies are indicated. The capability to extend platelet storage to 14 days would make large strides toward resolving issues of platelet outdating for prophylactic use.


Subject(s)
Blood Platelets , Blood Preservation , Adenosine Diphosphate , Blood Platelets/physiology , Blood Preservation/methods , Humans , Platelet Function Tests , Refrigeration , Xenon/pharmacology
20.
Biologicals ; 78: 27-35, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35803876

ABSTRACT

Possible applicability of controlled temperature chain (CTC) for selected antisera and vaccines was evaluated. Bivalent oral polio vaccine (OPV), hepatitis B vaccine (HepB vaccine; monovalent and combined) and antisera (lyophilized and liquid scorpion-antivenom and liquid snake-antivenom) were tested. Samples were stored at accelerated (35 ± 5 °C) and freezing (-25 ± 5 °C) conditions for 24 h, one week and one month in addition to recommended storage condition (2-8 °C), except OPV samples that were tested at accelerated and refrigerated (2-8 °C) conditions compared to recommended storage conditions (-25 ± 5 °C). All samples were tested for potency. Protein content and composition were determined for antisera samples. All vaccine vial-monitors were evaluated. HepB vaccine was subjected to aluminum-content assay, shake test and microscopical examination. No significant change in antisera potency was detectable under accelerated condition for a week. OPV stored in refrigerator for a month and at accelerated condition for 48 h maintained acceptable potency. Monovalent and combined HepB vaccine maintained acceptable potency under accelerated condition for a month and a week, respectively. Freezing adversely affected HepB vaccine. In conclusion, reevaluation of storage conditions of tested products is urgently required; this can reduce storage costs and improves their availability. Other products should be tested for possible CTC applicability.


Subject(s)
Hepatitis B Vaccines , Poliomyelitis , Antivenins , Drug Storage , Humans , Phenylbutyrates , Poliomyelitis/prevention & control , Poliovirus Vaccine, Oral , Refrigeration , Temperature
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