Search Results (51)

This investigation presents a rigorous comparative evaluation of methanolic and hexanoic extracts from Takhrai (Cymbopogon citratus) leaves against commercial antioxidants for mitigating oxidative stress in heat-stressed ruminants. Phytochemical profiling revealed significantly higher concentrations of bioactive compounds in methanolic extracts, particularly ascorbic acid (2.12 ± 0.08 mg/g), sinapic acid (0.71 ± 0.03 mg/g), and apigenin (0.38 ± 0.02 mg/g). Methanolic extracts demonstrated exceptional antioxidant activities (DPPH IC₅₀ = 36.62 ± 0.65 μg/mL), superior erythrocyte protection (hemoglobin oxidation IC₅₀ = 12.06 ± 0.29 μg/mL), and robust Nrf2 pathway activation (HO-1 induction = 3.42 ± 0.17-fold). Metabolomic analyses revealed preservation of glutathione metabolism and attenuation of lipid peroxidation product accumulation. Immunomodulatory assessment demonstrated significant reduction of pro-inflammatory cytokines (TNF-α reduced by 54.3 ± 4.8%) and enhancement of anti-inflammatory mediators following LPS challenge. While storage stability presented limitations at ambient conditions (52.4 ± 3.7% activity retention after 6 months), refrigeration substantially improved preservation (92.3 ± 2.8%). Comprehensive effectiveness ranking across twelve parameters positioned methanolic extracts (mean score 1.7) comparable to vitamin E (1.6) and superior to other interventions. Collectively, these findings establish methanolic Takhrai extracts as promising sustainable alternatives to commercial antioxidants, with particular relevance for ruminant production in tropical regions Full article

The cryogenic supercritical hydrogen storage system offers notable advantages including heightened hydrogen storage density and operation under relatively moderate conditions compared to conventional hydrogen storage methodologies. In this study, a cryogenic supercritical hydrogen storage system based on the multi-stage Joule–Brayton refrigeration cycle is presented, analyzed, and optimized. The proposed system employs a five-stage cascade cycle, each stage utilizes a distinct refrigerant, including propane, ethylene, methane, and hydrogen, facilitated by Joule–Brayton cycles, with expanders employed for mechanical work recovery, which is capable of effectively cooling hydrogen from ambient temperature and atmospheric pressure to a cryogenic supercritical state of −223.15 °C (50 K), 18,000 kPa, exhibiting a density of 73.46 kg/m³ and a hydrogen processing capacity of 2 kg_H2/s. The genetic algorithm is applied to optimize 25 key parameters in the system, encompassing temperature, pressure, and flow rate, with the objective function is specific energy consumption. Consequently, the specific energy consumption of the system is 5.71 kWh/kg_H2 with an exergy efficiency of 56.2%. Comprehensive energy analysis, heat transfer analysis, and exergy analysis are conducted based on the optimized system parameters, yielding insights crucial for the development of medium- and large-scale supercritical hydrogen storage systems. Full article

Cold chain temperature management is crucial for preserving product quality and safety across various industries. While Computational Fluid Dynamics (CFD) provides detailed insights into thermal analysis and fluid dynamics, its computational intensity limits practical applications. This study presents a novel hybrid approach combining CFD and machine learning to enhance both computational efficiency and prediction accuracy in cold storage temperature management. A validated 3D CFD model was developed to analyze temperature distribution and airflow patterns in a refrigerated container with multiple storage boxes. Taking advantage of the cold room’s symmetrical design along its longitudinal axis significantly reduced computational requirements while maintaining model accuracy. Over 200 cases were simulated by varying key process parameters to generate training data for machine learning models. Random Forest (RF) and Neural Network (NN) models were developed and compared, with RF demonstrating consistently superior performance across all storage locations. Feature importance analysis revealed cold air temperature as the dominant control variable, while SHAP analysis identified optimal operational ranges for air velocity and heat transfer coefficients that balance product quality with energy efficiency. This research work also revealed distinct patterns in the influence of process parameters, with cold air and ambient temperatures showing hierarchical impacts on system performance. The hybrid methodology successfully addresses the computational limitations of traditional CFD approaches while maintaining high prediction accuracy, offering a practical solution for sustainable temperature management in cold storage applications. Finally, this research provides valuable insights for optimizing cold chain operations and demonstrates the potential of hybrid modeling approaches in thermal management systems. Full article

Sterilized processed cheese is a dairy product with prolonged shelf life compared to regular processed cheese. The extension of durability is made possible by the thermosterilization of processed cheese, while regular processed cheese is submitted to pasteurization process during manufacturing. Sterilized processed cheese can be classified as long-life foods and their shelf life may reach up to 24 months, if stored at ambient temperature (approx. 25 ± 1 °C). This fact is an advantage over regular processed cheese, which has a shelf life of only around 6 months. Sterilized processed cheese finds application in everyday life when refrigeration facilities are not available; i.e., it is intended for regular retail. However, their most important use is for storage in state material reserves and, moreover, for catering for members of the armed forces and/or members of the integrated rescue system. This review aimed to gather general information on sterilized processed cheeses, their characterization, usage and production. Furthermore, the review discusses the principles of sterilization and factors affecting the course of sterilization focusing on the setting the sterilization limits and sterilization parameters in order to maximize end-product quality. Moreover, last part of the review is devoted to the effect of sterilization and long-term storage on the qualitative parameters of sterilized processed cheese. Full article

Fruits are perishable fresh products with a short shelf life after harvesting. Perishable foods and their shelf lives are directly related to the temperature at which they are stored. Refrigeration is therefore essential in the conservation of fruits, as it allows the temperature to be lowered, helping to delay microbial, physiological, and chemical changes. This work aimed to compare the thermal behaviors of alveoli with different phase change materials (PCMs) placed inside a modular packaging developed for the transport and storage of fruits. The cooling tests were carried out inside a cold storage chamber with the set-point programmed to 2 °C. To simulate the placement in packages exposed to the store environment, heating tests were carried out while the chamber door was opened and the packaging was exposed to external environmental conditions. The phase change materials tested were RT2HC, RT5HC, and RT8HC. The temperature variation in the tests during cooling and heating proved that the new type of alveoli with PCM inside the fruit transport packaging is extremely important, as it can extend the useful life of the fruits after they are removed from the cold chamber, managing to maintain adequate conservation conditions for longer in contact with room temperature. The phase change material RT8HC was the one that showed the best results overall, managing to maintain the temperature of the fruit inside the packaging at a temperature below 10 °C for up to eight hours after being exposed to ambient conditions of 20 °C. Full article

The performance of a conventional Ground-Source Refrigeration and Air Conditioning (GSRAC) system with a borehole heat exchanger (BHE) can be enhanced by addressing the soil thermal imbalance issue that affects these systems. This study proposes a novel concept for seasonal cold energy storage using a Thermal Diode Tank (TDT). The TDT consists of an insulated water tank fitted with an array of heat pipes. By integrating the TDT into a conventional GSRAC system, “cold” energy can be passively collected from ambient air during winter, injected into the BHE, and stored in the soil. The stored “cold” energy can then be retrieved in the summer, facilitating cross-seasonal cold energy storage (CS). Thus, a conventional GSRAC system can be transformed into a GSRAC system with cross-seasonal cold energy storage capability, i.e., GSRAC + CS system. The validated BHE model previously developed by the authors is used to predict the performance improvements achieved using the GSRAC + CS system. The results indicate that the Annual Net Cold Energy Storage Efficiency (ANESE) increased from 5.7% to 10.7% over a ten year period. The average Borehole Performance Improvement (BPI) due to the addition of cold storage capability is 11% over the same timeframe. This study also discusses the impacts of varying design and operational parameters on ANESE and BPI. The results demonstrate that GSRAC + CS systems not only mitigate the soil thermal imbalance issue faced by conventional GSRAC systems, but also require less BHE depth to achieve equivalent performance. Full article

The Nutrient-upgraded Rodent Food Bar (NuRFB) is the standard diet for mice in NASA’s Rodent Research Project aboard the International Space Station (ISS). Given the nature of spaceflight and the lengthy production process of the food bars, a shelf-life assessment was conducted to evaluate nutritional stability over time (ranging from 0 to 27 months) and under different storage conditions (refrigerated, ambient, and refrigerated + ambient), where ambient is 22–23 °C. Lipid oxidation markers and fat- and water-soluble vitamins were assessed under various time and temperature conditions using AOAC International methods. Vitamin D levels showed a minor decrease, and riboflavin fluctuated slightly over time, but all vitamin levels remained above National Research Council (NRC) minimum requirements. Food bars stored at 4 °C showed significantly higher thiamine levels than the bars that underwent some degree of ambient temperature storage, but all met the NRC guidelines. Minimal lipid oxidation was observed for up to 18 months, and no mold or yeast growth occurred despite the high moisture content of the bars. This study confirms that NuRFBs maintain stable vitamin and lipid oxidation indices, ensuring adequate nutrition for rodents during spaceflight. Full article

The dynamics of the suction manifold of a high-fidelity simulation benchmark model of a modified supermarket refrigeration system created in MATLAB 2024a and Simulink 2024a is modeled using a nonlinear system identification technique. The original model consists of a cold storage room, three open display cases, the suction manifold, and the compressor rack. Since open display cases are less energy-efficient, they were removed, while the cold storage room with a door was used for simulation. The suction manifold model has two outputs: the suction pressure and the compressor’s power consumption; and it has three inputs: the mass flow of refrigerant, the ambient temperature, and the compressor capacity. A fourteen-day simulation was carried out, and synthetic data were generated from the input and output data of the simulation model. These data were divided into estimation data and validation data. Wavelet networks were then utilized to estimate and validate a nonlinear ARX model. The comparison between the estimation data and the validation data shows a goodness of fit of 87.8% for the suction pressure and 100% for the compressor power, with a simulation focus. The 100% fit for the compressor power occurred because wavelet networks provide excellent identification for nonlinear static systems and the compressor power response was based on static modeling assumption while the suction pressure response was based on dynamic modeling assumption. The data-driven identified model of the suction manifold was stable and robust and could handle strong nonlinearities of the input and output variables when used to replace the Simulink model of the suction manifold subsystem in the simulation benchmark. The simulation results clearly demonstrate how complex refrigeration system subsystems can be replaced with simpler and data-compliant data-driven models. Full article

This study aimed to compare the effects of ultrasonication and thermal treatments on the quality attributes of a lemon-based functional beverage. The beverage samples were subjected to different treatments and analyzed for physicochemical parameters and microbial load over a four-week refrigeration period. The thermal treatment involved exposing the beverage to a temperature of 70 °C for 10 min, resulting in a notable 30% increase in shelf life compared to the untreated samples. However, this thermal treatment led to a significant reduction in bioactive compounds, including a 15% decrease in polyphenols, a 20% decrease in flavonoids, and a 25% decline in ascorbic acid content. In contrast, sonication, performed at a temperature of 20 °C and a frequency of 37 kHz, effectively reduced the microbial load from 6.16 CFU/mL to 3.82 CFU/mL. The application of sonication also demonstrated a superior preservation of the nutritional properties and antioxidant content of the functional beverage compared to the thermal treatment. A storage analysis revealed that sonication maximized antioxidant levels when compared to thermal heating at a temperature of 4 °C. The findings of this study have significant implications for the food industry. Sonication emerged as a cost-effective and efficient alternative to thermal treatment for producing high-quality fruit beverages. Its ability to reduce microbial load while preserving nutritional properties makes it an attractive option for large-scale production. The integration of sonication into existing production processes is also feasible, as it requires minimal equipment and can be applied at ambient or controlled temperatures. In conclusion, this study highlights the advantages of using sonication as a non-thermal technique for enhancing the quality and safety of lemon-based functional beverages. The findings support the adoption of sonication in the food industry to meet the growing demand for functional and healthy beverages while maintaining the desired quality standards. Full article

The present study aimed to evaluate the use of agricultural waste as carriers in the bioformulation of two plant growth promoting bacteria (PGPR), Bacillus thuringiensis B9 and Bacillus pacificus B11 isolated from the tomato rhizosphere, and to determine the effect of different carriers and storage temperatures on bacterial survival. Three carriers, namely palm nut shell biochar, coffee pulp and soil, were inoculated with one of the strains, dehydrated and stored at ambient and refrigeration temperatures (4 °C). Bacterial survival was evaluated for 150 days at 30-day intervals. The results showed that the number of bacterial cells present in the bioformulations decreased progressively with storage time at room temperature, but at refrigeration temperature, the bacterial population initially decreased before increasing until reaching its maximum population at 90 days and gradually decreasing afterward. Although the coffee pulp and biochar carriers stored at 4 °C retained the viability of the bacterial strains as well as possible, the formulations stored at room temperature also remained viable. Full article

In a mass fatality incident (MFI), effective preservation of tissue samples is the cornerstone for downstream DNA-based identification of victims. This is commonly achieved through freezing of tissue samples excised from bodies/fragmented remains which may be buried or stored in refrigerated containers. This may, however, not be possible depending on the nature of the MFI; in particular, during armed conflict/war where extended periods of electrical outages would be expected. The present study compared the effectiveness of long-term tissue preservation at ambient temperatures using two commercial products (non-iodized kitchen salt and a 40% alcoholic beverage) against a chemical preservative (Allprotect™ Tissue Reagent (Qiagen, Germantown, MD, USA)) and freezing at −20 °C. Bovine muscle tissue, used as a proxy for human tissue, was treated with the four preservation methods and sampled at six different time-points over a 24-month period. All four methods were able to preserve the bovine tissue, generally yielding STR-PCR (Short Tandem Repeat-Polymerase Chain Reaction) amplicons > 200 bp in size even at the end of 24 months. Gel electrophoresis, however, indicated that salt was more effective in preserving DNA integrity with high-molecular-weight DNA clearly visible as compared to the low-molecular-weight DNA smears observed in the other methods. This study also proposes a simple process for the rapid and low-cost preservation of tissue samples for long-term storage at ambient temperatures in support of post-incident victim identification efforts. Full article

Reflux esophagitis, a treatment for gastric ulcers known as Ilaprazole (Ila), is not stable during storage and handling at room temperature, requiring storage at 5 degrees Celsius. In this study, to address these issues with Ila, coformers rich in oxygen (O) and hydroxyl (OH) groups capable of forming hydrogen bonds with were selected. These coformers included Xylitol (Xyl), Meglumine (Meg), Nicotinic acid (Nic), L-Aspartic acid (Asp), and L-Glutamic acid (Glu). A 1:1 physical mixture of Ila and each coformer was prepared, and the potential for cocrystal formation was predicted using differential scanning calorimetry (DSC) screening. The results indicated the potential for cocrystal formation in the Ila/Xyl physical mixture. Subsequently, Ila and Xyl were mixed in ethyl acetate (EA) in a 1:1 ratio, and after 28 h of slurry, the formation of Ila/Xyl cocrystal was confirmed through solid-state CP/MAS ¹³C NMR spectrum analysis, showing intermolecular hydrogen bonding and conformational changes. Furthermore, the 1:1 ratio of Ila/Xyl cocrystal was confirmed through solution-state NMR (¹H, ¹³C, and 2D) molecular structure analysis. To assess the stability of Ila/Xyl cocrystal at room temperature, it was stored and compared with Ila at 25 ± 2 °C and relative humidity (RH) of 65 ± 5% over three months. The results showed that the purity of Ila/Xyl cocrystal remained at 99.8% from the initial purity of 99.75% over the three months, while Ila was predicted to decrease from an initial 99.8% purity to 90% after three months. Additionally, at 25 ± 2 °C and RH 65 ± 5%, a specific impurity B in Ila/Xyl cocrystal was observed to be 0.03% over three months, whereas Ila was predicted to increase from an initial 0.032% to 2.28% after three months. To evaluate the dissolution rate of Ila/Xyl cocrystal, a formulation was prepared and compared with Ila at pH 10, with a dosage equivalent to 10 mg of Ila. The results showed that Ila/Xyl cocrystal reached 55% within 15 min and 100% within 45 min, while Ila was predicted to reach 32% at 15 min and 100% only after 60 min. However, overall, the Ila/Xyl cocrystal showed results equivalent to or exceeding the dissolution rate of Ila. Therefore, it is predicted that the Ila/Xyl cocrystal will maximize its effectiveness as a more convenient crystal structure for formulation development, allowing storage and preservation at room temperature without the need for the problematic 5 °C refrigeration during ambient conditions and storage, addressing the issues associated with Ila. Full article

Coconut is naturally sealed with coconut water inside. Microbial contamination occurs only after the seal is broken during extraction. This study evaluated changes in the microbiological, physicochemical, and chemical properties of coconut water during postharvest storage at ambient and refrigerated temperatures. Initial microbial counts ranged from 2 to 5 log CFU/mL, while physicochemical factors, including total soluble solids (TSSs), pH, and sugar content (4–7 °Brix, 5.0–5.5, 4–6% g/100 mL), were consistent. The dynamic changes in the physicochemical properties of coconut water stored under both conditions exhibited a clear correlation with the increased microbial populations. Fructose was the primary sugar, with citric and malic acids as major acids, while the predominant volatile compounds were ethanol, ethyl acetate, ethyl ester, acetic acid and octanoic acid. Storage conditions led to similar microbial and physicochemical changes, but ambient temperature accelerated spoilage 10 times faster than refrigeration. Sucrose decreased steadily, whereas fructose and glucose remained stable until a precipitous decline coincided with lactic acid bacteria (LAB) reaching >6 log CFU/mL on the final day of storage. Weissella cibaria and Leuconostoc spp. are the main species in coconut water. The presence of specific volatile compounds, including octanoic acid, acetic acid, ethyl acetate, and butyl phenol, is associated with the activities of Lactobacillus, particularly Weissella. There was a clear relationship among microbial groups and populations, total titratable acidity (TTA), and sensory criteria. Remarkably, TTA was closely correlated with total plate count (TPC) (>5 log CFU/mL) and an unacceptable sensory rating. Full article

Cold brew coffee (CBC) has gained in popularity due to its distinct sensory experience. However, CBC can pose a risk for bacterial pathogens if not stored properly. High-Pressure Processing (HPP) is a nonthermal technology that can improve the safety of CBC while maintaining its quality. In this study, CBC made from ground roasted coffee grains was processed at 600 MPa for 3 min and stored at 4 or 23 °C for 90 days. The microbiological quality indicators remained stable throughout the study period. Physicochemical and quality parameters, such as pH, total dissolved solids, titratable acidity, color, total phenolic compounds and antioxidant activity, were not significantly affected by HPP. Both unprocessed and HPP CBC samples showed changes in pH, titratable acidity and color stability after 60 days at 23 °C. Unprocessed CBC samples spiked with Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enterica showed decreased counts, but the pathogens were still detectable after 60 days at 4 °C and after 90 days at 23 °C. HPP achieved a >6-log₁₀ reduction in the species tested, with non-detectable levels for at least 90 days at both storage temperatures. These findings suggest that HPP can effectively control vegetative pathogens and spoilage microorganisms in CBC while preserving its quality attributes. Full article

Stool sampling is a useful tool for diagnosing gastrointestinal disease in veterinary medicine. The sub-clinical disease burden of Salmonella spp. in cattle can become significant for farmers. However, current methods of faecal sampling in a rural setting for diagnosis are not consistently sufficient for the preservation of Salmonella spp. in faeces. This study evaluated the use of a commercial stool storage kit for bacterial preservation in cow faecal samples compared to unpreserved stools placed into refrigeration at different time-points. A stool sample was collected per-rectum from one apparently healthy Holstein–Freisen cow. The sample was weighed and aliquoted into two sterile Falcon tubes and into two commercial kit tubes. The aliquots were then placed into refrigeration at 4 °C at 0, 24, and 96 h after processing. One commercial kit tube was not aliquoted and remained at ambient temperature. After 2 weeks, DNA was extracted from the samples and analysed using endpoint PCR, revealing a sub-clinical infection with Salmonella spp. The bacterium was best preserved when the stool was stored in the commercial kit at ambient temperature and re-homogenised immediately prior to DNA extraction. The unpreserved stool did not maintain obvious levels of Salmonella spp. after 24 h at ambient temperature. This commercial kit should be considered for use in the diagnosis of salmonellosis in cattle. Full article