Search Results (257)

Peach consumers demand good quality fruit, but premature harvests result in fruit that does not ripen properly and does not reach the required organoleptic quality, so consumers stop buying this product that does not meet their expectations. In our region, peaches are exported long distances, and it is required that when they reach the destination market their quality is adequate. Therefore, the objective of this study was to determine the storage capacity of commercial and delayed harvest in three peach cultivars. ‘Rich Lady’, ‘Summer Lady’, and ‘Merryl O’Henry’ were harvested at commercial maturity (H1) and, a few days later (H2), packed in passive modified atmosphere (PMA), and stored under refrigeration for up to 40 days to simulate marketing to distant markets. During storage and after three days of shelf-life, the physico-chemical characteristics, damage, and sensory quality of the fruit were analyzed. In general, after cold storage, peaches improve their sensory characteristics after three days at room temperature. PMA with refrigeration was suitable for exporting ‘Rich Lady’ peaches overseas for H1. The late harvest, H2, is recommended for ‘Summer Lady’, as it improves sensory quality without losing storability. ‘Summer Lady’ was the best-rated cultivar by the tasters, and ‘Merryl O’Henry’ the worst, due to its lack of ripening and high incidence of chilling injury. Full article

As a natural refrigerant, CO₂ shows significant potential in sustainable thermal engineering due to its environmental safety and economic viability. While the transcritical CO₂ cycle demonstrates strong performance in heating, low-temperature applications, and integration with renewable energy sources, its widespread adoption is hindered by key challenges at the application level. These include: high sensitivity of system efficiency to operating conditions, which creates an “efficiency hump” and narrows the optimal operating window; increased component costs and technical challenges for key devices such as multi-channel valves due to high-pressure requirements; and complex system control with limited intelligent solutions currently integrated. Despite these challenges, the transcritical CO₂ cycle holds unique value in enabling synergistic energy conversion. Its ability to efficiently match and cascade different energy grades makes it particularly suitable for data center cooling, industrial combined cooling and heating, and solar–thermal hybrid systems, positioning it as an indispensable technology in future low-carbon energy systems. To fully realize its potential, development efforts must focus on high-value applications and key technological breakthroughs. Priority should be given to demonstrating its use in fields where it holds a distinct advantage, such as low-temperature refrigeration and high-temperature industrial heat pumps, to establish commercially viable models. Concurrently, core technologies—including adaptive intelligent control algorithms, high-efficiency expanders, and cost-effective pressure-resistant components—must be advanced. Supportive policies, encompassing energy efficiency standards, safety regulations, and fiscal incentives, will be essential to facilitate the transition from demonstration projects to widespread industrial adoption. Full article

The global food industry is undergoing a major shift driven by increasing consumer demand for clean-label and naturally preserved foods. Fresh pasta is highly vulnerable to fungal damage because of its high water activity (a_w > 0.85), typically ranging between 0.92 and 0.97, moderate to near-neutral pH (around 5.0–7.0), and nutrient-rich composition, all of which create favorable conditions for fungal growth during refrigeration, mainly by genera such as Penicillium and Aspergillus. Fungal contamination results in significant economic losses due to reduced product quality and poses potential health risks associated with mycotoxin production. Although conventional chemical preservatives are relatively effective in preventing spoilage, their use conflicts with clean-label trends and faces growing regulatory and consumer scrutiny. In this context, antifungal lactic acid bacteria (LAB) have emerged as a promising natural alternative for biopreservation. Several LAB strains, particularly those isolated from cereal-based environments (e.g., Lactobacillus plantarum and L. amylovorus), produce a broad spectrum of antifungal metabolites, including organic acids, phenylalanine-derived acids, cyclic dipeptides, and volatile compounds. These metabolites act synergistically to inhibit fungal growth through multiple mechanisms, such as cytoplasmic acidification, energy depletion, and membrane disruption. However, the application of LAB in fresh pasta production requires overcoming several challenges, including the scale-up from laboratory to industrial processes, the maintenance of metabolic activity within the complex pasta matrix, and the preservation of desirable sensory attributes. Furthermore, regulatory approval (GRAS/QPS status), economic feasibility, and effective consumer communication are crucial for successful commercial implementation. This review analyzes studies published over the past decade on fresh pasta spoilage and the antifungal activity of lactic acid bacteria (LAB), highlighting the progressive refinement of LAB-based biopreservation strategies. The literature demonstrates a transition from early descriptive studies to recent research focused on strain-specific mechanisms and technological integration. Overall, LAB-mediated biopreservation emerges as a sustainable, clean-label approach for extending the shelf life and safety of fresh pasta, with future developments relying on targeted strain selection and synergistic preservation strategies. Full article

This study presents an Adaptive PID controller designed to enhance temperature stability and energy performance in household refrigerator systems subject to non-stationary disturbances. Classical PID control is limited by fixed gains and the assumption of linear time-invariant dynamics, which is frequently violated by door opening, load variation, and compressor cycling. To address this issue, the proposed approach introduces a Laplace-distribution-based adaptive gain function L(t) that adjusts controller sensitivity according to the statistical rarity of the composite temperature error. The method preserves the conventional PID control structure while introducing a lightweight gain-scaling mechanism suitable for embedded implementation. Experimental validation using a commercial two-compartment refrigerator demonstrated substantial improvements in performance compared with a classical PID controller. The Adaptive PID achieved reduced temperature deviations in both compartments, significantly smoother compressor and fan actuation, and a 4.6% reduction in total energy consumption under an identical disturbance schedule. These results confirm that the proposed controller provides a practical, embedded-friendly solution that improves thermal regulation, actuator longevity, and energy efficiency under the tested disturbance schedule representative of typical household usage. Full article

The red prickly pear (Opuntia streptacantha) is a fruit that is distinguished by its sensory properties and high content of bioactive compounds. Its rapid spoilage rate significantly impacts its commercialization, underscoring the urgent need for effective preservation methods. This study investigated the effectiveness of various juice preservation techniques—refrigeration, freezing, pasteurization, and vacuum packaging —in maintaining the microbiological quality, physicochemical properties, and antioxidant capacity of red prickly pear juice during storage. The most effective preservation method was found to be freezing the vacuum-packaged and pasteurized juice, referred to as J4. This method adequately maintained key nutritional and physicochemical qualities after 12 months, which was evidenced by a reduction in the microbial growth and the preservation of pH (4.64), acidity (0.74 g citric acid L⁻¹), antioxidant activity (2.6–2.9 mmol TE L⁻¹), as well as the content of phenols (506 mg GAE L⁻¹), betalains (141.2 mg L⁻¹), and total sugars (125 g L⁻¹). Furthermore, sensory analysis comparing J4-treated juice to control juice revealed no significant differences, confirming that J4 is an effective method for preserving the nutritional, functional, and sensory qualities of red prickly pear juice. Full article

Blossom-end enlargement (BEE) is a physiological disorder in cucumbers (Cucumis sativus L.) that affects postharvest quality and results in commercial loss due to reduced product value. Pre-cooling using modified atmosphere packaging (MAP) has been encouraged as a preventive method of BEE; however, BEE can still be observed under actual distribution conditions. This study reexamined the process from harvesting in midsummer to arriving at the market (550 km) and storage, while considering the impact of packaging materials, packaging methods, and human factors on BEE occurrence. More than 18 h were required from harvest to delivery at the pre-cooling warehouse at the common shipping site; however, despite using a refrigerated truck, the temperature inside the packaging increased again during transportation. The temperature then dropped during 24 h of pre-cooling; however, it did not reach 10 °C, the appropriate storage temperature for cucumbers. MAP suppressed the occurrence of BEE compared to conventional film packaging; however, the BEE index varied greatly between individuals who performed the packaging. We determined that tying both ends of the packaging film increases the degree of airtightness as individual differences decrease and is more effective at suppressing BEE. Porous mineral-containing film (PM) packaging, which generates a modified atmosphere (MA), significantly suppressed BEE compared to conventional perforated film (C). In 2019 transport trials, the BEE index at 6 DAH for C film was 77.3, while for PM film it was only 12.0. Furthermore, we found that the effectiveness of PM film was significantly affected by human-related operational factors. The novel packaging method of tying both ends of the film (PM-T) provided the most consistent BEE suppression and lowest BEE index regardless of the packaging worker, demonstrating its superior potential in standardizing airtightness and minimizing human-related operational variability. Full article

Cold-pressed chia oil (Salvia hispanica L.) is highly susceptible to oxidative deterioration due to its exceptional α-linolenic acid content. This study evaluated the effect of increasing α-tocopherol concentrations (0–0.10% w/w) on its oxidative stability through accelerated oxidation testing (Oxitest) and long-term refrigerated storage. α-Tocopherol was selected because it is a widely accepted antioxidant in edible oils according to the Codex Alimentarius and FAO/WHO guidelines. A randomized block design (n = 3 independent extraction batches) was used to determine the induction period (IP) at 80 °C, followed by a 15-month evaluation at 15 °C of the control and the most promising treatment. α-Tocopherol increased oxidative resistance in a dose-dependent manner, but concentrations above 0.05% offered no additional benefits. The 0.05% treatment significantly prolonged the IP and effectively limited increases in peroxide and acidity values, keeping all parameters within Ecuadorian regulatory limits and consistent with international quality standards. Fatty-acid profiling confirmed that this antioxidant level slowed α-linolenic acid degradation, preserving the PUFA-rich profile of chia oil. These findings show that low-level α-tocopherol supplementation is a practical strategy to improve long-term stability of cold-pressed chia oil without altering its nutritional properties, providing valuable evidence for the formulation and commercialization of premium functional oils. Full article

The combination of rapeseed oil (RO) and hazelnut oil (HO) was selected to create a functional blend integrating two technologically complementary lipid matrices. RO is valued for its favorable fatty acid (FA) profile, particularly its low saturated FA content and the presence of essential polyunsaturated FAs, whereas HO is characterized by high monounsaturated FA levels and inherently greater resistance to oxidative deterioration. Blending these oils enables the formulation of mixtures that balance nutritional quality with improved physicochemical stability, without the need for chemical modification. Such an approach is relevant for applications requiring oils that retain desirable characteristics during storage and handling. In this context, the present study aimed to evaluate the quality characteristics, FA composition, triacylglycerol (TAG) structures, and oxidative stability of binary blends of RO and HO. Two commercial oils, as well as their blends in RO:HO volume ratios of 3:1, 1:1, and 1:3, were tested. The samples were stored under two temperature conditions: 4 °C (refrigeration) and 20 °C (room temperature), and analyzed after two and four months of storage. Initial MUFA content ranged from approx. 61–74%, increasing with HO proportion, whereas PUFA levels decreased accordingly (from ~28% in RO to ~10% in HO-rich blends). The sn-2 TAG position was predominantly occupied by unsaturated FAs (>80%). Statistical analysis (p < 0.05) showed that both storage time and temperature significantly affected PV, while no significant differences were observed in the overall proportions of SFA, MUFA, and PUFA. Blends with a higher proportion of RO exhibited increased AVs, suggesting greater susceptibility to hydrolytic changes, whereas mixtures enriched in HO demonstrated superior oxidative stability, as reflected by significantly lower peroxide values (p < 0.05), which can be attributed to their lower PUFA content. The 1RO:3HO blend exhibited the most favorable balance between beneficial nutritional indices and stability against quality deterioration over the storage period. The results indicated that the formulation of balanced mixtures combining the favorable FA profile of RO with the oxidative resistance of HO represents a promising approach for obtaining oils with improved functional and nutritional properties. Full article

The paper identifies and describes the possibilities for heat and mechanical energy recovery within refrigeration systems using CO₂ as a working fluid, employed in commercial and industrial applications. The heat and mechanical energy recovery methods that can be utilized for beneficial purposes are taken into consideration. These methods could increase the energy efficiency of the refrigeration system or the building in which it operates. This paper summarizes various configurations and recovery methods and critically compares and evaluates them (COP improvements, exergy performance, and system integration complexity) based on the data available in the literature. As a result, the internal heat exchangers can be used as a superheater, in which case the COP can increase to 35%. If the internal heat exchanger is used as a subcooler, it could lead to a COP increase of 17% compared to a CO₂ refrigeration system without subcooling for an evaporating temperature of −10 °C and the temperature of the gas cooler outlet of 30 °C. The heat and mechanical energy recovery possibilities are presented using the available scientific literature. Full article

Prized since antiquity in Greek cultural heritage as a fountain of health and healing and nature’s golden nectar, honey remains one of the world’s most valued natural products. Celebrated for its nutritional, therapeutic, and antimicrobial virtues, honey is now faced with the emerging threat of microplastic contamination. Here, we present direct evidence of microplastic migration into honey, examining real honey samples packaged in flexible plastic pouches, which are commonly offered in cafes all around the world. Such honey samples were tested under different environmental storage conditions (common dry and dark outdoors) and prolonged refrigeration conditions at low temperature, which replicate consumer use. We have identified microplastics using filters and spectroscopic methods in honey from commercial honey pouches, which prove plastic packaging as a contamination source. Additionally, plasticizers were detected in honey that migrated from plastic packaging. The mere fact that microplastics were found in every single storage condition tested and at every time point examined (from day zero of this experiment), while increasing through time, is of great concern for the long-term safety of honey packaging. Our findings emphasize the urgency of reevaluating packaging for honey and other foods, and they open up new perspectives in the study of microplastic migration under real-world conditions. Full article

Multi-object tracking faces persistent challenges from occlusions and truncations in monocular vision systems. While stereo vision provides depth information, existing approaches require computationally expensive dense matching or 3D reconstruction. This paper presents a real-time 2.5D stereo multi-object tracking framework combining lightweight stereo matching with resilient tracker management. The stereo matching module employs Direct Linear Transform-based triangulation using only bounding box coordinates, eliminating costly feature extraction while maintaining robust correspondence through geometric constraints. A dual-tracker architecture maintains independent trackers in both views, enabling re-identification when objects become occluded in one view but remain visible in the other. Experimental validation on a refrigerator monitoring dataset demonstrates that StereoSORT achieves a multiple object tracking accuracy (MOTA) of 0.932 and an identification F1 score (IDF1) of 0.823, substantially outperforming monocular trackers, including OC-SORT (IDF1: 0.765) and ByteTrack (IDF1: 0.609). The system achieves a 50.1 mm median depth error, comparable to commercial sensors, while maintaining 70 FPS on standard hardware. These results validate that geometric constraints alone enable robust stereo tracking without appearance features, offering a practical solution for resource-constrained environments where computational efficiency and tracking reliability are equally critical. Full article

The present study aims to compare the chemical composition of samples of jerked beef commercialized in Brasilia, Brazil, subjected to diverse desalting techniques (room temperature, refrigerated, and heat desalting). This experimental study was divided into five steps: determination of desalting techniques, chemical composition, determination of titratable acidity and pH, sodium analysis of the samples, and statistical analysis. The control samples showed high sodium levels (>6000 mg/100 g), confirming the need for desalting to ensure suitability for consumption. Desalting at room temperature was the most efficient, reducing sodium content by up to 76%, followed by refrigeration (67–74%) and the heat method (52–58%). It was also observed that the desalting technique significantly affects the chemical composition. Desalting at room temperature and under refrigeration increased moisture (54.12→73.82 g/100 g) and reduced proteins (23.50→18.70 g/100 g) and lipids (3.70→3.00 g/100 g) through a dilution effect, while desalting in heat concentrated solids, increasing protein (31.29 g/100 g), lipids (4.19 g/100 g), and lipid oxidation (TBARS = 91.79 µmol MDA/kg) in comparison to control samples (38.63 µmol MDA/kg). Acidity and pH showed minor variations but correlated with lipid oxidation processes. Although no technique eliminates excess sodium, the results reinforce that desalting at room temperature offers the best balance between sodium reduction and preservation of the product’s nutritional quality and oxidative stability, making it the most suitable method for use in restaurants and at home. Full article

The increased consumption of ready-to-eat fruits highlights the need for better control of microbial growth during their shelf life. Among bacteria, Staphylococcus aureus and Bacillus cereus are proposed as target species for testing alternative preservative methods. This study aimed to evaluate the antimicrobial effect of the cell-free supernatant (CFS) from LAB strains previously isolated from ready-to-eat fruits, used as a mixed solution, against both reference and native S. aureus and B. cereus, which were isolated from commercial ready-to-eat fruits. A specific challenge test was conducted on minimally processed orange slices, assessing the effect of CFS on the intentionally inoculated target bacteria using a culturing and quantitative PCR (qPCR) approach. Microbiological counts varied widely among samples, indicating an initial microbiota below legislative limits, mainly comprising total mesophilic and psychrophilic bacteria, which increased significantly after 8 days of storage. Additionally, our results demonstrated the food matrix’s capacity to support the growth of both target species, with the tested CFS mainly effective in reducing the growth of reference strains. The results of the physicochemical analyses showed that during refrigerated storage, the orange slices underwent changes in pH, color, and texture, mostly in S. aureus strain-inoculated samples, negatively affecting texture at mid-storage time. The study also underscored the importance of combining plate counting with qPCR methods to detect B. cereus, as it can be risky even at low levels. Full article

Commercial buildings and shopping malls face rising electricity costs and increasing pressure to adopt sustainable practices. This paper presents the first long-term, multi-site empirical validation of Automatic Voltage Regulator (AVR) deployment in Thai retail facilities, providing robust evidence for tropical, motor-heavy load contexts. The study evaluates the engineering, economic, and environmental performance of an AVR with an autotransformer core under real operating conditions. High-resolution measurements were collected before and after AVR installation, using Class 0.2s analyzers and a Building Energy Management System (BEMS) across multiple branches during a four-month monitoring campaign (February–May). Results indicate that a modest voltage reduction of 8.06% yielded a 12.02% decrease in active power demand, a 6.22% current reduction, and a 2.26% improvement in power factor. The greatest savings occurred in HVAC (8.19%) and refrigeration loads (8.20%), while lighting loads remained nearly unchanged. Economically, the system delivered ~177 kWh/day savings, equivalent to 262,212 THB/year, with a simple payback of 2.67 years and an ROI of 37.5%. Environmentally, the AVR reduced 36.6 tCO₂/year (±5%), aligning with Thailand’s Energy Efficiency Plan (EEP) 2018–2037 and Carbon Neutrality Roadmap and offering additional potential for T-VER monetization. These findings confirm AVR technology as a scalable, standards-compliant, and high-return retrofit solution for commercial facilities in tropical climates. Full article

The lion’s paw scallop (Nodipecten subnodosus) is a commercially valuable pectinid whose postharvest quality strongly depends on storage and handling conditions. This study investigated the combined effects of seasonality, postmortem time, and storage temperature on energy metabolism in the adductor muscle, focusing on metabolites associated with rigor mortis and freshness. Adult scallops (~10 cm shell height) were harvested in four seasons (spring, summer, autumn, winter), transported under commercial conditions for approximately 2 h, and stored at 0, 5, and 10 °C for 48 h. Muscle samples were collected every 8 h and analyzed for ATP, ADP, AMP, glycogen, arginine phosphate (Arg-P), and free arginine using HPLC and enzymatic assays. In addition, the adenylate energy charge (AEC) was determined in freshly harvested and post-transport specimens. Initial ATP concentrations ranged from 4.2 to 6.5 µmol/g, with higher levels in winter, while Arg-P varied from 3.1 to 4.8 µmol/g. Seasonality significantly influenced all metabolites except arginine, and transport markedly reduced ATP and AEC, particularly in spring and autumn. Storage at 0 °C resulted in rapid ATP depletion (<1.0 µmol/g within 12 h) and AMP accumulation (>3.0 µmol/g), indicating accelerated energy collapse. In contrast, scallops stored at 5 and 10 °C maintained ATP levels above 2.5 µmol/g for up to 24 h, delaying rigor mortis, reducing postmortem contraction, and preserving muscle texture and appearance. Overall, these findings demonstrate that moderate refrigeration represents a physiologically suitable and technologically advantageous strategy to optimize scallop postharvest handling, extend shelf life, and enhance product quality for the fresh seafood market. Full article