Changes In Quality Parameters Research Articles

Evaluation of low-cost sensors to integrate in a water quality monitor for real-time measurements.

Low-cost sensors integrated with the Internet of Things can enable real-time environmental monitoring networks and provide valuable water quality information to the public. However, the accuracy and precision of the values measured by the sensors are critical for widespread adoption. In this study, 19 different low-cost sensors, commonly found in the literature, from four different manufacturers are tested for measuring five water quality parameters: pH, dissolved oxygen, oxidation-reduction potential, turbidity, and temperature. The low-cost sensors are evaluated for each parameter by calculating the error and precision compared to a typical multiparameter probe assumed as a reference. The comparison was performed in a controlled environment with simultaneous measurements of real water samples. The relative error ranged from 0.33 to 33.77%, and most of them were 5%. The pH and temperature were the ones with the most accurate results. In conclusion, low-cost sensors are a complementary alternative to quickly detect changes in water quality parameters. Further studies are necessary to establish a guideline for the operation and maintenance of low-cost sensors.

Quality changes in high hydrostatic pressure treated enriched tomato sauce.

Use of high hydrostatic pressure (HHP) with reduced processing times is gaining traction in the food industry as an alternative to conventional thermal treatment. In order to enhance functional benefits while minimizing processing losses, functionalized products are being developed with such novel techniques. In this study, changes in quality parameters for HHP treated enriched tomato sauce were evaluated, with the aim to assess its viability as an alternative to conventional thermal treatment methods. HHP treatments at 500 MPa, 30 °C/50 °C significantly increased the total phenolic and lycopene content of the sauce samples, achieving 6.7% and 7.5% improvements over conventionally treated samples. The antioxidant capacity of the HHP-treated samples was also found to match or be better than conventionally treated samples. Furthermore, a T2 relaxation time study revealed that pressure-temperature processing treatments were effective in maintaining the structural integrity of water molecules. Microbiological analyses revealed that 500 MPa/50 °C 5 min treatment can offer 8 logs reduction colony formation, matching the results of conventional thermal treatment. Combined pressure-temperature treatments improve results, reduce time consumption. 500 MPa/50 °C treatments provided retention of quality parameters and significant reduction in microbial activity. © 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.

Functional assessment of differentiated therapeutic approach effectiveness in ovarian cancer treatment: impact on qol and survey results

Background. Ovarian cancer presents a formidable challenge, primarily due to the high prevalence of resistance to platinum drugs, which hampers treatment success. Despite notable strides in chemotherapy regimens, over 40% of patients remain unresponsive to initial treatment. Delving into the underexplored realm of functional assessment regarding treatmentʼs impact on patientsʼ quality of life emerges as pivotal for refining therapeutic outcomes and enhancing their well-being. The absence of standardized evaluation methods and limited data underscore the imperative for further investigation into understanding how different treatment modalities influence patientsʼ quality of life. Leveraging questionnaires such as the EORTC QLQ-C30 and FACT-G proves invaluable in gauging this aspect of healthcare. Integrating the findings of quality of life assessments into clinical practice promises to catalyze the development of optimal therapeutic strategies tailored to enhance the well-being of ovarian cancer patients. Purpose – is to investigate how a tailored therapeutic approach influences the quality of life among patients grappling with platinum-resistant ovarian cancer. Our focus extends to considering the degree of pharmacoresistance alongside the utilization of varied chemotherapy strategies. Materials and methods. The study was conducted at the University Clinic of the Odessa National Medical University spanning from 2014 to 2024. A cohort of 350 patients diagnosed with stage III-IV ovarian adenocarcinoma, who had undergone cytoreductive surgeries, formed the basis of our research. This investigation adhered to the clinical protocol approved by the Ministry of Health of Ukraine. The methodology of our differentiated treatment strategy involved predicting patientsʼ responses to platinum-based therapy, classifying them as platinum-refractory, resistant, or sensitive. Subsequently, patients were categorized into four clinical groups based on the treatment regimens employed. To assess the quality of life, we utilized hierarchical clustering methodology along with the EORTC QLQ-C30 and FACT-G questionnaires. Evaluations were conducted at 6 and 12 months post-treatment completion. Results and discussion. Patiens of different groups had different symptoms and side effects: those who received standard chemotherapy had leukopenia and other side effects; those who received doxorubicin complained of nausea and stomatitis. Patients with comprehensive metabolic support had a smaller number of subjective complaints. During the catamnestic follow-up, we detected changes in parameters of quality of life, which may be associated with treatment of ovarian cancer. The differentiated treatment approach led to improvement of quality of life, decrease in side effects, and better well-being of the patients. These changes remained stable for a long period of time after cessation of active treatment, thus encouraging the use of a similar approach in the future. The results confirm the importance of an individualized treatment with metabolic support for achieving better clinical results and improving quality of life of patients with ovarian cancer. Conclusions. Our study underscores the effectiveness of a differentiated therapeutic approach in managing ovarian cancer, considering both pharmacoresistance levels and diverse chemotherapy strategies, thereby enhancing patientsʼ quality of life. Notably, cytoreductive surgeries and varied chemotherapy regimens yielded distinct side effects and symptoms among patients, contingent upon the treatment modalities applied. Encouragingly, post-active treatment phases witnessed a consistent amelioration in patientsʼ quality of life, underscoring the pivotal role of individualized approaches complemented by metabolic support in fostering superior clinical outcomes.

Delayed Luminescence in Monitoring the Postharvest Ripening of Tomato Fruit and Classifying According to Their Maturity Stage at Harvest

AbstractRipening is an irreversible phenomenon involving several physiological, biochemical and organoleptic changes that affect the nutritional value, colour, texture and taste of fruit. Amongst the physical non-destructive technologies, Delayed Luminescence (DL) has been reported able to provide valid information on the functional status of living biological systems, reflecting changes in quality parameters following the occurrence of certain metabolic processes. In this study, we followed up and analysed the variations in the colour and DL signals emitted by tomato fruit as a function of their ripening degree. Four lots of tomato fruit, similar to each other for cultivar and geographical origin, were considered. Tomatoes were harvested at various maturity stages and stored in the dark at room temperature. The changes in DL emission trends were monitored at different times after harvesting for a period of about 20 days and correlated with the a*/b* colour ratio, which is normally used as an indicator of fruit ripeness degree. Results highlighted that the emission intensities, as well as the parameters by fitting DL decay curves, were strongly dependent on harvest maturity, varying significantly even as fruit ripeness progressed after their harvesting. Significant differences were also found between DL signals emitted by field-ripened tomatoes at the beginning of storage and those emitted by postharvest-ripened tomatoes at the end of the storage period. Delayed Luminescence may be used as a fast, reliable and sensitive tool for evaluating, more generally, the sensorial quality of fruit during postharvest storage.

Pulsed electric field processing of fruit juices with inactivation of enzymes with new inactivation kinetic model and determination of changes in quality parameters

Pulsed electric fields (PEF) processing of fresh grape, orange and tomato juices by 17.2–24.1 kV/cm electric field strengths, 130.0–1040.5 μs treatment times and 1.43–29.13 J/kg energies with respect to determination of the changes in the physical and bioactive properties, color parameters in addition to inactivation of pectin methyl esterase (PME), polyphenol oxidase (PPO), and lipoxygenase (LOX) enzymes were studied. In general, decrease in pH, increase in conductivity (except for grape juice), total phenolic substance content, and total antioxidant capacity with no significant change (p > 0.05) in total soluble solids were observed by PEF treatment for all juices. Except for hue value for orange juice, no significant changes (p > 0.05) were observed in color values. Inactivation of the enzymes were increased with increased energy, and calculated electrical activation energies for PME, PPO, and LOX enzymes were 8.31, 7.06, and 4.31 kJ/mol, respectively. Industrial relevanceEnzymes in addition microorganisms causing quality degradation is of great concern in fruit juice industry as most of the enzymes are resistant to processing technologies. Increased PEF treatment time provided over 95% inactivation on PME, PPO, and LOX enzymes with no adverse effect on quality properties of grape, orange, and tomato juices revealing a viable alternative to juice processing industry.

Changes in quality parameters and bioactive components of seedless lime fruit (Citrus latifolia) during cold storage

The postharvest maintenance quality of fruits is significant for industrial applications. The present study was conducted to evaluate of quality parameters and bioactive components of seedless lime (Citrus latifolia) fruit during cold storage. Lime fruits were packed in perforated polyethylene bags, which were then put into a perforated expanded polystyrene box, and stored in a cool chamber, at 10°C. Quality parameters including skin color, weight loss, total soluble solids (TSS), juice percentage, technological index, titratable acidity (TTA), reducing and total sugars of the fruits were measured during 56 days of storage. The total phenolic content of the juices was measured using a colorimetric method of Folin-Ciocalteu. Ascorbic acid and major flavonoids of the fruits such as hesperidin and eriocitrin were quantified using HPLC-PDA methods. The results showed that cold storage kept the greenness of the fruit’s skin for up to 28 days. A minor weight loss (< 5%) was also recorded in the first 28 days of storage. The technological index of the fruits, reducing total sugars and TSS slightly increased, whereas TA somewhat decreased. Bioactive components such as phenolic and ascorbic acid contents were kept stable (p>0.05) in the first 21 days of storage but considerably reduced after 28 days of storage. A decrease in hesperidin and eriocitrin was also recorded from 21 days of storage but at a lower rate compared to that of phenolic and ascorbic acid contents. Altogether, a simple, convenient cold storage method using a perforated polyethylene bag and expanded polystyrene box can retain the quality and bioactive components of lime fruits for at least 21 days. The findings are significant for the food industrial application of storage lime fruits for fresh utilization or juice processing.

Incorporation of climate change into a multiple stressor risk assessment for the Chinook salmon (Oncorhynchus tshawytscha) population in the Yakima River, Washington, USA.

One outcome of the 2022 Society of Environmental Toxicology and Chemistry Pellston Workshop on incorporating climate change predictions into ecological risk assessments was the key question of how to integrate ecological risk assessments that focus on contaminants with the environmental alterations from climate projections. This article summarizes the results of integrating selected direct and indirect effects of climate change into an existing Bayesian network previously used for ecological risk assessment. The existing Bayesian Network Relative Risk Model integrated the effects of two organophosphate pesticides (malathion and diazinon), water temperature, and dissolved oxygen levels on the Chinook salmon population in the Yakima River Basin (YRB), Washington, USA. The endpoint was defined as the entity, Yakima River metapopulation, and the attribute was defined as no decline to a subpopulation or the overall metapopulation. In this manner, we addressed the management objective of no net loss of Chinook salmon, an iconic and protected species. Climate change-induced changes in water quality parameters (temperature and dissolved oxygen levels) used models based on projected climatic conditions in the 2050s and 2080s by the use of a probabilistic model. Pesticide concentrations in the original model were modified assuming different scenarios of pest control strategies in the future, because climate change may alter pest numbers and species. Our results predict that future direct and indirect changes to the YRB will result in a greater probability that the salmon population will continue to fail to meet the management objective of no net loss. As indicated by the sensitivity analysis, the key driver in salmon population risk was found to be current and future changes in temperature and dissolved oxygen, with pesticide concentrations being not as important. Integr Environ Assess Manag 2024;20:419-432. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Biochemical and Quality Parameter Changes of Wheat Grains during One-Year Storage under Different Storage Conditions

The selection of suitable storage conditions and monitoring of changes in the wheat grains using suitable parameters are of great importance for the sustainability of technological quality and utilization of the entire stored quantity of wheat grains without waste generation until the next harvest. Wheat grains of three varieties, stored for 12 months at three different conditions of environmental temperature and relative humidity (% RH): (1) 40 ± 1.06 °C; 45 ± 3% RH; (2) 4 ± 1.05 °C; 45 ± 4% RH, (3) 15 ± 8.51 °C; and 67 ± 4% RH, were compared for germination percentage, protein and advanced glycation end products content, oxidoreductive and proteolytic enzyme activity, wet gluten content and falling number. A decrease in the activity of guaiacol peroxidase and polyphenol oxidase, as well as an increase in the content of advanced glycosylation end products and the falling number, was observed in wheat grains during storage conditions at 40 ± 1.06 °C; 45 ± 4% RH. On the other hand, storage of wheat grains at lower temperatures resulted in much lower changes in examined parameters, among which advanced glycation end-product content, peroxidase activity and falling number values were the greatest. Based on the obtained results, it can be assumed that changes in guaiacol peroxidase activity and falling number might be used as indicators of improper wheat grain storage.

Analysis of water quality and trophic status of reservoirs in Chuzhou City, China

AbstractReservoir is a vital tool for human utilization of water resources, and the deterioration of its water quality can seriously threaten the water cycle and sustainable urban development. However, there are relatively few studies in academia that analyse and evaluate the water quality of multiple reservoirs at the same time. To address this knowledge deficit, we collected 108 water samples from three different reservoirs in Chuzhou City for 36 months (from 2019 to 2021), explored the drivers of changes in water quality parameters over time and the extent of eutrophication. Our results indicated that the water quality of the reservoirs was deteriorating during the study period, among which Huanglishu Reservoir and Shahe Reservoir reached mild eutrophic status, and both had higher eutrophication levels than Chengxi Reservoir. Secchi depth, total nitrogen and total phosphorus were the principal factors inducing eutrophication. The biassed utilization of reservoir functions was the major contributor to the discrepancy in the degree of eutrophication. Furthermore, Pearson correlation analysis revealed that there are significant correlations between many water quality parameters. Cluster analysis grouped the 12 months of each year into three clusters (stable water level period, rainy season high flow period and winter low flow period). Based on this, analysis of variance showed that most water quality parameters varied considerably between the clusters. Collectively, this study identified the actual water quality conditions of three reservoirs in Chuzhou City and provided guidance for local water quality management and environmental protection.

Improved postharvest quality attributes of sweet and sour cherry by using low pressure UVC versus light-emitting diodes (LEDs)

The aim of this study was to evaluate the effects of LPUVC253.7 nm and LEDs405.5 nm light on sweet and sour cherries, to assess the potential of post-harvest illumination for fruit shelf-life and quality extension. Fresh cherries were treated at several doses (up to 1.56 kJ m−2) in a lab design chamber. Microbiological parameters, total phenolic content, antioxidant activity, and quality properties such as weight loss, color, pH, and total soluble solids content, were assessed before and after illumination and during storage time up to 24 days at 4 and 25 °C. Studies on inactivation of natural fruit microbiota and artificially inoculated potential spoilage bacteria Pseudomonas syringae and Aureobasidium pullulans were performed. A maximum reduction of 1.89 and 1.66 log on total aerobic mesophilic bacteria and total mold and yeasts was obtained after light illumination at 253.7 nm on spiked cherry fruits. Regarding fruit quality properties, both light (LPUVC253.7 nm and LEDs405.5 nm) illumination caused no change (p > 0.05) in quality parameters compared with non-treated fruits.Industrial relevance: There is an increasing global demand from consumers for agricultural products high nutritional quality with no or minimal chemical preservatives. Postharvest physical ultraviolet-C (UVC) treatment before or during cold storage can inactivate microbial contaminants, alleviate low-temperature damage, reduce postharvest decay, and extend shelf life of fruits while improving chemical safety. The present study indicated that post-harvest LPUVC and LEDs illumination of cherries can be used as a clean and environmental forthcoming process to extend the shelf-life of fruits with highly preserved quality.

What drives the changing characteristics of phytoplankton in urban lakes: Climate, hydrology, or human disturbance?

Phytoplankton in shallow urban lakes are influenced by various environmental factors. However, the long-term coupling effects and impact pathways of these environmental variables on phytoplankton remain unclear. This is an emerging issue due to high urbanization and the resultant complex climate, lake hydrology and morphology, human interference, and water quality parameter changes. This study used Tangxun Lake, the largest urban lake in the Yangtze River Economic Belt, as an example to assess for the first time the individual contributions and coupled effects of four environmental variables and fourteen indicators on chlorophyll-a (Chla) concentrations under two scenarios from 2000 to 2019. Additionally, the influence pathways between the environmental variables and Chla concentration were quantified. The results indicated that the Chla concentration was most affected by lake hydrology and morphology, as were the total nitrogen, total phosphorus, and transparency. Especially after urbanization (2015–2019), the coupling effect of human interference, lake hydrology and morphology, and water quality parameters was strongest (18%). This is mainly due to fluctuations in the lake water level and an increase in the shape index of lake morphology, large amounts of nutrients were input, which reduced lake transparency and indirectly changed the Chla content. In addition, due to the rapid development of Wuhan city, the expansion of construction land has led to an increase in impervious surface area and a decrease in lake area. During periods of intense summer rainfall, a substantial amount of pollutants entered the lakes through surface runoff, resulting in decreased lake transparency, and elevated concentrations of nitrogen and phosphorus, indirectly increasing the Chla content. This study provides a scientific basis for aquatic ecological assessment and pollution control in urban shallow lakes.

The effectiveness of using probiotics, their effect on growth and chemical composition of broiler chicken meat

The article illustrates the effect of low-quality feed on growth of broiler chickens, as well as on quality parameters of meat. The production of economical and environmentally quality poultry products has an importance role on ensuring the country’s food security. the need for the Development of alternative drugs and their implementation in veterinary practice is increasing because developed countries are abandoning the use of chemicals and antibiotics. The important role plays using of biologically active additives created in recent years, especially new generation probiotics. In our research determined the advantage influence of probiotic consisting of several living bacteria, on physiological processes in the body of broiler chickens, as well as a significant change in quality parameters of meat. Poultry meat differ from other animals’ meat with chemical characteristics and easy digestibility on human organism and considers like a best source of important nutrients.

Comparative changes in quality parameters and nutrient ‎composition in healthy and creased fruit, and the ‎effectiveness of moringa leaf extract in reducing creasing ‎incidence of Washington navel orange (Citrus Sinensis L. ‎Osbeck)‎

Comparative changes in quality parameters and nutrient ‎composition in healthy and creased fruit, and the ‎effectiveness of moringa leaf extract in reducing creasing ‎incidence of Washington navel orange (Citrus Sinensis L. ‎Osbeck)‎

Changes in Runner Peanut Quality Parameters as a Function of Roast Times

Physical and chemical changes in runner peanuts were evaluated after roasting for various times up to 24 minutes. The seed size, color, moisture content, total oil content, sugar content, free amino acid content and flavor attributes were determined on raw and roasted peanuts from each subsample. Moisture declined from 6.5 % to 0.4 % (DW) after 24-min. Drying curves were constructed and the critical moisture content (CMC=2.41 % (DW)) was determined at 6-min. Roast peanutty rose rapidly between 6- and 12-min of roasting followed by a steep decline. Other sensory descriptors exhibited changes in their response curves at 6- and 12- min. Color analysis showed that kernels and pastes darkened (L values) during roasting and became redder (a value) and yellower (b value). Nearly all amino acids, sucrose and stachyose concentrations dropped rapidly after 6-min. Sensory, color, sugars, and amino acid data plotted against time and moisture content exhibited specific patterns with threshold points, maxima and inflection points occurring at the same times and moisture contents. The data were discussed in terms of developing a more mechanistic view of the roasting process. Proper roasting is required for everything from genotype evaluation to mass product production. A more complete understanding of the physical and chemical effects of roasting times can guide practices to better optimize peanut quality.

Study of the Kinetics of Adhesive Bond Formation Using the Ultrasonic Method

Adhesive bonding is widely used in modern industry. It has many advantages—the main one being the reduction in production costs. It also has certain limitations. One of the limitations of adhesive bonds is the relatively long bonding time of the joints. The main objective of this research was to determine the possibility of studying the kinetics of adhesive bond formation using a non-destructive ultrasonic method. A research experiment was planned and carried out. Adhesive specimens were prepared, and their quality changes over time were evaluated. In addition, the change in ultrasonic measures during the testing of these bonds was evaluated, as well as the hardness of the adhesive. In this study, the choice of test apparatus was made, in particular ultrasonic probes for the adhesive used and the materials to be bonded. The choice of adhesive was also made, for one in which bonding phenomena occur uniformly throughout the volume. This work examined the changes in the mechanical strength and hardness with time. The tests showed that the greatest changes in mechanical strength occur within the first 24 h after the bond was made. With the mechanical strength reaching 12.6 Mpa after 216 h, the strength in the first 24 h was 10.36 (for bonded steel sheets). For bonded steel discs, the maximum tensile strength was 26.99 Mpa (after 216 h), with a hardness of 22.93 Mpa during the first 24 h. Also, significant changes were observed in the adhesive hardness during the first 24 h. The hardness of the adhesive after 216 h was 70.4 Shore’a on the D scale, while after 24 h it was 69.4 Shore’a on the D scale. Changes in the ultrasonic parameters of the adhesive bond quality were found to occur along with changes in the bond quality.

Developing a predictive model of salted kimchi cabbage shelf-life using the general stability index

Salted kimchi cabbage (SKC) is a ready-to-use product used to manufacture kimchi. However, during distribution and storage, deterioration in quality parameters, such as pH, total titratable acidity, aerobic plate count, and color, lowers the product value. To ensure sufficient distribution and consumer storage, SKC should be vacuum-packed and cold-stored. Therefore, in this study, changes in SKC quality parameters were monitored at different cold storages (≤10 °C), and a predictive model of SKC shelf life was established using the general stability index (GSI) method. The established GSI method is an adequate tool for predicting the shelf life of SKC. The model with the highest R2 value was obtained by fitting the data with a second-order equation and integrating it with 0–10 °C using the Arrhenius equation. This study provides important insights into the quality assessment and shelf-life prediction of SKC during cold storage, contributing toward quality management systems. In addition, chromaticity values, which previously lacked reproducible measurement methods for SKC, were obtained after segmenting complex-shaped parts using a novel image analysis technique. This technique can be applied to a variety of vegetables to determine chromaticity of individual parts for assessing quality based on symptoms like browning.

Non-thermal processing of watermelon and red grape juices in thin-profile continuous-flow pulsed UV light reactors: Effect on microbiological safety and nutritional value

Herein, we report successful non-thermal pasteurization of fruit juices (watermelon and red grape juices) in a flow-through pulsed light (PL) reactor. Impact of PL reactor configuration (annular/coiled tube), product flow rates (14–75 L/h) and pulse frequency (1–5 Hz) on the inactivation of Escherichia coli ATCC 29055, Listeria innocua ATCC 33090, and Clostridium sporogenes ATCC 7955 in red grape (pH = 3.37) and watermelon juice (pH = 5.02), and changes in quality and nutritional parameters, was explored. >5 and > 7 log10 microbial reductions were achieved in annular and coiled reactor respectively, demonstrating PL's potential in juice pasteurization. Watermelon juice exhibited higher microbial inactivation, while E. coli was found to be most susceptible. The inactivation kinetics using three different models were compared wherein ‘log-linear plus tail model’ showed the best fit. During PL processing, there were minor changes in pH and colour of both juices, whereas nutritional parameters (total anthocyanins, total phenolics, antioxidant capacity, vitamin C, trans-resveratrol, and lycopene content) decreased significantly (p < 0.05) by up to 39.1%, 62.2%, 53.8%, ∼70%, 82%, and 46.8%, respectively, yet at levels lower than conventional thermal pasteurization. These results shall inspire commercialization of PL based fruit beverage pasteurization systems.

Contrasting immediate impact of prescribed fires and experimental summer fires on soil organic matter quality and microbial properties in the forest floor and mineral soil in Mediterranean black pine forest

Prescribed fire (PB) is used to achieve ecological objectives and to reduce fuel hazard thus limiting detrimental impacts of wildfire and appropriate selection of prescription window is critical for these goals. Operational use of PB in the Mediterranean forest is scarce and information about its effects on soil remains incomplete. This study for the first time i) compared the immediate impact of spring and autumn PB and experimental summer fire on key properties of forest floor and mineral topsoil in Mediterranean black pine forest, and ii) assessed the capacity of PB to reduce fuel, with limited immediate impacts on soil. PB significantly reduced the 32.5 % of pre-fire forest floor depth, while summer fire consumed 88.5 % and exposed about 30 % of the mineral soil surface. Mean maximum temperature during fire at the mineral soil surface was 23 °C in PB, in contrast to 128 °C in summer fire, while soil heating at 2 cm depth was negligible in both cases. PB did not cause immediate changes in OM quality parameters, and chemical (C and N concentrations, C/N and pH) and microbiological properties (Cmic, Cmic/C, and β-glucosidase, acid phosphatase and alkaline phosphatase activities) in forest floor or mineral topsoil (0–2 cm). By contrast, summer fire greatly increased OM recalcitrance and reduced Cmic, Cmic/C and enzyme activities in forest floor immediately after fire. In the mineral topsoil, only microbial properties were significantly reduced. The maximum temperature reached during fire in forest floor and topsoil was associated with most of the overall changes in properties in both layers. The findings suggest that prescribed fire can significantly reduce fuel with limited initial impacts on soil. Although these findings are encouraging for operational use of prescribed burning in the ecosystem under study, long-term monitoring of repeated application of the technique on soil properties and other ecosystem components is necessary.

Lac dye-based intelligent colorimetric indicator for real-time freshness monitoring of packaged white button mushrooms (Agaricus bisporus)

The study aimed to develop an intelligent real-time freshness indicator for white button mushrooms by immobilizing the lac dye, a natural anthraquinone dye on filter paper. The indicator was characterized for its pH responsiveness; structural, mechanical, thermal properties; and color stability. During the freshness test, mushrooms were packed in punnet with an indicator placed in the package headspace and stored at two different temperatures (4 °C and 25 °C). Mushroom spoilage was monitored concurrently by indicator's color change, physicochemical indices, and volatile organic compounds (VOC) generated during storage. The FTIR results revealed that dye was immobilized on matrix via hydrogen bonding. A slight reduction in matrix crystallinity post dye immobilization was observed. However, the thermal and mechanical properties remained unaffected. Indicator showed good color stability during one month storage at 4 °C and 25 °C. The indicator changed its color from orange-red (at acidic pH) to purple (at alkaline pH) due to the inherent properties of lac dye. In the freshness test, the visual color change of indicator distinguished mushrooms into three stages: ' fresh', 'medium fresh', and 'spoiled'. Principle Component Analysis (PCA) validated the synchronization between color change of indicator and quality parameters. Partial Least Square (PLS) regression models derived from indicator's color parameter data successfully predicted the physicochemical indices of mushrooms stored at 4 °C. The lac dye-based indicators emerged as a novel and potential solution for non-destructive freshness monitoring of white button mushrooms.

Use of dill extracts as a natural preservative on shelf‐life extension of rainbow trout croquettes during refrigerator storage

AbstractIn this study, changes in quality parameters of rainbow trout croquettes treated with dill extracts obtained by brewing (BDA) and distillation (DDA) methods were investigated during 61 days of refrigerated storage (+2 ± 1°C). Physicochemical, microbial, and sensory parameters of the rainbow trout croquettes were analyzed once every 4 days. It was observed that the precooking process and additives influenced the nutrient composition and color change of the croquettes. Total volatile base nitrogen and thiobarbituric acid values did not exceed the limit values in any group during refrigerated storage and these values were found as 23.10 ± 0.89 mg/100 g and 3.13 ± 0.08 mg MDA/kg in the control group (C), 21.00 ± 0.92 mg/100 g and 2.77 ± 0.14 mg MDA/kg in BDA group, and 21.70 ± 0.92 mg/100 g and 2.85 ± 0.07 mg MDA/kg in DDA group, respectively. Extract treatments, especially DDA, resulted in a significant reduction in the counts of total aerobic mesophilic and psychotropic bacteria in trout croquettes compared to the control group. It was determined that the sensory scores of all croquette groups decreased during storage and the acceptability scores of the C, BDA, and DDA groups reached on the 33rd, 57th, and 61st days of storage, respectively. According to the results, this work demonstrated that the dill extracts both distilled and brewed can be used as a natural additive to improve the quality and extend the shelf life of rainbow trout croquettes.