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The surveillance and assessment of the total viable count (TVC) of Staphylococcus under different levels of catheter contamination are crucial for the prevention and evaluation of catheter‐related infections in hemodialysis (HD). This paper demonstrates the noninvasive and accurate measurement of the TVC of Staphylococcus using wavelength‐modulated tunable diode laser absorption spectroscopy (WMAS). The tunable distributed feedback laser with a central wavelength of 2004 nm was employed and the detection limit of 22.5 ppm for carbon dioxide (CO2) produced by Staphylococcus epidermidis was obtained. The growth of Staphylococcus under different medium concentrations was studied, and the results indicated a strong correlation between the growth rate and final TVC of S. epidermidis with the medium concentration. When the degree of catheter contamination was low, resulting in minimal residual nutrient concentration within the catheter, the bacterial growth rate and TVC were effectively suppressed. Therefore, it is proven that WMAS is a user‐friendly, noninvasive, and high signal‐to‐noise ratio technique for monitoring Staphylococcus, making it an effective tool for assessing Staphylococcus growth in HD catheter surveillance. [ABSTRACT FROM AUTHOR]

The popular method of micro-respirometry (μR) for measuring total viable (aerobic) count (TVC) utilises luminescence-based O2 sensors that are difficult to fabricate and therefore expensive. A simple method is described for making inexpensive, ink-based potential substitutes that utilise the same O2-sensitive dyes. The sensitivity of such inks is readily increased by using dyes with a long lifetime in the absence of O2, τo, and/or an ink resin/polymer with a high O2 permeability, Pm(O2). Response modelling of the μR-based TVC system and subsequent testing using a range of O2 sensors of different sensitivity show that there is little to be gained by making the O2 sensor either very sensitive or insensitive, and that the best O2 sensors are dyes such as Pt(II) tetraphenyltetrabenzoporphyrin (PtBP), with τo = ca. 40–50 μs. Further work shows that a simple-to-make PtBP ink can be used as a direct replacement for the expensive O2 sensor used in commercial instruments for measuring TVC based on μR. In addition, the PtBP can be replaced by an even less expensive O2-sensitive dye, Pt(II) meso-tetra(pentafluorophenyl)porphyrin (PtTFPP). The potential use of inexpensive O2-sensitive inks as an alternative to any expensive commercial counterpart based on the same O2-sensitive dye is discussed briefly. [ABSTRACT FROM AUTHOR]

Controlled freezing point storage assisted by the electrostatic field has been proven to maintain the quality of fresh meat effectively. In this study, we evaluated the freshness variation of pork under controlled freezing point storage assisted by different high-voltage electrostatic field (HVEF) usage frequencies, including single-used HVEF (SHVEF), interval-used HVEF (IHVEF), and continuous-used HVEF (CHVEF). The pH value, total volatile basic nitrogen (TVB-N), total viable count (TVC), and bacterial community composition were determined. The results showed that the pH value in the three groups gradually decreased, while the TVB-N and TVC increased along with the growth of bacteria. The IHVEF and CHVEF treatments effectively delayed the decrease in pH value and significantly reduced the overall level of TVC and TVB-N in fresh pork at a later storage period. Bacterial community composition analysis showed that the dominant bacteria in all three treatments were Pseudomonas, Latilactobacillus, and Brochothrix, and HVEF treatment can significantly decrease their diversity and abundance. The functional analysis showed that HVEF treatment has influenced the pathways of amino acid metabolism, carbohydrate metabolism, and energy metabolism during controlled freezing point storage. In conclusion, the HVEF treatment has a significant (p < 0.05) inhibitory effect against dominant bacteria and enhanced the storage quality of fresh pork. These results could provide theoretical guidance for the possible application of HVEF technology in controlled freezing point preservation of meat. [ABSTRACT FROM AUTHOR]

The popular method of micro-respirometry (μR) for measuring total viable (aerobic) count (TVC) utilises luminescence-based O2 sensors that are difficult to fabricate and therefore expensive. A simple method is described for making inexpensive, ink-based potential substitutes that utilise the same O2-sensitive dyes. The sensitivity of such inks is readily increased by using dyes with a long lifetime in the absence of O2, τo, and/or an ink resin/polymer with a high O2 permeability, Pm(O2). Response modelling of the μR-based TVC system and subsequent testing using a range of O2 sensors of different sensitivity show that there is little to be gained by making the O2 sensor either very sensitive or insensitive, and that the best O2 sensors are dyes such as Pt(II) tetraphenyltetrabenzoporphyrin (PtBP), with τo = ca. 40–50 μs. Further work shows that a simple-to-make PtBP ink can be used as a direct replacement for the expensive O2 sensor used in commercial instruments for measuring TVC based on μR. In addition, the PtBP can be replaced by an even less expensive O2-sensitive dye, Pt(II) meso-tetra(pentafluorophenyl)porphyrin (PtTFPP). The potential use of inexpensive O2-sensitive inks as an alternative to any expensive commercial counterpart based on the same O2-sensitive dye is discussed briefly.

The aim of this study was to compare the microbiological quality of cooked sausages produced with a traditional salt content (2.1%) and reformulated batches with a salt content reduced to 1.7%. The reformulation was tested on two types of comminuted meat products – Špekáčky sausage with a diameter of up to 46 mm or Bologna-type sausages in diameter of 85 mm (Gothaj sausage) or 75 mm (Junior sausage). The total viable count (TVC) increased only slightly during the four-week storage (4 ± 1 °C) of all batches of Špekáčky sausage. Comparing batches 1.7 and 2.1, there is an evident difference in the number of CFU/g, with samples of Špekáčky 1.7 showing numbers of bacteria higher by approximately 1 logarithmic order throughout practically the entire storage period (P = 0.001). The population of lactic acid bacteria (LAB) remained well beneath a value of 5.0 log CFU/g even at the end of the experiment. For Bologna-type sausages, the TVC was either beneath the limit of detection or at its boundary in all samples. LAB were not detected during storage of Bologna-type sausages. The results confirmed that the proportion of salt in cooked sausages can be reduced to 1.7% without negatively affecting the shelf life or safety of the final products. [ABSTRACT FROM AUTHOR]

The total viable count (TVC) of bacteria is an important index to evaluate the freshness and safety of dishes. To improve the accuracy and robustness of spectroscopic detection of total viable bacteria count in a complex system, a new method based on a near-infrared (NIR) hyperspectral hybrid model and Support Vector Machine (SVM) algorithms was developed to directly determine the total viable count in intact beef dish samples in this study. Diffuse reflectance data of intact and crushed samples were tested by NIR hyperspectral and processed using Multiplicative Scattering Correction (MSC) and Competitive Adaptive Reweighted Sampling (CARS). Kennard–Stone (KS) and Samples Set Partitioning Based on Joint X-Y Distance (SPXY) algorithms were used to select the optimal number of standard samples transferred by the model combined with root mean square error. The crushed samples were transferred into the complete samples prediction model through the Direct Standardization (DS) algorithm. The spectral hybrid model of crushed samples and full samples was established. The results showed that the Determination Coefficient of Calibration ( R P 2 ) value of the total samples prediction set increased from 0.5088 to 0.8068, and the value of the Root Mean Square Error of Prediction (RMSEP) decreased from 0.2454 to 0.1691 log10 CFU/g. After establishing the hybrid model, the RMSEP value decreased by 9.23% more than before, and the values of Relative Percent Deviation (RPD) and Reaction Error Relation (RER) increased by 12.12% and 10.09, respectively. The results of this study showed that TVC instewed beef samples can be non-destructively determined based on the DS model transfer method combined with the hybrid model strategy. This study provided a reference for solving the problem of poor accuracy and reliability of prediction models in heterogeneous samples. [ABSTRACT FROM AUTHOR]

Milk beverage with added natural sweetener is well appreciated by consumers as a nutritious and healthy product with unique sensorial quality attributes. However, this product requires a suitable pasteurization method without significant impact on the sensorial and physicochemical quality characteristics of the product. This study optimizes the pulsed electric filed (PEF) conditions for the pasteurization of a milk-date beverage with conserved physicochemical quality properties. The effect of process variables, such as pulse off time (20, 30, and 40 μs), number of pulses (20, 50, and 80), powder ratio (10, 15, 20, and 25% w/w), storage time (2, 4, and 6 days), and storage temperature (5, 15, and 25 °C) on the responses of total viable count (TVC), color difference (∆E), pH, and total soluble solids (TSS) was evaluated using the RSM central composite design (CCD). Pulse off time, number of pulses, date powder/milk ratio (w/w), storage time, and storage temperature greatly impacted the microbial and physical properties of the beverage. The optimal conditions for decreasing the microbiological load and physical change of beverages were a pulse off time of 40 μs, number of pulses of 80, and storage temperature of 5 °C for all powder ratios. These variables gave a safe beverage for up to six days. At optimal conditions, the values of pH, TSS, ∆E, and TVC were 7.51, 15.44 °Brix, 18.01, and 0.138 Log 10 CFU/mL, respectively, for the powder ratio of 10% (w/w); 7.66, 18.6 °Brix, 21.46, and 0.284 Log 10 CFU/mL, respectively, for the powder ratio of 15% (w/w); 7.56, 21.52 °Brix, 25.24, and 0.577 Log 10 CFU/mL, respectively, for the powder ratio of 20% (w/w); and 7.2, 24.2 °Brix, 29.34, and 0.741 Log 10 CFU/mL, respectively, for the powder ratio of 25% (w/w). [ABSTRACT FROM AUTHOR]

[Objectives]The paper aimed to investigate the feasibility of growth simulation of the microorganisms in chilled meat by the E-nose and hyperspectral imaging techniques (HSI). [Methods]The total viable count of the chilled beef stored at 4 ℃ was determined by the plate count method, and the E-nose and HSI data were collected. And the Huang model and Baranyi model obtained from the plate count method, E-nose and HSI information were compared. [Results]The growth models based on the traditional plate count method were highly accurate, with the model coefficient of determination (R-2) of 0.993. Compared with the plate count method, growth models constructed by Method ⅰ and ⅱ based on E-nose feature information were slightly less accurate, with R-2 greater than 0.871 and correlation coefficients (r) of 0.917-0.994 between them. The model established by Method Ⅰ based on HSI had a comparable R-2,with r of 0.998. Whereas the model based on hyperspectral values (Method Ⅱ) performed slightly worse, with R-2 of 0.749-0.918 and r of 0.761-0.859. [Conclusions]The information of E-nose and HSI could be used to simulate the growth of microorganisms in chilled beef, which provided theoretical support and technical reference for the application of non-destructive testing techniques in predictive microbiology. [ABSTRACT FROM AUTHOR]

An affordable and sustainable tertiary treatment is imperative to solve the secondary contamination issues related to wastewater reuse. To decontaminate and disinfect the actual secondary treated wastewater, various types of advanced oxidation processes (AOPs) have been studied. The optimization of the oxidant and catalyst is carried out to identify the best-performing system. Under selected experimental conditions, UV/peroxymonosulfate (PMS), O3/PMS, UV/MnO2, O3/MnO2, UV/O3/H2O2, O3/MnO2/H2O2, UV/MnO2/H2O2, and UV/O3/MnO2 has been identified as an efficient treatment option for simultaneous decontamination (>90% COD removal) and disinfection (100% inactivation of the total viable count of bacteria). The techno-economic assessment revealed that UV/MnO2 (23.5 $ kg−1 of COD) UV/O3/MnO2 (37.4 $ kg−1 of COD), UV/H2O2/MnO2 (36.4 $ kg−1 of COD), and O3/MnO2/H2O2 (32.5 $ kg−1 of COD) are comparatively low-cost treatment processes. Overall, UV/MnO2, UV/H2O2/MnO2, and O3/MnO2/H2O2 are the three best treatments. Nevertheless, further investigation on by-product and catalyst toxicity/recovery is needed. The results showed that AOPs are a technologically feasible treatment for simultaneously removing persistent organic pollutants and pathogens from secondary treated wastewater. HIGHLIGHTS Simultaneous removal of pathogens and organic contaminants is essential to recycling wastewater.; Advanced oxidation processes are cost-effective tertiary treatment.; Photocatalysis offered complete removal of pathogens and ∼90% removal of chemical oxygen demand (COD) within a short reaction time.; Inactivation of bacteria is better in the peroxymonosulfate system.; Photocatalytic ozonation was a cost-effective treatment for COD removal.;

The total viable count (TVC) of bacteria is an important index to evaluate the freshness and safety of dishes. To improve the accuracy and robustness of spectroscopic detection of total viable bacteria count in a complex system, a new method based on a near-infrared (NIR) hyperspectral hybrid model and Support Vector Machine (SVM) algorithms was developed to directly determine the total viable count in intact beef dish samples in this study. Diffuse reflectance data of intact and crushed samples were tested by NIR hyperspectral and processed using Multiplicative Scattering Correction (MSC) and Competitive Adaptive Reweighted Sampling (CARS). Kennard–Stone (KS) and Samples Set Partitioning Based on Joint X-Y Distance (SPXY) algorithms were used to select the optimal number of standard samples transferred by the model combined with root mean square error. The crushed samples were transferred into the complete samples prediction model through the Direct Standardization (DS) algorithm. The spectral hybrid model of crushed samples and full samples was established. The results showed that the Determination Coefficient of Calibration (RP2) value of the total samples prediction set increased from 0.5088 to 0.8068, and the value of the Root Mean Square Error of Prediction (RMSEP) decreased from 0.2454 to 0.1691 log10 CFU/g. After establishing the hybrid model, the RMSEP value decreased by 9.23% more than before, and the values of Relative Percent Deviation (RPD) and Reaction Error Relation (RER) increased by 12.12% and 10.09, respectively. The results of this study showed that TVC instewed beef samples can be non-destructively determined based on the DS model transfer method combined with the hybrid model strategy. This study provided a reference for solving the problem of poor accuracy and reliability of prediction models in heterogeneous samples.

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The demand for non-cow milk and the products derived from it, is constantly increasing; thus, correct and effective pasteurization becomes necessary. Typical practices for evaluating milk pasteurization are mainly based on the thermal inactivation of an endogenous enzyme, alkaline phosphatase (ALP). The ALP tests, originally designed and applied to pasteurized cow milk, are often used to control pasteurization in non-cow milk, without sufficient data on their suitability; EFSA calls on the scientific world for collecting more information on the subject. In this study, the pertinent details of the ALP assay for non-cow milk products are summarized, and a comparison is performed regarding the evaluation of the adequacy of commercially available tests for the determination of ALP activity in non-cow milk. At the same time, raw and pasteurized non-cow milk was analyzed microbiologically using standard ISO methods and MALDI-TOF MS in order to confirm the thermal effect on common microorganisms. In these preliminary results, various ALP tests do not appear to be fully reliable as indicators for the pasteurization of some types of non-cow milk such as camel and donkey milk or even goat and sheep milk, using the EFSA proposed limits. ALP commercial kits may not be suitable as pasteurization indicators for various types on non-cow milk, and alternatives should be investigated. [ABSTRACT FROM AUTHOR]

In the last twenty years, the number of publications presenting generalized pH-sensitive devices proposed for food freshness monitoring has been steadily growing, but to date, none of them have succeeded in exiting the laboratory and reaching the supermarket shelf. To reach this scope, we developed a large-scale applicable pH-sensitive sensor array to monitor perishable foods' degradation. We ensured freshness monitoring in domestic conditions, using sales packages and during chilled storage, by simple naked-eye readout and multivariate imaging analysis, and we fully corroborated the device by (i) projection of unknown independent samples in the PCA model, (ii) TVB-N quantification and (iii) microbiological assay. The choice of commercial and cheap dye and polymeric support already employed in food packaging ensures the low-cost and scalability of the device and the promising results obtained make this device an eligible candidate for large-scale implementation. [ABSTRACT FROM AUTHOR]

The Barhi date is a high-quality date cultivar whose fruits (dates) are plucked and eaten fresh when they reach the Khalal maturity stage due to their sweetness, crispiness, and yellow skin color. After harvesting, Khalal Barhi fruits rapidly matured to the Rutab stage, where their tissues become soft and their skin color browner. This results in a decrease in their market value and customer demand. This study aims at investigating the effectiveness of the postharvest ultrasonic treatment in conserving the physical, microbial, and nutritional quality of Barhi fruits and extending their shelf life. To achieve the goals of the present work, the response surface methodology (RSM) was used for the optimization of the ultrasonic intensity (50, 100, 150, and 200 W/cm2) and application time (5, 10, 15, and 20 min) to preserve the Barhi dates high quality features for varied storage temperatures (1, 5, 15, and 25 °C) and duration (1, 6, 16, and 21 days). In RSM, a four-factors-mixed-levels central composite rotatable design (CCRD) was applied to optimize the ultrasound treatment and storage environments for better-quality physical [total soluble solids (TSS), firmness, and total color changes (ΔE)], microbial [total viable count (TVC)], nutritional [total phenolic content (TPC), DPPH antiradical activity, glucose, and fructose] features of Barhi dates. The outcomes showed that ultrasound intensity and its application time, storage temperature, and storage period influence the physical, microbial, and nutritional quality attributes in different magnitudes. The ideal settings for lessening the changes in the physical attributes, eliminating the microbial growth, and improving the nutritional quality attributes were 140 W/cm2, 5.2 min, 20.9 °C, and 21 days for ultrasound intensity, ultrasound exposure duration, storage temperature, and storage duration, respectively. In conclusion, this study proved the potential application of ultrasound for persevering the excellence aspects of Barhi dates and identified the ideal ultrasound environments for maintaining the physical, microbial, and nutritional quality features of Barhi dates during extended storing. [ABSTRACT FROM AUTHOR]

Defined as the mammary glands/udder inflammation, mastitis caused by various infectious etiological agents, is still considered a debilitating condition in dairy cows, influencing both animal welfare and the dairy industry through decreased production performance and increased culling rates. The consumption of raw milk or other milk products is related to the microbiological quality of raw milk. The main disadvantages in applying laboratory microbiological culture are related to logistical limitations and the expense of shipping samples, as well as the time required for analysis to receive interpretations, which can range from three to five days. The aim of this study is to validate the Soleris System as a rapid alternative method to the plate-count method in order to assess the microbiological quality of raw milk. Thus, this study establishes the reliability of this alternative method for determining the total viable count in raw milk in samples from cows. In conclusion, raw milk evaluation using the Soleris System demonstrates its promise as a valid tool for accurate testing in the dairy industry.

Defined as the mammary glands/udder inflammation, mastitis caused by various infectious etiological agents, is still considered a debilitating condition in dairy cows, influencing both animal welfare and the dairy industry through decreased production performance and increased culling rates. The consumption of raw milk or other milk products is related to the microbiological quality of raw milk. The main disadvantages in applying laboratory microbiological culture are related to logistical limitations and the expense of shipping samples, as well as the time required for analysis to receive interpretations, which can range from three to five days. The aim of this study is to validate the Soleris System as a rapid alternative method to the plate-count method in order to assess the microbiological quality of raw milk. Thus, this study establishes the reliability of this alternative method for determining the total viable count in raw milk in samples from cows. In conclusion, raw milk evaluation using the Soleris System demonstrates its promise as a valid tool for accurate testing in the dairy industry. [ABSTRACT FROM AUTHOR]

The objective of the study was to determine the effect of freezing broiler neck skin samples before their microbial analysis, compared to freshly examined samples regarding total viable count (TVC) and Enterobacteriaceae count (EC). For this, 300 neck skin samples were taken at a German commercial broiler abattoir and each neck skin sample was cut into two parts. One randomly selected part underwent microbial examination after storage at 4 °C overnight; the other part was frozen at −30 °C for eight weeks before analysis in the same laboratory. Log cfu/g values of TVC and EC were separately compared between the fresh and frozen neck skin samples. A difference up to 0.5 log values was set as acceptable, i.e., fresh and frozen samples with counts that differed by this amount were considered as not different. The differences between the grouped samples of fresh and frozen broiler neck skin regarding both TVC and EC levels were less than 0.5 log values. Thus, it can be assumed that broiler neck skin samples, both fresh and frozen for eight weeks, are suitable for microbiological examination, as the TVC and EC results showed equivalence. Therefore, freezing broiler neck skin samples can be an option to maintain viable bacteria levels in broiler neck skin samples taken for microbiological examination in process control, when freezing and later examination is necessary due to insufficient laboratory capacity for the examination of fresh neck skin samples. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the effect of chitosan on the pre-servation of Macrobrachium rosenbergii during cold storage. M. rosenbergii samples were divided into control and experimental groups and immersed in pure water and 1.5% chitosan solutions, respectively, followed by storage at 4°C Changes were measured in tissue sensory scores, pH (hydrogen potential), total volatile base nitrogen (TVB-N), total viable count (TVC), and K values. Further, 16S ribosomal ribonucleic acid (rRNA) sequencing was used to study the effects of chitosan on microbial diversity within prawns across storage times. Treating M. rosenbergii with chitosan inhibited increases in TVB-N, TVC, and K values of prawns, thereby extending prawn meat shelf life by two to three days. During storage, Lactococcus and Candidatus Hepatoplasma became the dominant spoilage bacteria of M. rosenbergii bacterial communities. The abundance of Lactococcus in the experimental M. rosenbergii samples was as high as 69.84% during the late storage stage, while the abundance of Candidatus Hepatoplasma in the control group was as high as 46.88% in the middle storage stage. Chitosan effectively controlled changes in the quality of M. rosenbergii meat during cold storage, altered their bacterial community structures, inhibited spoilage, and exhibited beneficial preservation effects. [ABSTRACT FROM AUTHOR]

Barhi dates are widely consumed at Khalal maturity stage and preserving the freshness quality of Barhi at this stage is a challenging task as this period is short and the fruits are more perishable. In this study, response surface methodology (RSM) was applied to optimize the infrared (IR) treatment and storage conditions for preserving the physicochemical, microbial, and bioactive attributes of fresh Barhi dates. The effect of four factors, IR temperature (50, 70, 90, and 110 °C), IR time (1, 2, 3, and 4 min), storage temperature (1, 5, 15, and 25 °C), and storage time (1, 6, 11, 16, and 21 days), on the responses of total soluble solids (TSS), hardness, total color change (ΔE), total viable count (TVC), total phenolic content (TPC), antioxidant activity (DPPH), and glucose content were evaluated following central composite design (CCD). IR temperature, IR time, storage temperature, and storage time significantly affected the physical, microbial, and bioactive attributes of Barhi dates. The optimal conditions for minimizing the physical changes and microbial load and maximizing the bioactive attributes were IR temperature of 50 °C, IR time of 1.2 min, storage temperature of 1 °C, and storage time of 20 days. At the optimum conditions, the values of TSS, hardness, ΔE, TVC, TPC, DPPH, and glucose were 37.22%, 70.17 N, 11.12, 2.9 log CFU/g, 36.1 mg GAE/g, 65.31%, and 25.38 mg/g, respectively and these values were similar to predicted values. In conclusion, this study identified the ideal IR treatment and storage conditions for maintaining the overall quality attributes of Barhi dates during prolonged storage. [ABSTRACT FROM AUTHOR]

• The influence of pulsed light on composition and microbiology was assessed. • PL upto 12 J/cm2 resulted in increase in bioactive compound composition. • PL of total fluence 24 J/cm2 led to damage of root system. • Properly selected PL resulted in microflora reduction in alfalfa sprouts. The possibility of using pulsed light (PL) pre-harvest during the cultivation of alfalfa sprouts to reduce microflora and simultaneously enhance the bioactive concentration was presented. Different fluences were compared, and the effect of PL direction on sprout quality was determined. PL application up to 12 J/cm2 per day resulted in an increased accumulation of bioactive components (vitamin C, proteins, chlorophyll, and carotenoids), in response to the stress resulting from PL emission. More interestingly, the direction of incidence was found important, with different trends observed for different bioactive components depending on whether only leaves were illuminated, or both leaves and roots were illuminated. Pulsed light directed solely towards the cotyledons (24 J/cm2) reduced the level of total microbial counts by about 0.7 log cfu/ml, and yeast and mold counts by about 1 log cfu/ml. It was found that an excessive amount of PL directed towards the roots might damage the root system, which promotes the growth of bacteria and will lower increases in the accumulation of chlorophylls, carotenoids, vitamin C, and proteins. The work will guide the development of photo-energized cultivation chambers for the production of agricultural and food products. [ABSTRACT FROM AUTHOR]

The Barhi date is a high-quality date cultivar whose fruits (dates) are plucked and eaten fresh when they reach the Khalal maturity stage due to their sweetness, crispiness, and yellow skin color. After harvesting, Khalal Barhi fruits rapidly matured to the Rutab stage, where their tissues become soft and their skin color browner. This results in a decrease in their market value and customer demand. This study aims at investigating the effectiveness of the postharvest ultrasonic treatment in conserving the physical, microbial, and nutritional quality of Barhi fruits and extending their shelf life. To achieve the goals of the present work, the response surface methodology (RSM) was used for the optimization of the ultrasonic intensity (50, 100, 150, and 200 W/cm2) and application time (5, 10, 15, and 20 min) to preserve the Barhi dates high quality features for varied storage temperatures (1, 5, 15, and 25 °C) and duration (1, 6, 16, and 21 days). In RSM, a four-factors-mixed-levels central composite rotatable design (CCRD) was applied to optimize the ultrasound treatment and storage environments for better-quality physical [total soluble solids (TSS), firmness, and total color changes (ΔE)], microbial [total viable count (TVC)], nutritional [total phenolic content (TPC), DPPH antiradical activity, glucose, and fructose] features of Barhi dates. The outcomes showed that ultrasound intensity and its application time, storage temperature, and storage period influence the physical, microbial, and nutritional quality attributes in different magnitudes. The ideal settings for lessening the changes in the physical attributes, eliminating the microbial growth, and improving the nutritional quality attributes were 140 W/cm2, 5.2 min, 20.9 °C, and 21 days for ultrasound intensity, ultrasound exposure duration, storage temperature, and storage duration, respectively. In conclusion, this study proved the potential application of ultrasound for persevering the excellence aspects of Barhi dates and identified the ideal ultrasound environments for maintaining the physical, microbial, and nutritional quality features of Barhi dates during extended storing.

The objective of the study was to determine the effect of freezing broiler neck skin samples before their microbial analysis, compared to freshly examined samples regarding total viable count (TVC) and Enterobacteriaceae count (EC). For this, 300 neck skin samples were taken at a German commercial broiler abattoir and each neck skin sample was cut into two parts. One randomly selected part underwent microbial examination after storage at 4 °C overnight; the other part was frozen at −30 °C for eight weeks before analysis in the same laboratory. Log cfu/g values of TVC and EC were separately compared between the fresh and frozen neck skin samples. A difference up to 0.5 log values was set as acceptable, i.e., fresh and frozen samples with counts that differed by this amount were considered as not different. The differences between the grouped samples of fresh and frozen broiler neck skin regarding both TVC and EC levels were less than 0.5 log values. Thus, it can be assumed that broiler neck skin samples, both fresh and frozen for eight weeks, are suitable for microbiological examination, as the TVC and EC results showed equivalence. Therefore, freezing broiler neck skin samples can be an option to maintain viable bacteria levels in broiler neck skin samples taken for microbiological examination in process control, when freezing and later examination is necessary due to insufficient laboratory capacity for the examination of fresh neck skin samples.

Barhi dates are widely consumed at Khalal maturity stage and preserving the freshness quality of Barhi at this stage is a challenging task as this period is short and the fruits are more perishable. In this study, response surface methodology (RSM) was applied to optimize the infrared (IR) treatment and storage conditions for preserving the physicochemical, microbial, and bioactive attributes of fresh Barhi dates. The effect of four factors, IR temperature (50, 70, 90, and 110 °C), IR time (1, 2, 3, and 4 min), storage temperature (1, 5, 15, and 25 °C), and storage time (1, 6, 11, 16, and 21 days), on the responses of total soluble solids (TSS), hardness, total color change (ΔE), total viable count (TVC), total phenolic content (TPC), antioxidant activity (DPPH), and glucose content were evaluated following central composite design (CCD). IR temperature, IR time, storage temperature, and storage time significantly affected the physical, microbial, and bioactive attributes of Barhi dates. The optimal conditions for minimizing the physical changes and microbial load and maximizing the bioactive attributes were IR temperature of 50 °C, IR time of 1.2 min, storage temperature of 1 °C, and storage time of 20 days. At the optimum conditions, the values of TSS, hardness, ΔE, TVC, TPC, DPPH, and glucose were 37.22%, 70.17 N, 11.12, 2.9 log CFU/g, 36.1 mg GAE/g, 65.31%, and 25.38 mg/g, respectively and these values were similar to predicted values. In conclusion, this study identified the ideal IR treatment and storage conditions for maintaining the overall quality attributes of Barhi dates during prolonged storage.

The quantification of microbes, particularly live bacteria, is of utmost importance in assessing the quality of meat products. In the context of meat processing facilities, prompt identification and removal of contaminated carcasses or surfaces is crucial to ensuring the continuous production of safe meat for human consumption. The plate count method and other traditional detection methods are not only labour-intensive but also time-consuming taking 24–48 h. In this report, we present a novel isotachophoretic quantification method utilizing two nucleic acid stains, SYTO9 and propionic iodide, for the detection of total viable bacteria. The study employed E. coli M23 bacteria as a model organism, with an analysis time of only 30 min. The method demonstrated a limit of detection (LOD) of 184 CFU mL−1 and 14 cells mL−1 for total viable count and total cell count, respectively. Furthermore, this new approach is capable of detecting the microbial quality standard limits for food contacting surfaces (10 CFU cm−2) and meat (1.99 × 104 CFU cm−2) by swabbing an area of 10 × 10 cm2. In contrast to the culture-based methods usually employed in food processing facilities, this isotachophoretic technique enables easy and rapid detection (<30 min) of microorganisms, facilitating crucial decision-making essential for maintaining product quality and safety. [Display omitted] • This paper reports an ITP method to detect viable bacteria, with the potential to replace traditional plate count method. • The method identifies contaminated surfaces within 30 minutes, mitigating the risk of foodborne illness outbreaks. • The method can be adapted to various settings with modifications to detect total viable count. [ABSTRACT FROM AUTHOR]

• A fluorescence imaging system was developed to detect pork quality. • Fluorescence images can establish PLSR models of TVB-N, TVC, and pH. • Fluorescence image PLSR models accurately predict TVB-N and TVC quality indicators. • Fluorescence image and hyperspectral data PLSR models are largely comparable. • Combining fluorescence and color imaging improves the model's predictive ability. This study aimed to develop a cost-effective fluorescence imaging system to rapidly monitor pork freshness indicators during chilled storage. The system acquired fluorescence images of pork and the color features were extracted from these images to establish partial least squares regression (PLSR) models to predict total volatile basic nitrogen (TVB-N), total viable count (TVC), pH for pork. For TVB-N, TVC and pH values, R p were 0.92, 0.88 and 0.74, residual predictive deviation (RPD) were 2.24, 2.03, and 1.19, respectively. For TVB-N and TVC indicators showed that the predictive ability of this model was largely comparable to that of fluorescence hyperspectral imaging. However, combining fluorescence and color imaging improved the model's predictive ability. For TVB-N, TVC and pH, R p were 0.94, 0.93 and 0.85, RPD were 2.62, 2.59, and 1.95, respectively. Therefore, this study developed a system with great potential for detecting the value of most pork quality indicators in real-time. [ABSTRACT FROM AUTHOR]