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Background: 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., Results: 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 × 10 4  CFU cm -2 ) by swabbing an area of 10 × 10 cm 2 ., Significance: 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., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Michael Breadmore reports financial support was provided by Australian Meat Processor Corporation. Shane Powell reports financial support was provided by Australian Meat Processor Corporation. Michael Breadmore serves as an editor on ACA. Thisara Kumarajithdeclares no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

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 log 10 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.

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., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

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.

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/cm 2 ) 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/cm 2 , 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.

Background and Aim: Milk is a highly perishable commodity, which is subjected to various types of contamination right from the farm level to the consumers' table. This study aimed to assess the quality of raw milk sold in and around Guwahati city based on the microbial load., Materials and Methods: A total of 200 raw pooled milk samples collected from 25 different locations in and around Guwahati city were subjected to quality evaluation based on the methylene blue reduction test (MBRT), standard plate count, and coliform count as per the standard procedure., Results: Out of the 200 samples evaluated, more than 50% of them were graded as poor to very poor quality based on the MBRT results. None of the samples could be graded as excellent quality and only 14.5% were graded as good quality. The standard plate count and coliform count of all the raw milk samples were found to be significantly higher than the legal standard. A highly significant (p<0.01) difference was observed for standard plate count and coliform count among the different locations in and around Guwahati city., Conclusion: From the present study, it could be inferred that raw milk sold in most parts of Guwahati city do not confer to the legal microbiological standard and may pose a high risk of milk-borne illness among consumers of the city, which needs a systematic series of actions to be implemented properly., (Copyright: © Kakati, et al.)

Aim: This study aimed to analyze biological and microbiological parameters of Clarias gariepinus bred at Chundzha natural hot spring in the Almaty region of Kazakhstan, a new feed additive, namely, the prebiotic "Ceobalyk.", Materials and Methods: Two groups (50 heads each) of fish of the same age were established and kept in specialized rectangular pools of AsylTasEngineering LLP. The experiment lasted 61 days. We used the feed additive "Ceobalyk", developed based on natural minerals. Feed additive was added to the feed of the experimental group of fish in an amount of 10% per 1 kg of the main diet. Laboratory studies were conducted at the laboratories of the Kazakhstan-Japan Innovation Center. The quality of the fish was studied in accordance with the standards of the Republic of Kazakhstan and interstate standards., Results: In biological and microbiological studies of all samples of African sharptooth catfish, which received a new type of feed additive "Ceobalyk", the pH values of fish meat in the experimental groups were normal and varied in the range from 6.5 to 6.7. When setting up the reaction with copper sulfate, the reaction was positive. During bacterioscopy, there was a noticeable decrease in the number of microbes (2-3 bacteria less) in comparison with the control. An increase in the indices of the absolute body length and body width was observed by the end of the study. The body length in the experimental group was significantly greater (by 2.12% on average) than that in the control group. In the experimental variant, the average weight of fish was 21.8% higher. As a result of organoleptic studies, it was revealed that the musculature of the fish of the experimental groups was dense and elastic; when pressed on the skin with a finger, a fossa did not remain; the smell was specific, fresh. When tested by cooking, the broth was transparent and aromatic., Conclusion: This feed additive "Ceobalyk" does not cause deviations in the physiological status of fish and can be used as part of the main diet., (Copyright: © Sarsembayeva, et al.)

Matching the general trend of replacing synthetic additives with healthier natural products, the present research studies the effects of different concentrations of chokeberry extract which substitute carmoisine dye in jelly candies. Also, the colour and antioxidant properties of the aforementioned extract and their changes at various pH and in presence of different mineral salts from foods are analysed. The phenolic content of the extract was determined using HPLC and spectrophotometric methods. A high concentration of polyphenols was found in the chokeberry extract, of which around 97% were flavonoids. Catechin, epicatechin, ferulic acid and its methyl esther, protocatechuic, gallic and para -hydroxybenzoic acids were the major phenolics identified in the extract. The total antioxidant activity decreased in acidic media, while close-to-neutral and alkaline pH values did not exhibit any effect on this parameter. Furthermore, the green/red colour parameter, the chroma and the hue angle were enhanced in the most acidic media (pH 2.3 and 3.5). From the studied salts, CaCl 2 and KNO 3 had the most significant effects on colour. The chokeberry extract proved to be suitable as replacement of carmoisine dye in jelly candies, as the physicochemical and microbiological properties comply with the regulated requirements. More than that, the extract improved the antioxidant and sensory properties of jellies in all studied concentrations and the best total sensory score was obtained for 1.5% extract. After 5 and 50 days of storage, the microbiological properties were improved in candies prepared with aronia extracts compared to carmoisine, as the total viable count registered important diminutions., Competing Interests: Conflict of interestThe authors have declared no conflict of interest., (© Association of Food Scientists & Technologists (India) 2020.)

Listeriosis is a food borne disease associated with high hospitalization and fatality rates; in 2014, EU member states reported 2194 cases with 98.9% hospitalization rates and 210 fatalities. Proper risk analysis and the development of effective food safety strategies critically depend on the knowledge of the growth characteristics of L. monocytogenes on the product in question. Ready-to-eat (RTE) salads present a challenge in this context due to the absence of a heat treatment step before consumption. This study provides challenge-test based data of the growth characteristics of L. monocytogenes on twelve RTE salads. The food matrix, storage time and storage temperature were factors with a significant impact on the growth of L. monocytogenes. While most tested salads permitted a significant increase of L. monocytogenes in at least one of the tested conditions, no growth was observed on celeriac, carrot and corn salad products. There was a considerable increase in growth at 8 °C compared to 5 °C. Our data indicate that the reduction of the storage temperature at retail level to 5 °C and product shelf life could help mitigate the risk of L. monocytogenes in RTE salads., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We tested the growth potential of Listeria monocytogenes on six RTE fruit products at low (4°C at the factory followed by 8°C retail/home storage) and abusive (4°C followed by 12°C) storage temperatures. Sliced coconut and fresh cut cantaloupe, as well as a fruit mix containing diced pineapple, cantaloupe, apples and grapes supported the growth of L. monocytogenes with a growth potential δ>0.5 log CFU/g over six days. Mangoes, a mix of diced kiwi, cantaloupe and pineapple as well as a mix of diced pineapple, mango, grapefruit, kiwi and pomegranate did not support a growth potential that exceeded 0.5 log CFU/g over six days. The growth potential of L. monocytogenes correlated significantly with the pH; no product with a pH below 4 showed a significant growth potential of L. monocytogenes . Time after inoculation was also a significant predictor of the growth potential, while the fruit type and storage temperature were not., Competing Interests: Conflict of interest: The authors declare no potential conflict of interest.

Objectives: This study aims to assess the bacteriological quality of marketed raw meat with a special emphasis on isolation of Escherichia coli, Salmonella spp., Shigella spp., Vibrio spp., Pseudomonas aeruginosa and Staphylococcus aureus in raw meat marketed in Dharan. Altogether 50 meat samples were collected from local markets of Dharan and transported to the microbiology laboratory at 4 °C. The meat samples were homogenized in a sterile glass homogenizer and the possible pathogens were isolated and identified by conventional microbiological techniques., Results: The mean total viable count values were found having a mean count of 8.22 ± 0.14, 8.29 ± 0.17, 7.87 ± 0.18 and 7.92 ± 0.19 in terms of log 10 CFU/g ± Standard Error for chicken, pork, buffalo, and goat meat respectively. Coliforms were found in 84% samples, S. aureus was found in 68% samples, Salmonella spp. in 34% samples, Shigella spp. in 6% samples, Vibrio spp. in only 3 samples and P. aeruginosa was isolated from 40% sample. Higher microbial load and presence of intestinal commensals E. coli, Salmonella spp., Shigella spp., Vibrio spp indicates that meat might be contaminated by the visceral content and consumers are at risk of getting a foodborne disease when eaten raw.

Background: The present study determined the heavy metal contamination (mercury, cadmium, lead, arsenic and nickel) of nori, restaurant-served sushi and ready-to-eat sushi meals available via retail chains. Moreover, both microbiological load and biogenic amine content in ready-to-eat sushi meals were analysed., Results: All of the nori samples contained high levels of Cd (2.122 mg kg -1 ), Ni (0.715 mg kg -1 ), As (34.56 mg kg -1 ) and Pb (0.659 mg kg -1 ). The studied sushi samples contained high levels of Ni and Pb, reaching 0.194 and 0.142 mg kg -1 wet weight, respectively, being potentially hazardous to women during pregnancy and lactation and small children. None of the studied samples contained high levels of Hg. Overall, 37% of ready-to-eat sushi meals exceeded a microbiological load of 10 6  cfu g -1 . However, biogenic amine content in all of the samples was low, with a highest histamine content of 2.05 mg kg -1 ., Conclusion: Sushi is not the source of high levels of biogenic amines even with high microbiological loads. Nevertheless, the high microbiological loads at the end of the shelf-life indicate that some processors might have problems with the distribution chain or implement a poor hygienic regime. Moreover as a result of possible risk associated with heavy metal contamination, the present study highlights the need to establish new regulations regarding the contamination of nori and sushi. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

The freshness of meat products during storage has received unprecedented attention. This study was conducted to investigate the feasibility of a hyperspectral imaging (HSI) technique to determine the freshness state of cooked beef during storage and identify the contaminated areas on the surface of spoiled samples. Hyperspectral images of cooked beef were acquired in the wavelength range of 400-1000 nm and the freshness state of all samples was divided into three classes (freshness, medium freshness, and spoilage) using the measured total viable count (TVC) of bacteria. Fifteen feature spectra variables were extracted by random frog (RF); based on this, six optimal wavelength variables were further selected by correlation analysis (CA). Partial least squares (PLS) and least squares-support vector machine (LS-SVM) classification models were established using different spectral variables. The results indicated that the performance of the RF-CA-LS-SVM classification model with a high overall classification accuracy of 97.14%, the results of sensitivity and specificity in the range of 0.92-1, and the κ coefficient of 0.9575 in the prediction set were obviously superior to other models. Spoiled samples were further obtained using a RF-CA-LS-SVM model, and then six feature images were extracted and further fused by principal component analysis (PCA). A PC3 image was used to segment successfully the contaminated areas from normal areas of cooked beef images using the Otsu threshold algorithm. The results demonstrated that HSI has great potential in classifying the freshness of cooked beef and identifying the contaminated areas. This current study provides a foundational basis for the classification and grading of meat production in further online detection.

The aim of this survey was to obtain data on microbiological contamination of pig carcasses and environments in three large-scale Italian slaughterhouses (identified as A-B-C) located in Northern Italy. Each slaughterhouse was visited six times. Five carcasses and three different sites of the slaughterhouse (before and during slaughter) were sampled on each sampling day. A single pooled caecal sample was taken on each sampling day. A total of 90 carcasses, 108 environmental samples and 18 caecal samples were collected. Samples from pig carcasses and slaughterhouse environment were analyzed for total viable count (TVC), Enterobacteriaceae count (EBC) and Salmonella. The caecal contents were examined for Salmonella. Carcasses from slaughterhouse A presented the greatest TVC and EBC mean log value, whereas environmental samples collected during slaughter activities from slaughterhouse C showed the greatest TVC and EBC mean log value. As far as the environmental samples collected before slaughter activities are concerned, an average up to 6 log 10 colony forming unit (CFU)/cm 2 TVC in two slaughter plants (A and C) and 5 log 10 CFU/cm 2 TVC in one slaughter plant (B) was detected. Salmonella was recovered in two slaughterhouses (A and B). Four different Salmonella serotypes were detected in the positive samples (11). Within serotype S. Rissen and S. Typhimurium monophasic-variant isolates, two pulsed-field gel electrophoresis patterns were identified. The findings in this survey suggest that carcass contamination is influenced by the slaughterhouse plant and this could be a result of differences in line speed. The results of environmental sampling have not shown an association with the slaughterhouse plant.

Legionella spp. are ubiquitous in aquatic habitats and water distribution systems, including dental unit waterlines (DUWLs). The aim of the present study was to determine the prevalence of Legionella in DUWLs and tap water samples using PMA-qPCR and standard culture methods. The total viable counts (TVCs) of aerobic heterotrophic bacteria in the samples were also determined. Legionella spp. were detected and quantified using the modified ISO 11731 culture method. Extracted genomic DNA was analysed using the iQ-Check Quanti Legionella spp. kit, and the TVCs were determined according to the ISO protocol 6222. Legionella spp. were detected in 100% of the samples using the PMA-qPCR method, whereas these bacteria were detected in only 7% of the samples using the culture method. The number of colony forming units (CFUs) of the TVCs in the DUWL and tap water samples differed, with the bacterial load being significantly lower in the tap water samples (p-value = 0). The counts obtained were within the Italian standard range established for potable water in only 5% of the DUWL water samples and in 77% of the tap water samples. Our results show that the level of Legionella spp. contamination determined using the culture method does not reflect the true scale of the problem, and consequently we recommend testing for the presence of aerobic heterotrophic bacteria based on the assumption that Legionella spp. are components of biofilms.

Quality assessment of finfish fillets during storage is important to be able to predict the shelf life of the fresh product during distribution. Microbial, chemical (pH, TMA, and TVB-N), and sensory (Quality index assessment QIA, Torry scheme) changes in vacuum-packaged blue-spotted emperor (Lethrinus sp), saddletail (Lutjanus malabaricus), crimson snapper (Lutjanus erythropterus), barramundi (Lates calcarifer), and Atlantic salmon (Salmo salar) fillets stored at 4°C were evaluated for 5 days. Microbiological study included evaluation of TVC (total viable counts), total psychrotrophic organisms, and H2S-producing bacteria. Numbers increased during storage time and reached an average of 8.5, 8.5, and 9.2 log10 cfu/g, respectively, for the five different fish species. These levels were above accepted microbiological limits for fish fillets. Although the sensory analyses showed a decrease in quality, none of the finfish fillets were considered unacceptable at the end of the storage trial. Chemically, there was a slight pH increase, but trimethylamine (TMA) levels remained low. However, total volatile basic nitrogen (TVB-N) levels increased over time, reaching levels above 35 mg/100 g for blue spotted emperor, saddletail snapper, and crimson snapper by the end of the storage period. Results show that the deterioration of finfish fillet quality is a complex event of biochemical, sensory, and microbial factors, and multiple analyses may be required to define acceptability.

Pistacia lentiscus fruits are ingredients of traditional Cypriot sausages. The objective of this study is to evaluate P. lentiscus extracts as natural additives to the sausages. First, the phenolic content and antioxidant activity of fruit and leaf extracts were determined. Results revealed that leaves are richer source of polyphenolic antioxidants than fruits, with methanol being the better extraction solvent. In the next step, the antioxidant and antimicrobial effects of methanolic extracts (300 mg/kg) in the pork sausage formulation were investigated. Peroxide, acid and thiobarbituric acid-reactive substance values demonstrated that both fruit and leaf extracts reduced the rate of lipid oxidation of sausages at 4 °C. Total viable count revealed significant differences on the fifth day of storage, with better microbial inhibition by leaf extract. No significant differences between the extracts were observed after the tenth day of storage. Overall, the extracts can be used to prevent lipid oxidation and reduce microbial spoilage during the first days of storage of fresh traditional pork sausages.

Context: The survival of atraumatic restorative treatment (ART) restorations would probably increase if near total elimination of cariogenic microorganisms could be done in the process of cavity cleaning before going ahead with the restoration. Thus, use of naturally occurring disinfecting agents for achieving this goal could herald a new beginning in the field of contemporary minimum intervention dentistry., Aims: To evaluate the efficacy of hand instruments in excavating dental caries and comparatively evaluate the roles of Aloe vera and propolis as potential cavity disinfecting agents after minimally invasive hand excavation of dental caries., Settings and Designs: Experimental, in vivo intergroup split mouth, randomized clinical trial., Subjects and Methods: The study included Group I (Control), Group II (A. vera) and Group III (propolis). Ten patients with three teeth each have occlusal/occlusoproximal lesions suitable for ART were selected. Dentinal samples were collected three times from each tooth viz., preexcavation, postexcavation and postdisinfection of the cavities. These dentinal samples were subjected to microbiological analyses for total viable count., Statistical Analysis Used: Repeated measures of analysis of variance (ANOVA) with Bonferroni post-hoc test and one-way ANOVA with Tukey post-hoc test., Results: In all the three groups, significant amount of bacteria were left behind after hand excavation. Group II and Group III, in which cavities were treated with A. vera and propolis extracts respectively, showed a significant reduction in the bacterial counts when compared to control the group., Conclusions: Hand excavation alone does not completely eliminate bacteria, which may predispose treated teeth to secondary caries. Both propolis and A. vera extracts can be used as potential natural disinfecting agents, thereby embracing the concept of phytotherapy in minimum intervention dentistry.

Objective: The aim of this study was to assess the anti-microbial efficacy of an indigenously prepared caries removing gel, in primary molars., Materials and Methods: Twenty teeth with broad occlusal cavitated lesions that fulfilled the clinical and radiographic criteria formed the study group. These teeth were subjected to chemomechanical method of caries removal, using an indigenously prepared caries removing gel. Prior to and following caries removal, the dentin samples were analyzed for total viable count and lactobacilli count., Results: The percentage of reduction in the total viable count was 92.4% and in the lactobacilli count it was 94.1%, which was statistically highly significant., Conclusion: Removal of carious tissue with a caries removing gel, a natural plant extract, proved to be efficient, easy to perform, and comfortable for the patient.