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Foods are processed to make them available at all places; consequently, our awareness regarding hygiene measures in food production has also increased dramatically over the last decades. In many countries cases associated with foodborne infectious are increased. However, available techniques are unable to effectively control the problem. Further, exploring novel methods and technologies for ensuring the safety of food with effective quality control approaches are under research. Phages are the natural enemies of bacteria, and are more specific to host renders them ideal candidates for applications designed to increase food safety during the production process. Scientific findings are available showing the possibility to use as biocontrol agents against various pathogens without interfering with the natural microflora or the cultures in fermented products. Furthermore, phages or phage derived proteins can also be used to detect the presence of unwanted pathogens in food or the production environments, which allows quick and specific identification of viable cells. Bacteriophages are natural, found in various environments including water; foods etc. and are not found significantly influence the human cells. [ABSTRACT FROM AUTHOR]

The presence of pesticides in milk is a serious concern at the global level, which can threaten human health. Detection of pesticides in milk is a challenge due to their small concentration and large amounts of other interfering substances that can be co-extracted along with the pesticides. In this study, we have compared two variants (original and acetate) of quick, cheap, effective and safe (QuEChERS) method to evaluate the efficiency and suitability of these methods for the extraction of organochlorine and organophosphorous residues from milk using GC-MS/MS. The acetate method was found to be more efficient in terms of recovery of all the studied pesticides, except monocrotophos. It resulted in good linearity (R² > 0.9928% in matrix and >0.9940% in solvent), recovery (71.69%-99.38%) over the range 10-250 ng/ml and precision of RSD% < 20%. This method can be easily applied for the extraction of pesticide residues in milk and its products, and further quantification using GC-MS/MS in the dairy sector. [ABSTRACT FROM AUTHOR]

According to the results of this study, the paper strip biosensor can detect pesticide at very low concentration like fungicide, organochlorine, organophosphate, carbamate, and herbicide group ranges from 1 to 10, 1-50, 250-500, 1-50, and 1 μg/L, respectively in animal feed, water, milk and soil. This is a significant improvement from the previous study, which found that the paper strip biosensor could only detect pesticide levels of up to 500 or 1000 μg/L. A total of 436 samples were collected from the dairy farm, including 58 samples of green feed, 54 samples of dry feed, 45 samples of concentrated feed, 41 samples of fermented feed, 49 samples of manure, 54 samples of soil, and 86 samples of milk. PSA (Primary Secondary Amine) and MgSO 4 (1:2 ratio) were used to remove pigments from dairy farm samples to prevent the enzyme-pesticide interaction leading to colour development on the strip, which was successfully achieved. Using a strip-based test and an optimized extraction protocol, pesticides were detected in 38.49% in the samples. Limit of Detection of 15 pesticides from the organochlorine, organophosphate, carbamate, neonicotinoid, pyrethroid, ryanoid, strobilurins, and triazole groups recommended for use in dairy farms were evaluated in feed/fodder. Pesticides were being detected in various dairy farm matrices using the newly developed test. The developed technology can be used as a semi-quantitative test for pesticides monitoring in the dairy farm as well as for screening of primary produce under field condition for organic certification of various food/feed commodities., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier B.V.)

In the food quality and safety arena, there is a need to develop novel and sustainable methodologies that can help in the prevention of foodborne diseases. Herein, we report the development of a rapid conducting polymer strip-based sensor using Polyaniline-pectin (PANI-PEC) for the detection of Escherichia coli in milk and milk products. Polyaniline-pectin nanoparticles stabilized with biopolymer pectin were synthesized and its characterization studies such as FTIR, UV-Vis spectroscopy, electrical conductivity and particle size analysis were done. The assay parameters were optimized for the selective detection of E. coli in milk and milk products. The concentration of PANI-PEC solution immobilized/strip was optimized to be 3 mg/mL as it exhibited good sensitivity and colour intensity. Based on acid production and selectivity for E.coli, concentrations of media components like lactose, tryptophan, yeast extract, chondroitin sulphate, sodium lauryl sulphate, potassium chloride, tergitol-7, gentamycin sulphate and ampicillin trihydrate were optimized as 0.9, 0.1, 0.45, 0.015, 0.1, 2, 0.0125, 0.00016 and 0.015 respectively and sample volume was optimized to 500 μL. The developed PANI-PEC colorimetric strip-based sensor detects 0 . 52  ±  0 . 17 log CFU/mL E. coli within 10: 21 h (h). Further shelf-life study revealed that the developed PANI-PEC colorimetric sensor strips are stable at room temperature up to six months exhibiting the same sensitivity. The results obtained here indicate that this novel and simple paper based colorimetric sensor holds potential for application in food industries as a reliable and rapid method for detection of E. coli in milk and milk products at various stages of production and processing., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Immobilization of Bacillus megaterium spores on Eppendorf tubes through physical adsorption has been used in the detection of aflatoxin M1 (AFM1) in milk within real time of 45 ± 5 min using visual observation of changes in a chromogenic substrate. The appearance of a sky-blue colour indicates the absence of AFM1 in milk, whereas no colour change indicates the presence of AFM1 in milk at a 0.5 ppb Codex maximum residue limit. The working performance of the immobilized spores was shown to persist for up to 6 months. Further, spores immobilized on 96-well black microtitre plates by physical adsorption and by entrapment on sensor disk showed a reduction in detection sensitivity to 0.25 ppb within a time period of 20 ± 5 min by measuring fluorescence using a microbiological plate reader through the addition of milk and fluorogenic substrate. A high fluorescence ratio indicated more substrate hydrolysis due to spore-germination-mediated release of marker enzymes of spores in the absence of AFM1 in milk; however, low fluorescence ratios indicated the presence of AFM1 at 0.25 ppb. Immobilized spores on 96-well microtitre plates and sensor disks have shown better reproducibility after storage at 4 °C for 6 months. Chromogenic assay showed 1.38% false-negative and 2.77% false-positive results while fluorogenic assay showed 4.16% false-positive and 2.77% false-negative results when analysed for AFM1 using 72 milk samples containing raw, pasteurized, and dried milk. Immobilization of spores makes these chromogenic and fluorogenic assays portable, selective, cost-effective for real-time detection of AFM1 in milk at the dairy farm, reception dock, and manufacturing units of the dairy industry.