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From farm to plate, food meets various challenges and pollution. Food detection is essential to ensure food safety. Although detection techniques have obtained great development, the accuracy, sensitivity and operating conditions still have room for improvement. Composed of dielectric media with different refractive indices to form a periodic structure, an optical material named photonic crystal (PC) can offer a breakthrough. Owing to the periodic structure, Bragg diffraction happens with optical waves propagating in a PC and photonic band gap (PBG), a characteristic parameter of the PC, will form. The properties of PBG are widely used in the field of detection. Combined with the techniques of biology, immunology, optics and fluorescence etc., PCs can play the role of specific, efficient, sensitive and convenient sensors in food detection. At present, PCs have been successfully applied to analyze hazardous substances in food, such as microorganisms, biotoxins, veterinary drug residues, pesticide residues, excessive additives, illegal additives, environmental pollutants and heavy metal composition. This article introduces PCs about the fabrication methods, principles and techniques applied in detection and research progress in food detection. [ABSTRACT FROM AUTHOR]

In recent years, developing rapid, simple, and effective new methods to monitor food safety is standing out enough to be noticed. Electrospinning is an easy, versatile, and low-cost technique to fabricate multifunctional micro-and nanomaterials. The combination of electrospinning and biosensors is one of the most promising strategies and is expected to replace traditional detection materials. This paper reviews the research progress of electrospinning in food detection, including electrospinning materials generally used in the food field with their benefits of high aspect ratio, large specific surface area, tunable porosity, easy functionalization, easy handling, mechanical stability, such as natural polymers, synthetic polymers or the mixture of both. Besides, we also emphatically introduced the application of their intrinsic characteristics combined with biosensing platforms and list the sensitivity and detection limit of various methods and materials in detection, as well as their application potential, and the challenges faced by the on-site detection and the large-scale commercial applications in the food industry as future exploration headings, giving new thinking of nanomaterial applications for food safety detection. [ABSTRACT FROM AUTHOR]

A novel, integrated, real‐time electrochemical loop‐mediated isothermal amplification (LAMP) device for pathogen detection in food was developed. The electrochemical LAMP device for detection of the vt gene in E. coli O157 : H7 and invA gene in Salmonella enterica was implemented with DNA intercalating probes‐methylene blue. To improve assay efficiency, the optimal concentration of MB was determined to be 30 μM. The real‐time electrochemical LAMP results of gene serial dilutions were compared to the fluorescence‐based detection method. For E. coli O157 and Salmonella, the assay detection limits were 10 DNA copies and 1 DNA copy, respectively, in a reaction time of less than 30 min. The electrochemical and optical LAMP method analyses were realized with 10 % milk to simulate the turbid environment of real food samples. In real‐time LAMP of Salmonella in a turbid environment, the detection limit of 10 copies without pretreatment was possible using the electrochemical method only. Our electrochemical device was used for bacterial detection in 150 turbid food samples, including juice, milk, and soy milk. This electrochemical device has many advantages, including size, portability, high specificity, and high sensitivity, while also being a user‐friendly device that provides stable signals. Thus, to the best of our knowledge, this new electrochemical device demonstrates the best performance for bacterial detection in the rapid contaminated food detection category. [ABSTRACT FROM AUTHOR]

[Display omitted] • A unique SERS substrate processed by one-step femtosecond laser ablation in Argon. • S-Ag-Ar can detect 10-8mol/L R6G with enhancement factor up to 5.3 × 106. • S-Ag-Ar has high uniformity with relative standard deviation less than 11.97%. • S-Ag-Ar can be stored for more than seven months and shows good universality. • This unique SERS substrate demonstrates good potentials for food safety evaluation. Surface Enhanced Raman Scattering (SERS) is a reliable tool for detection of food additives due to its advantages including rapid detection, non-destructive and excellent sensitivity. Currently, the commercial SERS substrates are not yet satisfactory referring to cost, sensitivity, uniformity and stability. Herein, we report a unique SERS substrate processed by one-step femtosecond laser ablation in Argon. The substrate shows high sensitivity with limit of detection up to 10-8mol/L for Rhodamine 6G (R6G) and enhancement factor up to 5.3 × 106 due to laser induced more plentiful nanostructures and less oxidation in Argon, in addition to high uniformity with relative standard deviation less than 11.97% and long storage time more than seven months. This SERS substrate is capable of detecting the common food additives including malachite green (1 ppm), crystal violet (10-7mol/L), Sudan I (1 ppm), melamin (1 ppm), brilliant blue (1 ppm) and tartrazine (1 ppm). This unique Ag SERS substrate demonstrates good potentials for food safety evaluation. [ABSTRACT FROM AUTHOR]