Mycotoxins are toxic compounds produced mainly by fungi of the genera Aspergillus, Fusarium and Penicillium. In the food chain, the original mycotoxin may be transformed in other toxic compounds, reaching the consumer. A good example is the occurrence of aflatoxin M1 (AFM1) in dairy products, which is due to the presence of aflatoxin B1 (AFB1) in the animal feed. Thus, milk-based foods, such as cheese and yogurts, may be contaminated with this toxin, which, although less toxic than AFB1, also exhibits hepatotoxic and carcinogenic effects and is relatively stable during pasteurization, storage and processing. For this reason, the establishment of allowed maximum limits in dairy products and the development of methodologies for its detection and quantification are of extreme importance. There are several methods for the detection of AFM1 in dairy products. Usually, the analytical procedures go through the following stages: sampling, extraction, clean-up, determination and quantification. For the extraction stage, the use of organic solvents (as acetonitrile and methanol) is still the most common, but recent advances include the use of the Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) and proteolytic enzymes, which have been demonstrated to be good alternatives. For the clean-up stage, the high selectivity of immunoaffinity columns is still a good option, but alternative and cheaper techniques are becoming more competitive. Regarding quantification of the toxin, screening strategies include the use of the enzyme-linked immunosorbent assay (ELISA) to select presumptive positive samples from a wider range of samples, and more reliable methods—high performance liquid chromatography with fluorescence detection or mass spectroscopy—for the separation, identification and quantification of the toxin.

Mycotoxins are a group of secondary metabolites produced by different species of filamentous fungi and pose serious threats to food safety due to their serious human and animal health impacts such as carcinogenic, teratogenic and hepatotoxic effects. Conventional methods for the detection of mycotoxins include gas chromatography and high-performance liquid chromatography coupled with mass spectrometry or other detectors (fluorescence or UV detection), thin layer chromatography and enzyme-linked immunosorbent assay. These techniques are generally straightforward and yield reliable results; however, they are time-consuming, require extensive preparation steps, use large-scale instruments, and consume large amounts of hazardous chemical reagents. Rapid detection of mycotoxins is becoming an increasingly important challenge for the food industry in order to effectively enforce regulations and ensure the safety of food and feed. In this sense, several studies have been done with the aim of developing strategies to detect mycotoxins using sensing devices that have high sensitivity and specificity, fast analysis, low cost and portability. The latter include the use of microarray chips, multiplex lateral flow, Surface Plasmon Resonance, Surface Enhanced Raman Scattering and biosensors using nanoparticles. In this perspective, thin film sensors have recently emerged as a good candidate technique to meet such requirements. This review summarizes the application and challenges of thin film sensor devices for detection of mycotoxins in food matrices.

One of the most intriguing dogmas in neurosciences—the empirical lack of brain neuronal regeneration in adulthood onwards to late life—began to be debunked initially by research groups focused on understanding postnatal (early days/weeks of murine and guinea pigs) neurodevelopmental and neuroplastic events [...]

The occurrence of Aflatoxin M1 (AFM1) in milk results from ingestion of contaminated feed with Aflatoxin B1 by dairy animals, its conversion into AFM1, and secretion in milk. The objective of this work was to investigate AFM1 fate along goat and sheep cheese production. Cheese production was carried out using spiked milk (levels between 0.08 and 0.10 μg/L). Samples were collected throughout the production and analyzed by immunoaffinity cleanup and chromatography. Higher concentration of AFM1 was always observed in curd rather than in whey; with a mean enrichment factor of 1.8. A strong and positive correlation was established between casein content and AFM1 percentage in curd. Throughout production, a significant increase in AFM1 concentration on a wet basis was observed. In turn, on a dry basis, there was no statistically significant reduction during ripening. These observations are justified by the loss of cheese moisture and the absence of AFM1 degradation. Practical applications The distribution of aflatoxin M1 during the production of two different cheeses was studied, where the amount of the toxin was monitored on a wet and a dry basis. On the wet basis, there was a continuous increase in concentration; which has already been reported by different authors, without clarifying whether this increase is due exclusively to the loss of moisture during milk processing. The same study on a dry basis allowed us to conclude that under the tested conditions, there is no degradation of the toxin, and the concentration increase observed previously was in fact due to the loss of humidity.