Responding to the ever-growing concern about safe foods and security, the food industries are forced to seek an emerging technology capable of detecting and quantifying contaminations, especially those of biological origin. Among the different emerging technologies, hyperspectral imaging is considered a good alternative as it can be easily applied at all steps of the food production process and is a non-destructive technique. This paper reviews targeted analytical applications of hyperspectral imaging in monitoring biological contaminants in food. First, traditional techniques for detection of biological contaminants in foods are presented, where disadvantages for practical applications are highlighted and explained in detail. Second, prominent applications of hyperspectral imaging from the last decade to food safety and quality assessment are reviewed, specifically focusing on both deteriorative and pathogenic microorganisms, microbial toxins, and parasites; whether acting individually or collectively in spoiling food products and/or represent a health risk to the consumers. Finally, relevant current and future challenges, advantages and disadvantages of hyperspectral imaging applications are briefly examined.

The objective of the study was to evaluate the influence of the type of solvent (commercial alcohol 96% and absolute ethanol) and pH (1.7, 3.5 and 5.5) in the process of extracting phenolic compounds present in the residues of the wine production to apply them as an agent Silver nitrate precursor reducer (AgNO3) in the green synthesis of silver nanoparticles (NP Ag). The silver colloids obtained were initially evaluated by UV-Vis spectrophotometry, which determined in the foreground the presence of colloids with high production of nanoparticles in the cases of commercial alcohol 96% and ethanol both with pH = 3.5, with absorbance values in 2.21 u.a/425.9 nm. and 2.8 u.a /431.8 nm. respectively; It was also possible to visualize a medium production with both types of solvents, but with pH = 5.5, the results being 1.91 u.a./424.6 nm. for commercial alcohol 96% and 1.98 u.a./425.2 nm. for ethanol, in all the cases described above the spectra show high monodispersity due to the characteristics of the absorbance peak; It was also possible to show a minimum production of NP Ag when 96% commercial alcohol was used at a pH = 1.7 (0.392 u.a./415.4 nm.) but with high polydispersity; in the case of ethanol pH = 1.7 there was no presence of optical absorbance peak, which implies the non-formation of NP Ag; It should be noted that stability over time was also evaluated; as well as FTIR spectra, which determine the presence of phenolic radicals in the cases described above. The results suggest the potential reducing effect of the alcoholic extract of residues from wine production at a pH value = 5.5, because it achieved a complete reaction and are stable over time.

In the agribusiness sector, the raw material is subjected to transformation processes to give it added value, for this purpose various methodologies are implemented which facilitate its consumption, but wine residues on the contrary generate one of the main environmental problems. This research adopts the study of the influence of the resting time of the extract in alcoholic solvent (96%) of residues from wine production, evaluating the concentration of phenolic compounds for about 114 days (a total of six data) and their once silver nanoparticles (NP Ag) were synthesized by the green chemistry method (biosynthesis), also evaluating the reducing potential of the extract with respect to the AgNO3 precursor for the formation of NP Ag. The evaluation of the extract was by quantifying the polyphenol content by the Follin-Ciocalteu method. FTIR (Fourier transform infrared spectroscopy) analysis was performed only to the initial sample for comparative evaluation between alcoholic extract of wine residues and NP Ag; NP Ag were characterized by UV-Vis spectrophotometry (Ultraviolet-visible). The results suggest that despite the fact that the content of phenolic compounds is reduced over time, there are hypotheses that consider a constant behavior and even an increase in reducing capacity. This is how the results by spectrophotometry of NP Ag show a increase in absorbance peak that implies a greater production of nanostructures, with antioxidants being the ones involved in the chemical reduction process.

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