Madeira wine (MW) oxidative aging results in the formation of several key aromas. Little is still known about their odor relevance to the aroma of the most commercialized MWs. This report presents an in-depth study of the odor impact of sotolon in MW blends. First, its odor perception was estimated in MWs according to ASTM E679, testing different 3-year-old (3-yo) commercial blends. The odor relevance of sotolon in the aroma of 3-, 5-, and 10-yo commercial blends (89 MWs) was then appraised by calculating its Odor Activity Value (OAV), after determining its content by RP-HPLC-MS/MS. The sotolon odor perception in MW was as low as 23 µg/L, although it was found that little differences in the wine matrix influenced its perception. OAVs varied between 0.1 and 22, increasing with the blend age. Considering that 16% of the OAVs are higher than 10 (mostly ≥ 10-yo), sotolon was found to be a key contributor to the overall aroma MW blends.

Madeira wine (MW) encompasses an unusual oxidative ageing process that makes it distinctive. Several metabolites have been related to its quality and safety, such as 5-hydroxymethylfurfural (HMF), furfural, sotolon, and ethyl carbamate (EC). These compounds were quantified over a three-year period to assess their formation rate according to the ageing procedure used: canteiro vs. estufagem. Estufagem, which includes thermal processing of young MWs, promoted greater HMF, furfural, and sotolon accumulation, especially in sweet wines, in which sotolon contributed significantly to aroma (odour active values up to 17.5). Tinta Negra revealed a higher predisposition to form EC while Malvasia and Sercial were less prone to its formation. The formation of furfural, HMF, and EC strongly correlated with the ageing time. Sotolon had a strong correlation with the ageing time in canteiro (r = 0.79) and a moderate correlation in estufagem (r = 0.65). In both ageing procedures, sotolon, furfural, and HMF formation trends strongly correlated with each other (r = 0.74–0.90). In turn, EC also correlated with all furans (r = 0.51–0.85). Yellow tones (b*) correlated with these metabolites only when wines undergo estufagem. This study provides valuable insights to improve MW quality and safety management procedures.

Bisphenol A (BPA) is an endocrine disruptor found in food-contact materials and, even at very low concentrations, poses a serious risk to human health. Therefore, its presence in food should be monitored. Optical fiber sensors are a highly advantageous option for detecting chemical contaminants; however, due to the low concentrations at which these compounds are found, the surface needs to be modified to promote interaction with the target compound. In this work, we present an optical fiber sensor incorporating a microstructured fiber that is sensitive to external media and, therefore, to refractive index variations. To increase sensitivity, the sensor was coated with a chitosan film, a polysaccharide with high biosorbent ability that has been proposed as an effective adsorbent for several contaminants, including BPA. The sensor was then characterized by its response to variations in BPA concentration from 0 to 0.1 mg/mL. The chitosan-coated sensor exhibited a sensitivity over three times higher than that of the uncoated sensor, with a resolution of 9.98 × 10⁻⁴ mg/mL. Washing assays revealed that, although the coating cannot be fully regenerated, the sensor can be reused without requiring a complex or time-consuming procedure.

Bisphenol A (BPA) is a widely used synthetic compound and a well-known endocrine-disrupting chemical that has been linked to a range of health issues and poses significant public health concern. Despite efforts to regulate its use in food-contact materials, BPA remains a significant food contaminant due to its widespread use and its ability to leach into consumer products. Therefore, it is paramount to continue monitoring this contaminant in the food supply chain. This work aims to assess human exposure by investigating the presence of BPA in beverages, including iced teas, fruit juices, water, and carbonated drinks. The analysis by liquid chromatography coupled with fluorescence detection reveals BPA above the limit of quantification in about 30% of samples, with concentrations ranging from 0.15 to 0.94 ng/mL. The highest detection frequencies are observed in iced teas and canned beverages, while water and glass-bottled drinks have the lowest BPA detection frequencies. In the future, we aim to use the results from this study as a reference to optimize a chitosan-coated optical fiber sensor as a possible alternative for rapid BPA detection. A preliminary test showed that the sensor can discriminate between BPA concentrations of 10–100 µg/mL in a real food matrix.