The consumption of fish in food may contain mercury, a harmful element and dangerous chemical detrimental to human health. The purpose of this study was to determine the mercury level in the hair of pregnant women with different fish intakes in their diets. The concentration of total mercury in hair was determined using an atomic absorption spectrometer. In this study, 98 pregnant women were invited to participate (aged from 18 to 48 years). The mean content of mercury in the hair of pregnant women in Northwestern Russia was 0.428 mg/kg (ranging from 0.018 to 3.1 mg/kg). As a result, 22% of women had mercury values above 0.58 mg/kg, which is considered dangerous for the fetus. The hair mercury concentration in a village area was higher than that in a city area (i.e., 0.548 mg/kg and 0.326 mg/kg). Moreover, the maximum level of mercury was noted for a group of pregnant women who consumed more than 5 kg/month of fish and fish products. Furthermore, the consumption of freshwater fish in the diet leads to a higher mercury content in the hair of pregnant women than the consumption of marine fish.

Background: In the agro-industrial sectors, including fisheries, there is a growing focus on rapidly determining the composition and quality of food products. Traditional chemical methods are too slow for quick quality assessments. Spectral methods have become preferred for rapid analysis, although the spectral range suitable for determining the storage days of fish samples has not been thoroughly explored.Purpose: To evaluate the shelf-life and freshness of refrigerated rainbow trout using mid-infrared spectroscopy.Materials and Methods: Refrigerated rainbow trout steaks stored at +4 °C were examined. The fish were raised in an open tank at Lake Motkozero in the Vologda region. A mid-infrared FT-801 FTIR spectrometer with an attenuated total internal reflection (ATR) attachment was employed to determine the fish's shelf-life, freshness, and quality. The spectrum range spanned from 4000 to 700 cm-1 with a resolution of 4 cm-1, conducting 16 scans. Spectral data were analyzed using ZaIR 3.5 software, with measurements taken daily over a 16-day storage period.Results: Mid-infrared spectroscopy effectively differentiated rainbow trout samples by storage day, with each day displaying a unique spectral signature. The spectral range of 1700–1500 cm-1 clearly distinguished between samples from the first and last days of storage (day 16), showing an increase in absorption intensity at wavelengths corresponding to amides and amino groups, indicative of biochemical changes due to spoilage.Conclusion: This study's findings contribute to developing a new, rapid, and non-destructive method for assessing fish freshness, which is crucial for food safety control authorities and consumers. The methods developed hold significant potential for optimizing quality control processes in the food industry.

Sterlet is a perishable product; therefore, its freshness monitoring and shelf-life evaluation are important. In this study, a series of analytical techniques named physicochemical, microbiological, sensory, colorimetric, and mid-infrared and fluorescence spectroscopies were applied on Sterlet (Acipenser ruthenus) samples during 18 days of storage at 4 °C. The water content increased from 72.8 g/100 g on day 1 to 77.81 g/100 on day 14. Regarding the peroxide value (PV), the initial value was 4.17 meq/kg of Sterlet on day 1, reaching a maximum on day 4 (4.9 meq/kg of Sterlet), and then it decreased gradually, attaining a value of 0.7 meq/kg of Sterlet on day 18. Generally, the thiobarbituric acid reactive substance (TBARS), total viable count (TVC) and psychrotrophic count (PTC) increased during the storage time and increased from 0.03 to 0.13 MDA eq./kg of Sterlet sample, 2.27 to 9.09 log10 CFU/g, and 2.18 to 9.15 log10 CFU/g, respectively, on day 1 and 18, respectively. The microbiological and sensory analyses indicated that Sterlet samples were acceptable for human consumption up to 7 days of storage at 4 °C. This result was confirmed by fluorescence measurements, since the principal component analysis (PCA) applied to the NADH and MIR spectra allowed for a clear differentiation between Sterlet samples aged 7 days or less from the others. This trend was confirmed by the factorial discriminant analysis (FDA) applied to the NADH and MIR spectra, since a correct classification with leave-one cross-validation of 94.44% was observed. In addition, the heatmap of the Pearson correlation coefficients showed high correlations between overall acceptability and microbiology parameters and the structural properties of Sterlet samples during storage, indicating that the modifications observed at the macroscopic level were related to those notedat the molecular scale.

According to the FAO, the world is gradually transitioning from industrial fishing to aquaculture, which accounted for 130.9 million tons of fish in 2022. Data on the state of aquaculture and the prospects for its development in the world, in the Russian Federation, in particular the Vologda oblast, are presented. The Russian Federation has a huge fish farming potential. In 2023, salmon fish occupy the first place in the territory of the Russian Federation in terms of commercial aquaculture production. One of the common species for commercial fish farming is rainbow trout (Oncorhynchus mykiss). The widespread development of industrial trout farming in Russia is possible due to the suitable geographical location and favorable climatic conditions for breeding rainbow trout. Since the first half of the 20th century, the breeding of commercial fish species has been the most important direction for the development of fisheries in the reservoirs of the Northwestern Federal District of Russia, and therefore at least 25 species of fish, including rainbow trout, have been introduced into the reservoirs of the Vologda Region. Currently, there are 15 operating enterprises in the Vologda Region and 13 more commercial fish farming enterprises are planned to operate. The ecology of rainbow trout is considered, and a comparative characteristic of the favorable habitat conditions of this species with the conditions of the reservoirs of the Vologda region is given. It is noted that the reservoirs of the Vologda region are suitable for breeding rainbow trout in aquaculture conditions according to various criteria.

The interaction of estrogen receptor alpha (ERα) with various metabolites—both endogenous and exogenous, such as those present in food products, as well as gut microbiota-derived metabolites—plays a critical role in modulating the hormonal balance in the human body. In this study, we evaluated a suite of 27 machine learning models and, following systematic optimization and rigorous performance comparison, identified linear discriminant analysis (LDA) as the most effective predictive approach. A meticulously curated dataset comprising 75 molecular descriptors derived from compounds with known ERα activity was assembled, enabling the model to achieve an accuracy of 89.4% and an F1 score of 0.93, thereby demonstrating high predictive efficacy. Feature importance analysis revealed that both topological and physicochemical descriptors—most notably FractionCSP3 and AromaticProportion—play pivotal roles in the potential binding to ERα. Subsequently, the model was applied to chemicals commonly encountered in food products, such as indole and various phenolic compounds, indicating that approximately 70% of these substances exhibit activity toward ERα. Moreover, our findings suggest that food processing conditions, including fermentation, thermal treatment, and storage parameters, can significantly influence the formation of these active metabolites. These results underscore the promising potential of integrating predictive modeling into food technology and highlight the need for further experimental validation and model refinement to support innovative strategies for developing healthier and more sustainable food products.

Потенциал рамановской спектроскопии как метода экспресс-оценки срока хранения и свежести филе охлажденной радужной форели