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Biogenic amines (BAs) occur in a wide variety of foodstuffs, mainly from the decomposition of proteins by the action of microorganisms. They are involved in several cellular functions but may become toxic when ingested in high amounts through the diet. In the case of oenological products, BAs are already present in low concentrations in must, and their levels rise dramatically during the fermentation processes. This paper proposes a rapid method for the determination of BAs in wines and related samples based on precolumn derivatization with dansyl chloride and further detection by flow injection analysis with tandem mass spectrometry. Some remarkable analytes such as putrescine, ethanolamine, histamine, and tyramine have been quantified in the samples. Concentrations obtained have shown interesting patterns, pointing out the role of BAs as quality descriptors. Furthermore, it has been found that the BA content also depends on the vinification practices, with malolactic fermentation being a significant step in the formation of BAs. From the point of view of health, concentrations found in the samples are, in general, below 10 mg L−1, so the consumption of these products does not represent any special concern. In conclusion, the proposed method results in a suitable approach for a fast screening of this family of bioactive compounds in wines to evaluate quality and health issues.

Winery wastes are rich in polyphenols with high added value to be used in cosmetics, pharmaceuticals, and food products. This work aims at recovering and purifying the polyphenolic fraction occurring in the malolactic fermentation lees generated during the production of Albariño wines. Phenolic acids, flavonoids, and related compounds were recovered from this oenological waste by green liquid extraction using water as the solvent. The resulting extract solution was microfiltered to remove microparticles and further treated by ultrafiltration (UF) using membranes of 30 kDa and 5 kDa molecular weight cut-offs (MWCOs). The feed sample and the filtrate and retentate solutions from each membrane system were analyzed by reversed-phase liquid chromatography (HPLC) with UV and mass spectrometric (MS) detection. The most abundant polyphenols in the extracts were identified and quantified, namely: caftaric acid with a concentration of 200 µg g-1 and trans-coutaric acid, cis-coutaric acid, gallic acid, and astilbin with concentrations between 15 and 40 µg g-1. Other minor phenolic acids and flavanols were also found. The UF process using the 30 kDa membrane did not modify the extract composition, but filtration through the 5 kDa poly-acrylonitrile membrane elicited a decrease in polyphenolic content. Hence, the 30 kDa membrane was recommended to further pre-process the extracts. The combined extraction and purification process presented here is environmentally friendly and demonstrates that malolactic fermentation lees of Albariño wines are a valuable source of phenolic compounds, especially phenolic acids.

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2020, Tutor:Javier Vicente Saurina Purroy, Biogenic amines are often present in different types of food, but they are especially abundant in wines, cheeses, meat and fish as well as in spoiled products. Besides, the presence of a high content of biogenic amines in food can be an indicator that it has been processed under poor hygiene conditions. These amines are generated mainly from the decarboxylation of the respective amino acids. In moderate concentrations, these compounds can be beneficial for the body as they participate in different cellular functions but when the intake of these compounds is too high for the body, toxicological problems such as migraines, headache, hypo- or hypertension, effects on the vascular or nervous system and anaphylactic shocks can result. Therefore, given the harmful effects that biogenic amines can cause in an organism, it is necessary to establish an effective and selective methods to determine these amines in food in order to avoid the commercialization of any food with high concentration of these compounds. Consequently, research is also needed to establish legal limits on the contents of different biogenic amines in food products. This last point is more complicated because the content of biogenic amines that an organism can tolerate depends on it, in turn, on the catabolic pathways of each individual. Thus, a given concentration of amines can be tolerated by an organism with a normal catabolism, but it can cause harmful effects on a sensitive organism. In wines, the most important biogenic amines are histamine, tyramine, putrescine and cadaverine because they are the most abundant and can cause the greatest number of toxicological problems. Among the different types of wines, red wines have the highest content of biogenic amines. Also, in wines, the presence of ethanol increases the toxicological problems that can cause these biogenic amines because this alcohol inhibits or decreases the activity of amino oxidases responsible for their metabolism. In this project, the following biogenic amines have been considered: ethylamine, methylamine, dimethylamine, ethanolamine, butylamine, isobutylamine, isopentylamine and hexylamine. Although these amines are present at trace level, their study is important as possible descriptors of the health quality of food. To separate and determine them adequately the following studies have been carried out: ▪ A pre-column derivatization reaction has been performed with the 1,2-naphthoquinone-4-sulfonate reagent (NQS) to attach a chromophore group to the initial amines so that they could be detected with an ultraviolet-visible absorption detector. ▪ A liquid-liquid extraction process with chloroform as the solvent and subsequent evaporation until dryness has been used to obtain simpler chromatograms removing efficiently amino acid derivatives and other polar compounds that often interference with the chromatographic separation of biogenic amines, in addition to preconcentrating the extracts obtained. Combination of both derivatization and extraction procedures before the HPLC separation results in an effective clean-up of samples and affords a sensitive determination of biogenic amines. ▪ HPLC has been used as a technique for separating different amines under reversed-phase mode, optimizing the efficiency and resolution by modifying some variables such as the chromatographic column, the elution gradient or the separation temperature. It should be pointed out that due to the consequences of the global pandemic caused by the SARS-CoV-2 virus, significant parts of method optimization and validation studies as well as the analysis of wine and cava samples have not been finished

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2020, Tutor:Javier Vicente Saurina Purroy Biogenic amines are often present in different types of food, but they are especially abundant in wines, cheeses, meat and fish as well as in spoiled products. Besides, the presence of a high content of biogenic amines in food can be an indicator that it has been processed under poor hygiene conditions. These amines are generated mainly from the decarboxylation of the respective amino acids. In moderate concentrations, these compounds can be beneficial for the body as they participate in different cellular functions but when the intake of these compounds is too high for the body, toxicological problems such as migraines, headache, hypo- or hypertension, effects on the vascular or nervous system and anaphylactic shocks can result. Therefore, given the harmful effects that biogenic amines can cause in an organism, it is necessary to establish an effective and selective methods to determine these amines in food in order to avoid the commercialization of any food with high concentration of these compounds. Consequently, research is also needed to establish legal limits on the contents of different biogenic amines in food products. This last point is more complicated because the content of biogenic amines that an organism can tolerate depends on it, in turn, on the catabolic pathways of each individual. Thus, a given concentration of amines can be tolerated by an organism with a normal catabolism, but it can cause harmful effects on a sensitive organism. In wines, the most important biogenic amines are histamine, tyramine, putrescine and cadaverine because they are the most abundant and can cause the greatest number of toxicological problems. Among the different types of wines, red wines have the highest content of biogenic amines. Also, in wines, the presence of ethanol increases the toxicological problems that can cause these biogenic amines because this alcohol inhibits or decreases the activity of amino oxidases responsible for their metabolism. In this project, the following biogenic amines have been considered: ethylamine, methylamine, dimethylamine, ethanolamine, butylamine, isobutylamine, isopentylamine and hexylamine. Although these amines are present at trace level, their study is important as possible descriptors of the health quality of food. To separate and determine them adequately the following studies have been carried out: ▪ A pre-column derivatization reaction has been performed with the 1,2-naphthoquinone-4-sulfonate reagent (NQS) to attach a chromophore group to the initial amines so that they could be detected with an ultraviolet-visible absorption detector. ▪ A liquid-liquid extraction process with chloroform as the solvent and subsequent evaporation until dryness has been used to obtain simpler chromatograms removing efficiently amino acid derivatives and other polar compounds that often interference with the chromatographic separation of biogenic amines, in addition to preconcentrating the extracts obtained. Combination of both derivatization and extraction procedures before the HPLC separation results in an effective clean-up of samples and affords a sensitive determination of biogenic amines. ▪ HPLC has been used as a technique for separating different amines under reversed-phase mode, optimizing the efficiency and resolution by modifying some variables such as the chromatographic column, the elution gradient or the separation temperature. It should be pointed out that due to the consequences of the global pandemic caused by the SARS-CoV-2 virus, significant parts of method optimization and validation studies as well as the analysis of wine and cava samples have not been finished