First Study of Sourdough Beer Aging Via the Chemical Fingerprint of Volatile Markers

'Ghost Boats' in Venice: Environmental concerns, green chemical fingerprint, circular and sustainable end-of-life-solutions

Venice is one of the most iconic and massively visited landscape in the World. Leisure and freight boats are extremely needed, yet no one has foreseen their after-life treatment. Those abandoned, turning to the status of 'ghost boats', undergo weathering and progressively fragment into scraps generating microplastics, fiberglass dusts or asbestos. We tackle this problem via a multiple level citizen involving chemistry students, personnel assigned for Public Utility Work by the Venice court, and SMEs within the sustainable business concept of the Triple Bottom Line (Planet, People, Profit). For the very first time an analytical procedure was optimized to scrutinize the leaching of a variegated assortment of chemicals from the abandoned boats into the marine environment via a green analytical approach (AGREE Prep score 0.8, Analytical Eco-scale score 91). We studied its contamination at the molecular level, via HS-SPME-GC-MS, deciphering the volatiles fingerprint of three representative kind of samples (water, soil, and mud) in a remote environment of the Venice Lagoon, contaminated by decaying fiberglass boats. We developed hypotheses on the origin of each identified analyte, taking into account that the most common construction materials are fiberglass reinforced plastic and polyurethane foams and coatings. Among the forty-three positively identified analytes, fifteen identified analytes are related to polymers chemistries. The chromatographic signatures of the volatile organic compounds are dominated, in all cases, by polyurethane related markers, such as isocyanates and polyols. This can be rationalized by the pervasive presence of polyurethane in recreational boats due to its high thermal and electrical resistance, low weight, rigidity or flexibility. Seventeen analytes come from the biotic environment. Fossil fuels volatiles, pharmaceuticals and other common chemicals were also detected. Among them, sarcosine, ethanolamine, methoxy-phenyl oxime, and phytone are specific to the marine biotic environment. Many plant volatiles can also have an anthropic origin as they are widely used in personal care products and cleaning agents, According to a Precautionary Principle, this study prompts the removal of these 'ghost boats' for environmental and health reasons, beyond aesthetics and safety motivations. It sheds lights on the origin of the problem from the governance level and it recommends solutions. Finally, it draws insights from an operational sustainable circular economy model preventing the contamination of the biosphere by the plastisphere, showcasing a repurposing of 'ghost boats' with carbon negative emissions certified by an Environmental Product Declaration.

Derivatization Strategies in Flavor Analysis: An Overview over the Wine and Beer Scenario

Wine and beer are the most appreciated and consumed beverages in the world. This success is mainly due to their characteristic taste, smell, and aroma, which can delight consumer’s palates. These olfactory characteristics are produced from specific classes of volatile compounds called “volatile odor-active compounds” linked to different factors such as age and production. Given the vast market of drinking beverages, the characterization of these odor compounds is increasingly important. However, the chemical complexity of these beverages has led the scientific community to develop several analytical techniques for extracting and quantifying these molecules. Even though the recent “green-oriented” trend is directed towards direct preparation-free procedures, for some class of analytes a conventional step like derivatization is unavoidable. This review is a snapshot of the most used derivatization strategies developed in the last 15 years for VOAs’ determination in wine and beer, the most consumed fermented beverages worldwide and among the most complex ones. A comprehensive overview is provided for every method, whereas pros and cons are critically analyzed and discussed. Emphasis was given to miniaturized methods which are more consistent with the principles of “green analytical chemistry”.

Fermented Minor Grain Foods: Classification, Functional Components, and Probiotic Potential

Fermented minor grain (MG) foods often have unique nutritional value and functional characteristics, which are important for developing dietary culture worldwide. As a kind of special raw material in fermented food, minor grains have special functional components, such as trace elements, dietary fiber, and polyphenols. Fermented MG foods have excellent nutrients, phytochemicals, and bioactive compounds and are consumed as a rich source of probiotic microbes. Thus, the purpose of this review is to introduce the latest progress in research related to the fermentation products of MGs. Specific discussion is focused on the classification of fermented MG foods and their nutritional and health implications, including studies of microbial diversity, functional components, and probiotic potential. Furthermore, this review discusses how mixed fermentation of grain mixtures is a better method for developing new functional foods to increase the nutritional value of meals based on cereals and legumes in terms of dietary protein and micronutrients.

Scent of knowledge: The molecular fingerprint of volatiles in an emblematic historical library in Italy

Heritage guidelines recognize odors as a value associated with a place. This study aims to clarify the connection between heritage and volatile organic compounds at the molecular level. At variance with previous studies, usually focused only on book-related compounds from accelerated degradation tests, the whole air of one of the most significant historical libraries in Italy was studied. A sampling of the volatiles off-gassing from the two most iconic rooms, respectively open and forbidden to visitors, was performed via a non-invasive, nondestructive green method, solid-phase-micro-extraction. The gas-chromatographic analyses resulted in the appraisal of olfactory contributions from books, storage environment, and, for the first time, anthropic activities and pollution.Concerning the paper decay process, for the very first time, the presence of 2-ethyl-1-hexanol in the chromatographic signature of the library air is rationalized according to the Guerbet reaction. The presence of all other compounds is explained by the paper decay process, anthropic sources, and pollution. Indoor air comprises analytes related to paper decay, identified by previous studies, and additional compounds never found before.Most volatile compounds are aliphatic and aromatic hydrocarbons, aldehydes, alcohols, terpenes, and terpenoids. Odor contributions from a selected number of analytes were pinpointed. Alkanes dominate the volatiles chromatographic signature, and impart a slight hydrocarbon smell. Aromatics supplement their characteristic aromatic odor. Aldehydes' very low odor threshold makes them strongly contribute to both fruity and fatty descriptors. Benzaldehyde, furfural, vanillin, and camphor add, respectively, an hint of almond, bread, vanilla, and camphor. Alcohols such as 2-ethyl hexanol have a floral scent. Wood-related terpenes and terpenoids contribute to the woody smell of the library.The digital molecular fingerprint of the "scent of knowledge" enables documentation, conservation, and future chemical reproduction of the historical library odor.

Analysis of volatiles organic compounds in Venice lagoon water reveals COVID 19 lockdown impact on microplastics and mass tourism related pollutants

The Lagoon of Venice is a continuously evolving ecosystem that rapidly responds to anthropic stressors. The UNESCO World Heritage site "Venice and its Lagoon", is one of the top tourist destinations in the world. Mass tourism increases marine litter, water traffic emissions, solid waste, and sewage release. Plastic marine litter is not only a major aesthetic problem diminishing tourists experience of Venice, it also leaches contaminants into the seawater. Since there is a dearth in the literature regarding microplastic leachable compounds and overtourism related pollutants, the project studied the Head Space-Solid Phase Micro Extraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS) molecular fingerprint of volatile lagoon water pollutants, to gain insight into the extent of this phenomenon in August 2019. The chromatographic analyses enabled the identification of 40 analytes related to the presence of polymers in seawater, water traffic, and tourists habits. In Italy, on the 10th March 2020, the lockdown restrictions were enforced to control the spread of the SARS-CoV-2 infection; the ordinary urban water traffic around Venice came to a halt, and the ever-growing presence of tourists suddenly ceased. This situation provided a unique opportunity to analyze the environmental effects of restrictions on VOCs load in the Lagoon. 17 contaminants became not detectable after the lockdown period. The statistical analysis indicated that the amounts of many other contaminants significantly dropped. The presence of 9 analytes was not statistically influenced by the lockdown restrictions, probably because of their stronger persistence or continuous input in the environment from diverse sources. Results signify a sharp and encouraging pollution decrease at the molecular level, concomitant with the anthropogenic stress release, even if it is not possible to attribute quantitatively the VOCs load variations to specific sources (e.g., tourists' habits, urban water traffic, plastic pollution).

Autochthonous Biological Resources for the Production of Regional Craft Beers: Exploring Possible Contributions of Cereals, Hops, Microbes, and Other Ingredients

Selected biological resources used as raw materials in beer production are important drivers of innovation and segmentation in the dynamic market of craft beers. Among these resources, local/regional ingredients have several benefits, such as strengthening the connection with territories, enhancing the added value of the final products, and reducing supply costs and environmental impacts. It is assumed that specific ingredients provide differences in flavours, aromas, and, more generally, sensory attributes of the final products. In particular, of interest are ingredients with features attributable and/or linked to a specific geographical origin. This review encompasses the potential contribution and exploitation of biodiversity in the main classes of beer inputs, such as cereals, hops, microbes, and adjuncts, with a specific emphasis on autochthonous biological resources, detailing the innovative paths already explored and documented in the scientific literature. This dissertation proposes an overview of the impact on beer quality for each raw material category, highlighting the benefits and limitations that influence its concrete applications and scale-up, from the field to the stain. The topics explored promote, in the sector of craft beers, trends already capitalised in the production of other alcoholic beverages, such as the preservation and revalorisation of minor and autochthonous varieties, the exploitation of yeast and bacteria strains isolated from specific sites/plant varieties, and the valorisation of the effects of peculiar terroirs on the quality of agricultural products. Finally, the examined tendencies contribute toward reducing the environmental impacts of craft beer manufacturing, and are in line with sustainable development of food systems, increasing the economic driver of biodiversity preservation.

Novel microencapsulated yeast for the primary fermentation of green beer: kinetic behavior, volatiles and sensory profile

The development of innovative and more cost-effective approaches of making beer throughout continuous fermentation process remains a challenging problem, which is worthy of serious exploration. The current work focuses on the application of a commercial brewing yeast (S. cerevisiae Nottingham Ale), entrapped into chitosan-calcium alginate double layer microcapsules, for the production of a Pale Ale beer. During the primary alcoholic fermentation, the consumption rate of fermentable brewing sugars and dissolved O₂, estimated by the Gompertz equation, was halved in the beer obtained by encapsulated yeast in comparison with the free cell. The physical-chemical parameters of beer (i.e. pH, alcohol content, color and bitterness) were not remarkably affected by the different yeast-inoculating form. However, the volatile profiles identified by means of HS-SPME-GC-MS analysis, significantly differed in terms of terpenes, esters and alcohols content, thus proving that the yeast-inoculating form may typify the odor and flavor descriptors of the green beer.