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Aroma features of Hanseniaspora vineae Hv205 wines in sequential and co-inoculation strategies
Get PDFHanseniaspora vineae (Hv) is a non-Saccharomyces yeast with unique metabolic features, making it appealing for wine production. However, Hv presents high nutritional requirements that may lead to slow fermentation. This study investigated the impact of sequential inoculation of Saccharomyces cerevisiae (Sc) in white winemaking at different time points (24, 48, 74, 100 and 200 h) during Hv fermentation and compared them to simultaneous inoculations. The 200 h protocol extended fermentation by an average of 13 days compared to pure Sc, decreasing with earlier sequential inoculation. Sc wines were richer in isoamyl acetate and ethyl hexanoate than Hv wines, with no significant differences among inoculation protocols. beta-phenylethyl acetate was increased in Hv wines, particularly in the 24 h protocol. The 2-phenylethanol concentration was negatively correlated with the S. cerevisiae inoculation delay. Hv altered the wine aroma features, enhancing the compounds associated with rose-like scents. Reducing the Sc inoculation delay aligned Hv with industrial standards while maintaining increased beta-phenylethyl acetate production. However, co-inoculation with Sc seems to better meet the Hv requirement without sacrificing the main aromatic features of Hv, demonstrating faster sugar depletion and higher acetate and ethyl ester contents, suggesting that co-inoculation yields a more modulable wine aroma profile
Alpine grazing management, breed and diet effects on coagulation properties, composition, and microbiota of dairy cow milk by commercial mountain based herds
Get PDFCow milk microbiota has received increased attention in recent years, not only because of its importance for human health but also because of its effect on the quality and technological properties of milk. Several studies, therefore, have investigated the effect of various production factors on the microbial composition of milk. However, most of the previous studies considered a limited number of animals from experimental or single farm, which could have biased the results. Therefore, this study aimed to understand the effect of different alpine production systems on the compositional and microbiological quality of milk, considering commercial herds with different feeding intensities and cattle breeds. The results obtained in this work indicated that the month/season of sampling (July for summer or February for winter) more than farm, breed and cow diet exerted significant effects on cow milk parameters and microbiota. In particular, significant differences were observed for urea content in milk between sampling seasons. Differences in milk fat were mainly related to breed specific effects. From a microbiological point of view, statistically significant differences were found in presumptive lactic acid bacteria counts. Based on a culture-independent method, milk obtained in February harbored the highest number of Firmicutes (e.g., Lactobacillus) and the lowest number of Actinobacteria (e.g., Corynebacterium). Moreover, bacterial richness and diversity were higher in July/summer during alpine pasture season indicating a significant effect of pasture feed on the growth of bacterial communities. The results of this study highlighted the effect of month/season mainly related to differences in feeding management (e.g., access to pasture during vegetation period, concentrates supplementation) on composition and microbiota in milk
Toxins of freshwater microorganisms: from bio- to chemodiversity
No full textCyanobacteria are prokaryotic microorganisms that are present in all freshwater environments. A certain number of cyanobacterial species have the ability of producing toxic secondary metabolites. The massive growth (or bloom) of toxigenic cyanobacteria can lead to high concentrations of toxins in the water, thus posing a threat to human health. Eutrophication is the main driver of cyanobacterial blooms, but ongoing climate changes can exacerbate the problem. Cyanobacterial toxins (cyanotoxins) are secondary metabolites with a huge chemical diversity due to the high flexibility of their biosynthetic pathways.1 Research conducted in the last fifteen years at Fondazione Edmund Mach has revealed that the biosynthetic pathways are common to all toxigenic cyanobacteria, but that the resultant toxic molecules are very dependent on the species.2 For instance, the cyanobacteria Planktothrix rubescens and Microcystis aeruginosa (among the most frequent responsible of toxic blooms around the world) both have the same gene cluster of the hepatotoxic microcystins (MC), but they synthetize different variants of MC. Moreover, the same set of MC are produced in different ratios by different strains of P. rubescens. These examples show how an integrated biological and chemical approach can be very effective in studying toxigenic cyanobacteria. This approach has demonstrated to be very useful in addressing the toxic potential of populations of cyanobacteria in different natural lakes.3 The presence of cyanotoxins in freshwaters is a matter that is taken into consideration by legislation in most countries and specific monitoring programs are routinely carried out by sanitary/environmental agencies. An emerging issue that is not yet considered by legislation is the presence of toxic cyanobacteria attached to different types of substrates (rocks, stones, vegetation) on the shores of lakes and rivers. Our recent studies revealed that some potent neurotoxins (anatoxins) can be produced in very high quantities by cyanobacteria growing in these environments. Such “biofilms” can constitute a relevant sanitary problem, considered that they can be easily accessed by people and animals walking on the shores
Environmental impact of different Mediterranean technological systems for European sea bass (Dicentrarchus labrax) and Gilthead sea bream (Sparus aurata) farming
No full textAs at a global level, the aquaculture sector is growing in Italy too and, among the various species, European sea bass and Gilthead sea bream are becoming increasingly important. As a consequence, the environmental implications are an emerging issue and in-depth studies on the topic of farm sustainability are needed. This study compared the environmental performance of four specialised Sea bass and Sea bream farms in Italy, characterized by different technological system, using the Life Cycle Assessment approach. 1 tonne of fish biomass harvested and 1 kg of fish protein were chosen as functional units. The 'from cradle to gate' perspective was applied to define the system boundaries. The results revealed that land-based farms had higher environmental impacts compared to coastal farm with a Climate change of 9660 and 7250 kg CO2 eq for the former and 2443 and 3308 for the latter. Despite the use of aquafeeds emerged as a significant contributor of environmental impacts across all farms (with a share of more than 80 % of the Climate change in the coastal farms), even energy and liquid oxygen consumption, particularly on land-based farms, played a crucial role (with impact shares of 25–40 % in climate change). A sensitivity analysis on energy sources revealed that the use of more renewable energy can reduce the Climate Change of land-based farms by an average of 5 %, while an all-biodiesel fleet has a beneficial effect on particulate matter (-7.5 %) and acidification (-6 %) on coastal farms. The study provided a comprehensive overview of the environmental impact of Italian ESB and GSB production. In addition, highlighted areas for further research, including biofouling mitigation, optimization of energy consumption, and exploration of alternative oxygenation methods in land-based farm
Characterization of the natural vanilla samples of different botanical and geographical origin based on the aromatic profile
No full textVanilla is one of the most popular flavouring agents in various foods, beverages, pharmacies, and cosmetics. Natural sources of the vanilla flavour are the pods of tropical orchid plants: Vanilla planifolia, Vanilla tahitensis, and Vanilla pompona. Vanilla planifolia is the most widely traded species followed by Vanilla tahitensis. Although the characteristic vanilla aroma is mainly due to vanillin (4-hydroxy-3-methoxybenzaldehyde), the vanilla pods consist of many other volatile compounds. Like vanillin, ethyl vanillin (3-ethoxy-4-hydroxybenzaldehyde), which is 3 to 4 times more intense than vanillin, is also widely used as a less expensive flavouring agent than vanilla extracts to imitate or enhance the vanilla aroma. Currently, all ethyl vanillin supplied to the global market is produced by chemical catalysis, and up to now the presence of ethyl vanillin in natural vanilla extracts has not been reported yet. The aim of this study was to characterize the aroma profiles of vanilla pod extracts in order to discriminate between different geographical origins and different botanical species. Ten vanilla samples from Madagascar, Mexico, French Polynesia, Papua New Guinea and La Réunion were collected. These samples were of two different botanical species: Vanilla planifolia and Vanilla tahitensis. The hydroalcoholic extracts were analysed by GC-MS/MS and about 50 volatile organic compounds (VOCs) belonging to different chemical classes were quantified. The different content of VOCs was able to distinguish the two botanical species, but not the geographical origins. Moreover, the GC-MS/MS analysis did not detect ethyl vanillin above the detection limit in any of the vanilla pod samples. The absence of ethyl vanillin in vanilla pods was also confirmed by researching its glycosylated precursor by means of UHPLC-HRMS
Mammals show faster recovery from capture and tagging in human-disturbed landscapes
Get PDFWildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4-7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammal
Exploring the role of trust in novel foods, food neophobia and emotions in the visual liking of red-fleshed apples
No full textTechnological affinity index for interaction between lactic acid bacteria and Saccharomyces cerevisiae strains to modulate the fruity and floreal aroma of Catarratto wines
No full textMicrobial interactions during the fermentation process influence the sensory characteristics of wines. Alongside alcoholic fermentation, malolactic fermentation also plays a crucial role in determining the aromatic traits of wines. The time (t), rate (m) and volatile organic compounds (VOCs) of malolactic fermentation are linked to the interaction between yeasts and lactic acid bacteria. The study investigated the interactions between Lactiplantibacillus plantarum or Oenococcus oeni with Saccharomyces cerevisiae by using the Technological Affinity Index (TAIndex). The co-inoculation of L. plantarum/S. cerevisiae resulted in a higher TAIndex than the co-inoculation of O. oeni/S. cerevisiae conditions. A low TAIndex led to increased aromaticity of the wines. The time and rate of malolactic fermentation have a strong impact on the synthesis of VOCs with a high olfactory impact. Therefore, knowledge of the TAIndex could play a decisive role in improving winemaking planning to produce wines with higher fruit and floral perception
Digitalization and valorization of the genotypic and phenotypic information retained within the FEM grapevine germplasm
Get PDFThe maintenance and valorization of genetic diversity is an undoubtable resource for the viticulture of the future, since the climate crisis is forcing us to think of new, more resilient varieties. For this reason, the grapevine germplasm of the Fondazione Edmund Mach has been continuously expanded in the last decade to a total of 3,120 accessions, whose trueness-to-type has been verified by means of the universal set of nine microsatellites. About two thirds are V. vinifera subsp. vinifera accessions, while the rest consists of naturalized and selected hybrids, V. vinifera subsp. sylvestris, and pure species. The genetic material has also been characterized over three consecutive years for ampelographic, vine development, and biotic stress response traits to be exploited for experimental purposes. All the data and metadata have been digitalized and hosted in a SQL database, the FEMVitisDB, developed with an ontology driven paradigm to annotate the deposited information. The database was built following the MIAPPE checklist to ensure data FAIRness. A RESTful WebServiceAPI based on BrAPI and a web frontend were developed to easily explore the information in the repository. Findings about the captured genetic diversity, the identified unique profiles, and the scouted unknown and therefore novel genotypes will be discussed. The latter enrich the genetic asset of the grapevine community, towards the feeding of international databases. Where feasible, the first degree of parentage relationship has been reconstructed. Finally, the outcomes regarding the inferred phenological core collections will be introduced to provide an information arsenal for future ’omics analyses