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In recent years, the wine industry has been researching how to improve wine quality along the production value chain. In this scenario, we present here a new tool, MicroVi, a cost-effective chip-sized microscopy solution to detect and count yeast cells in wine samples. We demonstrate that this novel microscopy setup is able to measure the same type of samples as an optical microscopy system, but with smaller size equipment and with automated cell count configuration. The technology relies on the top of state-of-the-art computer vision pipelines to post-process the images and count the cells. A typical pipeline consists of normalization, feature extraction (i.e., SIFT), image composition (to increase both resolution and scanning area), holographic reconstruction and particle count (i.e., Hough transform). MicroVi achieved a 2.19 µm resolution by properly resolving the G7.6 features from the USAF Resolving Power Test Target 1951. Additionally, we aimed for a successful calibration of cell counts for Saccharomyces cerevisiae. We compared our direct results with our current optical setup, achieving a linear calibration for measurements ranging from 0.5 to 50 million cells per milliliter. Furthermore, other yeast cells were qualitatively resolved with our MicroVi microscope, such as, Brettanomyces bruxellensis, or bacteria, like, Lactobacillus plantarum, thus confirming the system's reliability for consistent microbial assessment. [ABSTRACT FROM AUTHOR]

Sparkling wines produced using the ancestral method, also known as Pét-Nats, are gaining more and more market share these days. However, scientific information on these wines is very scarce. The aim of this study was therefore to compare the physicochemical composition and sensory characteristics of a representative selection of commercial sparkling wines produced using the ancestral and traditional methods. Ancestral sparkling wines were more heterogeneous than traditional sparkling wines, as some of them showed lower internal pressure, higher turbidity, higher color intensity and lower effervescence. These differences are probably due to the fact that the protocol for making sparkling wines using the ancestral method is not as well defined as that for traditional sparkling wines. However, the ancestral method has the advantage of being able to work with riper grapes and a lower sulfur dioxide dosage. [ABSTRACT FROM AUTHOR]

This communication studies some possible strategies to reduce or even to replace sulfur dioxide in winemaking. Specifically, the aim of this work was to study the protective effect against oxidation of a commercial inactivated dry yeast (IDY) with very high level of glutathione, and of a selected non-Saccharomyces yeast, Metschnikowia pulcherrima strain in comparison with sulfur dioxide.

Digital histogram generation for time-resolved measurements with single-photon avalanche diode (SPAD) sensors requires the storage of many timestamp signals. This work presents a mixed-signal time-to-digital converter (TDC) that uses analog storage to achieve an area-efficient design that can be integrated in large SPAD arrays. Fabricated using a 150 nm CMOS process, the prototype occupies an area of only 18.3 µm × 36.5 µm, a notable size reduction compared to conventional designs. The experimental results demonstrated high performance, with an integral nonlinearity (INL) of 0.35/0.14 least significant bit (LSB) and a differential nonlinearity (DNL) of 0.14/−0.12 LSB. In addition, the proposed TDC can support the construction of histograms comprising up to 512 bins, making it an effective solution to accommodate a wide range of resolution requirements. Validated in a point-of-care (PoC) device for fluorescence lifetime measurements, it distinguished between lifetimes of approximately 4.1 ns, 3.6 ns and 80 ns with the Alexa Fluor (AF) 546 and 568 dyes and Quantum Dot (QD) 705, respectively. The analog storage design and area-efficient architecture offer a novel approach to integrating TDCs in SPAD-based systems, with potential applications in medical diagnostics and beyond. [ABSTRACT FROM AUTHOR]

Gamification is being incorporated into university classrooms due to its educational benefits for students learning, including encouraging student behavior and engagement, and consequently improving learning outcomes. Despite gamification being increasingly used in education, little has been developed related to Very-Large-Scale Integration (VLSI). In this article, we describe two different gamification experiences applied to integrated circuit processing and design in an introductory VLSI design course for Electronic Engineers. While gamification in universities is still not very mature and our experience spans only two academic years, we observed that, with the practice of gamifying part of our course, the topics treated in games were profoundly learned and the experience was very positive in every aspect of the teaching–learning process. [ABSTRACT FROM AUTHOR]

Nowadays, continuous monitoring is a difficult issue in microscopy. A chip-sized microscope was developed, composed only of microelectronic components, with high optical resolution and a wide field of view. Due to its miniaturized size, it can be placed on or attached to the sample for continuous monitoring in the sample environment. An example of an application of this microscope for the food and beverage industry is described, referring to the study of the fermentation process of white wine. The comparison of the images acquired with conventional optical microscopy reveals similar results. To automatically count yeast cells, the traditional image postprocessing is compared with deep learning. Neural networks achieve similar cell recognition characteristics but with an ~100× speed improvement, by directly processing the obtained holograms. [ABSTRACT FROM AUTHOR]

La Gomera Island is one of the areas of our planet where the phylloxera plague never arrived. To measure the genetic diversity of the vine after more than 500 years (inter- and intravarietal variability) of adaptation to this new environment, a prospection was carried out. For this purpose, 120 samples were collected and genotyped with 20 SSRs. A total of 52 unique profiles were found corresponding to 4 new varieties (Coello blanca, Barrerita negra, Malvasia periquin gomerae, Verdello gomerae), 9 individuals identical to the most widespread profile, and 39 individuals that presented variations (1 corresponding to a mutation of a new variety (Verdello gomerae de Monacal) and 38 corresponding to variations of known varieties, some of which included cases of triallelism or quadriallelism). The population of local vines in La Gomera Island is considered to be the most unique in the Canary Islands to date. It is hypothesised that the grapevine varieties Malvasia periquin gomerae and Verdello gomerae are possibly the most unique and that the Barrerita negra variety may have resulted from an interspecific crossbreeding. The Coello blanco variety (admixed) seems to have a strong Central European influence. Finally, we propose that the prime name for the Albillo forastero variety, which was arbitrarily imposed by the scientific community, be changed to the more widespread and better-known name in La Gomera Island and the Canary Archipelago, which is Forastera gomerae. [ABSTRACT FROM AUTHOR]

A prospection was carried out on Fuerteventura Island in order to explore the existing biodiversity of Vitis vinifera ssp. vinifera in almost desert conditions (<120 mm per year). For this purpose, 40 individuals were collected and genotyped with 20 SSRs. Nine known varieties and one unknown variety, named Majorera on the island, were identified. In addition, four new mutations were found in the varieties Listan negro and Listan prieto, respectively. Thirteen unknown individuals and five erratic accessions were identified. Seven new names are proposed for inclusion in the world databank (one main name (Majorera), one new synonym for Listan negro (Hoja moral), four new mutation names (Listan prieto de Antigua, Listan prieto de Vega, Hoja moral de El Rosario and Hoja moral de Betancuria) and a new synonymy for Muscat Hamburg (Moscatel), which is very widespread on the island). Finally, the possibility is raised that the new Majorera variety is not a pure vinifera but the product of an interspecific cross, as has happened with the variety found on the island of La Palma, Bienmesabe tinto. Once again, the Canary Archipelago shows itself to be a possible centre for the creation of biodiversity for the cultivated vine. [ABSTRACT FROM AUTHOR]

El Hierro island is postulated as the most biodiverse of the archipelago. To verify this hypothesis, the 87 individuals collected throughout the island were genotyped with 20 SSRs. As a result of this study, 28 varieties were described, 6 of which were new (Uval piñero, Uvalero volcánico, Pinar negro, Seis de Carlos, Tesoro blanco, Uval negro), and the first rose sport of the local Canary Islands variety Bermejuela was also found. Fifteen errors were detected in total. Eleven varieties were identified that were unknown to the vine growers and twenty individuals with variations (mutations) were found, of which two had already been described in a previous prospection in Lanzarote Island (intra-varietal variability). From this study, it is also proposed to incorporate 33 new names into the world database, corresponding mostly to the individuals and variations described for the first time, which represents a lexicographic enrichment. Finally, the singularity of the population of vines adapted to El Hierro island is demonstrated, not only with respect to the population of Canary Islands vines, but also with respect to the world population. The biodiversity and uniqueness of El Hierro and the Canary Archipelago reaffirm the proposal that the Canary Islands should be considered a world biodiversity centre. [ABSTRACT FROM AUTHOR]

This study investigates the impact of inoculating Torulaspora delbrueckii (Td) strains during the initial phase of carbonic maceration (CM) vinification, aiming to enhance the fermentative process and unique characteristics of CM wines. CM is a winemaking technique where whole bunches (without destemming and crushing) are enclosed in tanks filled with carbon dioxide, inducing intracellular fermentation. This study compares the effects of two Td strains on the MLF performance and sensory characteristics of CM wines using both inoculated and spontaneous MLF strategies. Although general physicochemical parameters remained consistent across conditions, organoleptic attributes showed significant differences due to T. delbrueckii presence. T. delbrueckii introduction during CM resulted in wines with increased anthocyanin content and a particular volatile profile. Isoamyl acetate, a key aroma in CM wines, was notably elevated, especially in the TdP strain. Sensory evaluations also revealed distinctions, with TdV wines displaying more pronounced aromas of red fruit, banana, and grass. Regarding MLF, T. delbrueckii presence notably enhanced performance, particularly in spontaneous MLF cases, accelerating fermentation completion. Inoculating the Oenococcus oeni strain OoVP41 also shortened MLF duration. These findings highlight the potential of Td strains to improve MLF efficiency and sensory attributes in CM wines. Using T. delbrueckii strains strategically enables winemakers to optimize MLF and improve sensory profiles, offering an opportunity to produce higher-quality CM wines. [ABSTRACT FROM AUTHOR]