A fast and low-cost approach for the discrimination of commercial aged cachaças using synchronous fluorescence spectroscopy and multivariate classification.

BACKGROUND: Cachaça is the distilled beverage typical of Brazil and can be subjected to the aging process in wooden barrels. In addition to oak barrels, cachaça is also aged in barrels of different Brazilian native woods, resulting in a wide variety of its sensory characteristics. In this work, 172 cachaças aged in bálsamo, jequitibá, oak, and umburana barrels were analyzed by synchronous fluorescence spectroscopy and by the classification methods of principal component analysis and partial least squares discriminant analysis. Spectra were preprocessed by the first derivative by Savitzky-Golay smoothing, using a filter width and polynomial order determined through face-centered central composite designs. Multivariate analysis was realized using the spectra recorded at different wavelength differences, and models were compared by the classification errors in the test sets. RESULTS: The principal component analysis applied to the synchronous fluorescence spectra presented a tendency of separation by the wood used in the aging process, and the partial least squares discriminant analysis model constructed using the fluorescence spectra recorded at a wavelength difference of 30 nm provided better performance parameters (efficiency 91-97%, sensitivity 81-100%, and specificity 91-100%). CONCLUSION: Synchronous fluorescence spectroscopy offers a promising approach for the classification of cachaças aged in bálsamo, oak, jequitibá, and umburana barrels, and the discriminant model can be used for routine analysis as a screening method. © 2022 Society of Chemical Industry.

Temporal dominance of sensations and preferences of Brazilians and Slovakians: A cross-cultural study of cachaças stored with woods from the Amazon rainforest.

BACKGROUND: Brazilians and Slovakians evaluated the temporal profile and the acceptability of cachaça stored with different woods (Cumarurana (CM), Jatobá (JT) and, Louro-vermelho (LV), which are found in the Amazon rainforest, and also oak), with the aim of performing a cross-cultural comparison of the dynamic profile of the attributes perceived in the cachaças and the sensorial acceptance of the samples. RESULTS: Important differences were observed between the temporal sensorial profiles generated by the two groups and their preferences. Brazilians preferred cachaças stored with the traditional wood, oak, followed by those stored with JT and CM. In contrast, Slovakians preferred cachaças stored with JT, followed by those stored with LV and oak. For both countries, the dominance of wood flavor and vanilla attributes at the end of the analysis time was positively associated with acceptance, while the dominance of off-flavors and the wood flavor attribute at the beginning of the analysis time was negatively associated with acceptance for Brazilians and Slovakians, respectively. CONCLUSION: Brazilians preferred cachaça stored with oak wood, and Slovakians preferred cachaça stored with JT wood, with acceptability being strongly associated with the dominance of wood flavor and vanilla attributes at the end of the evaluation time. © 2018 Society of Chemical Industry.

Uses, Knowledge and Extinction Risk Faced by Agave Species in Mexico.

We compiled an updated database of all Agave species found in Mexico and analyzed it with specific criteria according to their biological parameters to evaluate the conservation and knowledge status of each species. Analyzing the present status of all Agave species not only provides crucial information for each species, but also helps determine which ones require special protection, especially those which are heavily used or cultivated for the production of distilled beverages. We conducted an extensive literature review search and compiled the conservation status of each species using mainstream criteria by IUCN. The information gaps in the database indicate a lack of knowledge and research regarding specific Agave species and it validates the need to conduct more studies on this genus. In total, 168 Agave species were included in our study, from which 89 are in the subgenus Agave and 79 in the subgenus Littaea. Agave lurida and A. nizandensis, in the subgenus Agave and Littaea, respectively, are severely endangered, due to their endemism, lack of knowledge about pollinators and floral visitors, and their endangered status according to the IUCN Red List. Some species are at risk due to the loss of genetic diversity resulting from production practices (i.e., Agave tequilana), and others because of excessive and unchecked overharvesting of wild plants, such as A. guadalajarana, A. victoriae-reginae, A. kristenii, and others. Given the huge economic and ecological importance of plants in the genus Agave, our review will be a milestone to ensure their future and continued provision of ecosystem services for humans, as well as encouraging further research in Agave species in an effort to enhance awareness of their conservation needs and sustainable use, and the implementation of eco-friendly practices in the species management.

Synchronous fluorescence spectroscopy and multivariate classification for the discrimination of cachaças and rums.

Although cachaça and rum are distilled beverages obtained from the same raw material, they present differences in their chemical compositions. In this study, synchronous fluorescence spectroscopy was used combined with supervised classification models based on the partial least squares discriminant analysis to develop a rapid and low-cost model for discriminating between 50 cachaça and 40 rum samples. Partial least squares discriminant analysis models were constructed using synchronous fluorescence spectra recorded at wavelength differences of 10-100 nm. Initially, spectra were preprocessed by the first derivative with the Savitzky-Golay smoothing, and filter width and polynomial order were selected through face-centered central composite designs. For the construction and validation models, the spectra data were split into two datasets: the training and the test sets containing 60 (C, n = 33; R, n = 27) and 30 (C, n = 17; R, n = 13) samples, respectively. The best discrimination was achieved using fluorescence spectra recorded at wavelength difference 10 nm, allowing the discrimination of cachaça and rum with a classification efficiency of 98%. These results indicate that synchronous fluorescence spectroscopy offers a promising approach for the authentication of cachaças and rums.

A color reaction for the determination of Cu2+ in distilled beverages employing digital imaging.

In this work, we describe for the first time the synthesis of a thiocarbazone for the selective determination of Cu2+ in distilled beverages. The method was based on the complexation reaction of Cu2+ with the thiocarbazone, and the colored product was analyzed using a smartphone application. The thiocarbazone reacts with Cu2+ to form a 1:1 (metal:ligand) complex. The Cu2+ complex was characterized by UV, IR and NMR spectral analyses. The proposed reaction yields a yellow color, and therefore, channel B of the RGB system was used in the analysis. After optimizing the reaction conditions, an analytical curve was obtained to determine Cu2+ concentrations ranging between 0.25 and 6.75 mg L-1; the use of 400 µL sample volumes led to a relative standard deviation (n = 5) of 3.2% and a detection limit of 0.18 mg L-1. Recovery experiments were performed with sugar cane spirits, whiskies and tequilas to evaluate the accuracy of the method, and the recovery obtained ranged from 80.5 to 112.2%.

Morphological and Genetic Variation in Monocultures, Forestry Systems and Wild Populations of Agave maximiliana of Western Mexico: Implications for Its Conservation.

Forestry systems in Mexico are examples of traditional management of land and biodiversity that integrates the use, conservation and restoration of forest elements. Current in situ management practices of Agave maximiliana in western Mexico include the tolerance of many forest elements, reintroduction of young Agave plants and germination of seeds. More intense forms of management include monocultures, which are agroindustrialized systems developed in more recent times and characterized by the establishment of high densities of A. maximiliana plants in deforested areas and abandoned agricultural lands. We compared monocultures, forestry systems and wild populations (i.e., non/slightly-exploited forests) in order to evaluate whether these practices have had an effect on intraspecific morphological and genetic variation and divergence. We also tested whether divergence has a positive relationship with environmental and geographic distance. We analyzed 16 phenotypic traits in 17 populations of A. maximiliana, and 14 populations were further examined by amplifying 9 SSR loci. We employed multivariate methods and analyses of variance in phenotypic and genetic traits to test whether clusters and the percentage of variation contained in the managed and wild categories can be identified. Tests of isolation by environment (IBE) and distance (IBD) were performed to detect the magnitude of divergence explained by climatic and geographic variables. We found that forestry systems are effective as reservoirs of morphological and genetic diversity, since they maintain levels similar to those of wild populations. Moreover, the monocultures showed similar levels, reflecting their recent emergence. While the species showed high morphological diversity (IMD = 0.638, SE ± 0.07), it had low to intermediate genetic diversity (A = 2.37, H E = 0.418). Similar morphological and genetic divergences were found among populations, but these were not correlated with each other in population pairs. Non-significant morphological differentiation was found among categories. Only IBE was significant in the genetic structure (ß = 0.32, p = 0.007), while neither IBE nor IBD was detected in the morphological differentiation. We discuss the implications of these results in the context of the weaknesses and strengths of A. maximiliana in the face of the socio-ecological changes predicted for the study area in the short term.

Flow thermal infrared enthalpimetry: Rapid and inexpensive determination of the alcohol content of distilled beverages.

In this work, a simple and inexpensive flow thermal infrared enthalpimetry (TIE-F) method was developed through a combination of flow injection analysis and thermal infrared enthalpimetry (TIE) to determine the alcohol content of distilled beverages (cachaça, cognac, and vodka). The principle used in this method consisted of monitoring the enthalpy of dissolution of ethanol through a low-cost infrared sensor coupled to a flow system. The results showed an agreement between the proposed method and the conventional method, ranging from 96.5% to 99.0%. The obtained limit of quantification (LOQ, 10σ) of 25.10% (v/v) was enough for distilled beverages, which should present a minimum alcoholic content of 36% according to Brazilian legislation. In addition, the TIE-F instrumentation presented costs that were 100 times lower than the instrumentation that was used in the batch TIE, and the time of analysis was significantly reduced. The amount of residue generated was also reduced, thereby providing significant energy savings and easy adaptation to processes on industrial scales.