RESUMO
Scotch Whisky, a product of high importance to Scotland, has gained global approval for its distinctive qualities derived from the traditional production process, which is defined in law. However, ongoing research continuously enhances Scotch Whisky production and is fostering a diversification of flavour profiles. To be classified as Scotch Whisky, the final spirit needs to retain the aroma and taste of 'Scotch'. While each production step contributes significantly to whisky flavour-from malt preparation and mashing to fermentation, distillation, and maturation-the impact of yeast during fermentation is crucially important. Not only does the yeast convert the sugar to alcohol, it also produces important volatile compounds, e.g. esters and higher alcohols, that contribute to the final flavour profile of whisky. The yeast chosen for whisky fermentations can significantly influence whisky flavour, so the yeast strain employed is of high importance. This review explores the role of yeast in Scotch Whisky production and its influence on flavour diversification. Furthermore, an extensive examination of nonconventional yeasts employed in brewing and winemaking is undertaken to assess their potential suitability for adoption as Scotch Whisky yeast strains, followed by a review of methods for evaluating new yeast strains.
Assuntos
Bebidas Alcoólicas , Fermentação , Aromatizantes , Bebidas Alcoólicas/microbiologia , Bebidas Alcoólicas/análise , Aromatizantes/metabolismo , Leveduras/metabolismo , Leveduras/genética , Leveduras/classificação , Paladar , Escócia , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Compostos Orgânicos Voláteis/metabolismoRESUMO
Scotch Whisky is an important global commodity which generates extensive co-product known as pot ale or spent wash (> 10 L co-product per L whisky). Whilst this is often used as fertiliser or animal feed, a proportion requires disposal resulting in cost to the distillery along with the negative impact on the carbon footprint due to transportation. This study examined the composition of the soluble fraction of pot ale from twenty-two distilleries in Scotland in order to assess the potential for resource recovery and transition to a more circular economy. The results reinforced previous studies, demonstrating that pot ale is an excellent source of protein with a potential for recovery >150, 000 t per annum in Scotland based on Whisky production data. Lactic acid, an important industrial platform chemical, was the major organic acid produced with concentrations ranging from 0.3 to 6.6 g L -1, representing a potential opportunity for recovery for applications such as manufacture of biodegradable polylactic acid for plastics (> 15,000 t per annum based on mean values). Other important platform chemicals, succinic acid and lysine were also identified and considered in sufficient amounts for future use. Pot ale was also shown to contain significant amounts of critical raw materials, magnesium and phosphate, which could be reclaimed for use in fertiliser/feed supporting the development of a new circular economy whilst at the same time reducing the burden of mining and transportation on the environment. The data in this study demonstrated a potential 13.8 kt recoverable phosphate per annum representing more than half of the annual fertiliser consumption in Scotland. Whisky co-products can contribute to sustainable energy, food and platform chemicals with the added value that metal concentrations are not sufficiently high to prevent its utilisation.
RESUMO
Very little has been reported about the health resources available for patients with epilepsy in the five English-speaking southern Caribbean countries of Trinidad and Tobago, Barbados, Grenada, Saint Vincent and the Grenadines, and Saint Lucia. There is no comprehensive resource describing their health systems, access to specialty care, antiepileptic drug (AED) use, and availability of brain imaging and EEG. The purpose of this study was to profile epilepsy care in these countries as an initial step toward improving the standard of care and identifying gaps in care to guide future policy changes. In each southern Caribbean country, we conducted study visits and interviewed health-care providers, government health ministers, pharmacy directors, hospital medical directors, pharmacists, clinic staff, radiologists, and radiology and EEG technicians. Health-care providers completed extensive epilepsy care surveys. The five countries all have integrated government health systems with clinics and hospitals that provide free or heavily subsidized care and AEDs for patients with epilepsy. Only Trinidad and Tobago and Barbados, however, have neurology specialists. The three smaller countries lack government imaging and EEG facilities. Trinidad had up to one-year waits for public MRI/EEG. Government formularies in Grenada, Saint Vincent and the Grenadines, and Saint Lucia are limited to first-generation AEDs. One or more second-line agents are formulary in Trinidad and Barbados. Nonformulary drugs may be obtained for individual patients in Barbados. Grenada, Saint Lucia, and Saint Vincent and the Grenadines participate in an Organization of Eastern Caribbean States formulary purchasing system, which added levetiracetam following the survey. Newer generic AED formulations with the lowest risks for pregnancy malformation were not in use. In conclusion, patients with epilepsy in the southern Caribbean have excellent access to government clinics and hospitals, but AED choices are limited. Local medical providers reported that the major limitations in care were lack of specialty care, lack of imaging and EEG services, financial barriers to care, long wait times for care, and limited access to additional AEDs.
Assuntos
Atenção à Saúde/estatística & dados numéricos , Epilepsia/epidemiologia , Epilepsia/terapia , Anticonvulsivantes/provisão & distribuição , Barbados , Região do Caribe/epidemiologia , Países em Desenvolvimento , Uso de Medicamentos , Eletroencefalografia , Feminino , Formulários Farmacêuticos como Assunto , Pessoal de Saúde/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Neurologia/estatística & dados numéricos , Gravidez , Santa Lúcia , São Vicente e GranadinasRESUMO
In addition to ethanol yield, the production of flavour congeners during fermentation is a major consideration for Scotch whisky producers. Experimental whisky fermentations can provide useful information to the industry, and this is the focus of this paper. This study investigated the impact of wort pretreatments (boiled, autoclaved, filtered) on fermentation performance and flavour development in Scotch whisky distillates as an alternative to freezing wort for storage. Our study showed that no significant sensorial differences were detected in low wines (first distillates), while the chemical compositions showed clear changes in increased levels of esters and higher alcohols in boiled and autoclaved wort. In contrast, filtered wort comprised overall lower levels of congeners. Regarding alcohol yield, all three pretreatments resulted in decreased yields. In practice, the pretreatment of wort prior to fermentation requires additional process operations, while freezing requires large storage units. The pretreatments adopted in this study significantly influence the composition of the malt wort used for experimental whisky fermentations, and this results in a poorer fermentation performance compared with untreated wort. We recommend the use of fresh or frozen wort as the best options for small-scale fermentation trials.
RESUMO
In this study, ultra-violet (UV) and short-wave infra-red (SWIR) hyperspectral imaging (HSI) was used to measure the concentration of phenolic flavour compounds on malted barley that are responsible for smoky aroma of Scotch whisky. UV-HSI is a relatively unexplored technique that has the potential to detect specific absorptions of phenols. SWIR-HSI has proven to detect phenols in previous applications. Support Vector Machine Classification and Regression was applied to classify malts with ten different concentration levels of the compounds of interest, and to estimate the concentration respectively. Results reveal that UV-HSI is at its current development stage unsuitable for this task whereas SWIR-HSI is able to produce robust results with a classification accuracy of 99.8% and a squared correlation coefficient of 0.98 with a Root Mean Squared Error of 0.32â¯ppm for regression. The results indicate that with further testing and development, HSI may potentially be exploited in an industrial production environment.