Search results for "Hanse"
showing 10 items of 47 documents
Exponential growth phase cells of the osmotolerant yeast Debaryomyces hansenii are extremely resistant to dehydration stress
2001
Abstract The osmotolerant yeast Debaryomyces hansenii is highly resistant to dehydration stress and this tolerance was more pronounced for cells taken from the exponential growth phase than from the stationary phase. Growth of D. hansenii in medium containing 10% (w v −1 ) NaCl, resulted in an additional increase in cellular resistance to dehydration, which was most marked for stationary phase cells. It is expected that further investigations of the mechanisms behind this exceptional dehydrational tolerance will reveal new approaches for improvement of the quality of dry yeast.
Evolution of microbiological and chemical parameters during red wine making with extended post-fermentation maceration.
2014
Abstract The aim of the present work was to investigate the microbiological, chemical, and sensory characteristics of red wine subjected to post-fermentation maceration that was extended to 90 days. For this purpose, the ‘Aglianico di Taurasi’ grape was used as a case study. The total yeast concentration increased until day 40 of maceration and decreased thereafter, whereas the concentration of lactic acid bacteria slightly increased. Dekkera/Brettanomyces spp. and acetic acid bacteria were not detected. The yeast community was composed of Saccharomyces cerevisiae, Zygosaccharomyces bisporus, Metschnikowia pulcherrima, Hanseniaspora guilliermondii, Hanseniaspora uvarum, Pichia guilliermondi…
Building up a multilateral strategy for the United States: Jacob Viner, Alvin Hansen and the Council on Foreign Relations (1939-1945)
2009
Increasing the levels of 2-phenylethyl acetate in wine through the use of a mixed culture of Hanseniaspora osmophila and Saccharomyces cerevisiae
2009
The impact of mixed cultures of Hanseniaspora osmophila and Saccharomyces cerevisiae with different initial yeast ratios on wine composition has been examined. The mixed culture significantly affected sugar consumption, the main enological parameters and ester concentrations, with the exception of glycerol, isoamyl acetate and diethyl succinate levels. Remarkably, in wines obtained with mixed cultures the concentration of 2-phenylethyl acetate was approximately 3- to 9-fold greater than that produced by S. cerevisiae pure culture. Moreover sensory evaluation revealed a stronger fruity character in wines fermented with mixed cultures than in control wines. Independently of the mixed culture …
Selection of Debaryomyces hansenii isolates as starters in meat products based on phenotypic virulence factors, tolerance to abiotic stress condition…
2021
Debaryomyces hansenii is a yeast widely used in meat fermentations as starter for the purpose of improving the aromatic quality of the final product. However, it has not been the subject of an extensive study regarding phenotypic characteristics important for starter selection, such as the capacity to grow at abiotic stress conditions occurring during fermentation, the ability to generate desirable aromas and the absence of virulence traits in yeasts.
Price and volatility dynamics between electricity and fuel costs: Some evidence for Spain
2012
Abstract The purpose of this study is to investigate the causal linkages between the Spanish electricity, Brent crude oil and Zeebrugge (Belgium) natural gas 1-month-ahead forward prices. Following Lutkepohl et al. (2004), we control for the presence of a structural change in the series and then we use the Johansen cointegration test and a vector error correction model (VECM) to embrace the analysis. Additionally, a multivariate generalized autoregressive conditional heteroskedastic (GARCH) model is applied to explore volatility interactions between the three markets involved in the study. Our findings reveal that Brent crude oil and Zeebrugge natural gas forward prices play a prominent rol…
Residual-based block bootstrap for cointegration testing
2010
We propose a new testing procedure to determine the rank of cointegration. This new method is based on the nonparametric resampling procedure, so-called Residual-Based Block Bootstrap (RBB), which is developed by Paparoditis and Politis (2003) in the context of unit root testing. Through Monte Carlo experiments we show that, in small samples, the RBB cointegration test has good power properties in relation to the other two well-known tests for cointegration, such as the Augmented Dickey–Fuller (ADF), applied to the residual of a cointegrating regression, and the Johansen's maximum eigenvalue tests. Likewise, this article looks at the influence played by the correlation of the ‘X’ variables …
Influence of indigenous Hanseniaspora uvarum and Saccharomyces cerevisiae from sugar-rich substrates on the aromatic composition of loquat beer
2022
The demand for unique and exclusive food products and beverages is constantly on the increase. One of the products that mostly evolved to encounter market dynamics in the last decade is craft beer. For a long time, craft breweries have included fruit in beer production to enrich flavour and aroma profile of different beer styles. In this study, for the first time, the use of Saccharomyces and non-Saccharomyces yeast strains isolated from high -sugar matrices (manna and fermented honey by-products) were investigated to diversify fruit craft beer pro-duction, in order to improve the fermentation process and highlight the complexity of aroma profiles generated during alcoholic fermentation. Tw…
Enzyme contribution of non-Saccharomyces yeasts to wine production
2015
The fermentation of grape must to produce wine is a biologically complex process, carried on by yeasts and malolactic bacteria. The yeasts present in spontaneous fermentation may be divided into two groups, the Saccharomyces yeasts, particularly S. cerevisiae, and the non-Saccharomyces yeasts which include members of the genera Rhodotorula, Pichia, Candida, Debaryomyces, Metschtnikowia, Hansenula and Hanseniaspora. S. cerevisiae yeasts are able to convert sugar into ethanol and CO2 via fermentation. They have been used for thousands of years by mankind for the production of fermented beverages and foods, including wine. Their enzymes provide interesting wine organoleptic characteristics. β-…