Role of Organic Acids in Maturation of Distilled Spirits in Oak Casks

Maturation of whiskies and brandies in oak casks proceeds by reducing the perception of less desirable aromas of new distillates. During maturation, extraction of wood components increases the solubility of distillate compounds which reduces their headspace concentration above the matured spirit. The origins of this interaction are changes in aggregation of ethanol due to increases in contents of organic acids. During wood maturation organic acid concentrations in spirits increase as a result of extraction from cask wood, oxidation of ethanol and evaporation of ethanol and water. The effect of such changes was simulated using a model whisky ester in aqueous solutions of ethanol with acetic acid, oak wood extracts and acid fractions from new and matured Scotch malt distillates.     

Headspace concentrations of ethyl esters at different alcoholic strengths

Ester concentrations in the headspace influence the aroma character of alcoholic drinks. Activity coefficients for esters showed log-linear decreases as ethanol concentration was increased from 17% (v/v), with rates inversely related to ester acid chain length. At concentrations below 17% (v/v) the activity coefficient remained constant. This could be related to structural changes in ethanol/water mixtures. Below 17% (v/v), ethanol forms a monodispersed aqueous solution. Above 17% (v/v), ethanol molecules cluster to reduce hydrophobic hydration and esters partition into these ethanol-rich clusters, where the lower ester interfacial tension reduces the free energy of mixing and hence the activity coefficient. The increased solubility of the ester reduced the headspace concentration of the esters, and hence total ester content may not be a good indicator of their flavour impact. © 1998 SCI.     

Alcohol and risky sexual behavior: Event-based analyses among a sample of high-risk women.

The effect of alcohol consumption on sexual behavior was examined in a sample of 123 heterosexually active single women who consume alcohol moderately to heavily. Via event-based methodology, women were asked to describe 2 recent sexual encounters with a new or occasional partner, 1 involving alcohol and 1 not involving alcohol. Women were significantly more likely to have sex with a partner they had just met in the encounter involving alcohol than in the encounter not involving alcohol. However, women were no less likely to discuss birth control or AIDS prevention during the alcohol encounter, nor did they perceive less risk of pregnancy, HIV, or sexually transmitted diseases in the alcohol encounter. Although women were more likely to use condoms if they had discussed birth control or HIV prevention, condom use was not affected by alcohol consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Heat Treatments on Steels for Bearing Applications

AISI 52 100, 440C, REX20, and Crucible CRU80 steel samples were exposed to 16 different heat treatments to vary the levels of retained austenite. Rockwell C hardness measurements, optical microscopy, and compression testing were used to compare the properties of the different steels.     

Exploring the loss of semantic memory in semantic dementia: Evidence from a primed monitoring study.

An on-line primed monitoring study was used in an exploration of the nature of semantic memory loss in a patient (P.P.) with semantic dementia who showed a profound semantic impairment on a range of off-line tasks. Priming for pairs of words taken from a common category (e.g., cat-dog, spade-rake, ruby-emerald) was contrasted with that for word pairs from different categories that were related functionally (e.g., shampoo-hair, broom-floor, theater-play). Control participants showed robust priming for both types of semantic relation. P.P., in contrast, showed a normal priming effect for the functionally related conditions but no priming for category coordinates. This result suggests that P.P.'s semantic memory loss cannot be explained solely as a loss of stored representations or as a problem with deliberate controlled access to that information. Rather, elements of both explanations apply for different kinds of semantic information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of women's alcohol consumption in evaluation of vulnerability to sexual aggression.

The authors examined the impact of alcohol consumption on women's risk perceptions and intended behaviors in a hypothetical situation in which the potential for establishing a relationship with an attractive man was coupled with the potential for sexual aggression. Fifty-nine single women, ages 21–29, were randomly assigned to 1 of 3 beverage conditions: (a) alcohol (dose sufficient to raise blood alcohol level to .08); (b) placebo, in which they were led to believe that they had consumed alcohol but had not; or (c) no alcohol, in which they neither expected nor received alcohol. Compared with women in the no–alcohol condition, women in the alcohol condition (a) rated the male character in the vignette more positively, (b) anticipated less risk and more benefit resulting from a series of behaviors likely to facilitate the relationship while increasing sexual vulnerability (e.g., engaging in consensual sexual activities), and (c) anticipated greater involvement in those behaviors. The placebo appeared to exert similar but weaker effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)