Effects of distillation cut on the distribution of higher alcohols and esters in brandy produced from three plum varieties

The purpose of this investigation was to determinate effects of distillation cuts on the distributions of higher alcohols (1‐propanol, 2‐methyl‐1‐propanol, 3‐methyl‐1‐butanol, 2‐methyl‐1‐butanol, 1‐butanol, 2‐butanol, 1‐hexanol and 1‐pentanol) and esters (ethyl acetate, isopentyl acetate + ethyl lactate, isobutyl acetate, ethyl propionate and ethyl butyrate) in plum brandy. The volatiles were determined by gas chromatography–flame ionization detection. The three most popular plum varieties used in plum brandy (Sljivovica) production, Stanley, Pozegaca and Bilska rana (Buhler), were distilled using a traditional distilling pot and fraction distillation. Three distillation cuts were considered. After separating the head fraction, in the amount of 1.7% of the distilling pot volume, heart fractions were cut at 40, 45 and 50% (v/v) ethanol and tail fractions, analogous to the heart fraction, were collected up to 10% (v/v) ethanol. The ratio of the content of 2‐methyl‐1‐propanol and 3‐methyl‐1‐butanol was 1:1 in the plum brandy produced from Stanley and Pozegaca and the ratio was 2:1 in the plum brandy produced from Bilska rana. This ratio can be used as a ‘mark’ of variety recognition in plum brandy production. The main differences in the heart fraction were accounted for by the content of the higher alcohols and esters for the distilling cut at 40 and 50% (v/v) ethanol. Copyright © 2013 The Institute of Brewing & Distilling.     

Aroma compounds in barrel aged apple distillates from two different distillation techniques

The major fermentation and maturation related congeners in apple distillates from two different distillation techniques (alembic and column), matured in oak for 18 months, were measured by GC‐MS and HPLC. Together with a higher ethanol content, column distillates had higher ethyl acetate, methanol and n‐propanol levels compared with alembic distillates. A higher content of acetaldehyde was characteristic of the alembic distillates. The concentrations of i‐butanol, n‐butanol, amyl alcohols and n‐hexanol were not affected by the distillation technique used. Increasing the ageing time of distillates in oak resulted in an increase in the contents of acetaldehyde, ethyl acetate and amyl alcohols while the content of methanol decreased during ageing. Throughout ageing, there were no significant changes in the concentrations of n‐propanol, i‐butanol, n‐butanol and n‐hexanol. Among the maturation related compounds, gallic acid, ellagic acid, vanillin and syringaldehyde were determined in apple distillates with ellagic acid being the most abundant. The contents of gallic acid and ellagic acid increased during ageing whereas vanillin and syringaldehyde slightly increased throughout the 18 months of maturation. © 2019 The Institute of Brewing & Distilling     

Controlled Release of LL‐37‐Derived Synthetic Antimicrobial and Anti‐Biofilm Peptides SAAP‐145 and SAAP‐276 Prevents Experimental Biomaterial‐Associated Staphylococcus aureus Infection

The present study aims to develop an implant coating releasing novel antimicrobial agents to prevent biomaterial‐associated infections. The LL‐37‐derived synthetic antimicrobial and anti‐biofilm peptides (SAAP)‐145 and SAAP‐276 exhibit potent bactericidal and anti‐biofilm activities against clinical and multidrug‐resistant Staphylococcus aureus strains by rapid membrane permeabilization, without inducing resistance. Injection of SAAP‐145, but not SAAP‐276, along subcutaneous implants in mice reduces S. aureus implant colonization by approximately 2 log, but does not reduce bacterial numbers in surrounding tissue. To improve their efficacy, SAAP‐145 and SAAP‐276 are incorporated in a polymer–lipid encapsulation matrix (PLEX) coating, providing a constant release of 0.6% daily up to 30 d after an initial burst release of >50%. In a murine model for biomaterial‐associated infection, SAAP‐145‐PLEX and SAAP‐276‐PLEX coatings significantly reduce the number of culture positive implants and show ≥3.5 and ≥1.5 log lower S. aureus implant and tissue colonization, respectively. Interestingly, these peptide coatings are also highly effective against multidrug‐resistant S. aureus, both reducing implant colonization by ≥2 log. SAAP‐276‐PLEX additionally reduces tissue colonization by 1 log. Together, the peptide‐releasing PLEX coatings hold promise for further development as an alternative to coatings releasing conventional antibiotics to prevent biomaterial‐associated infections.