Tobacco users are much more susceptible to dental caries and periodontal diseases than non-tobacco users. Research suggests that this increased susceptibility may be due in part to nicotine, a primary active component of tobacco. Five bacterial species and one yeast species commonly found in the human oral cavity, Lactobacillus casei, Actinomyces viscosus, Actinomyces naeslundii, Rothia dentocariosa, Enterococcus faecalis, and Candida albicans respectively, were utilized to investigate if any correlation existed between exposure to various concentrations of nicotine ranging from 0 to 32 mg/ml and the growth of each microorganism. The minimum inhibitory concentration (MIC), minimum biofilm inhibitory concentration (MBIC), and planktonic growth were measured. The MIC was determined to be 16 mg/ml for all organisms except E. faecalis, which had an MIC of 32 mg/ml. Nicotine had a varying effect on planktonic growth across the different species. A distinct upward trend in biofilm formation was found in A. viscosus, L. casei, E. faecalis, and C. albicans through 8 mg/ml. Nicotine also enhanced R. dentocariosa biofilm formation in all concentrations through 8 mg/ml but was most enhanced at 1 mg/ml. Alternatively, A. naeslundii exhibited a complete downward trend through 32 mg/ml. The MBIC was found to be 16 mg/ml in all organisms studied. These findings further support research suggesting that the increased susceptibility to oral health diseases experienced by tobacco users may be caused in part by an upregulation in biofilm formation of these oral pathogens.

Cis-Rose oxide was found to be an important chiral compound in Gewürztraminer wine, with an enantiomeric ratio range from 76 to 58%. The enantiomeric ratio showed an important influence on white wine aroma when other monoterpenes were present. The aim of this study was to evaluate rose oxide at different ratios and changes to aroma perception, and the interaction of rose oxide with linalool and α-terpineol. A wine model was made based on Gewürztraminer wine. Twelve models were created with different ratios of rose oxide and concentrations of linalool and α-terpineol. Triangle tests, check-all-that-apply (CATA) and descriptive analysis were used to evaluate the aroma of the wines. Results show that the rose oxide ratios of 70:30 and 65:35 were statistically different. Additional descriptive analysis showed that the ratios altered aroma when linalool and α-terpineol were at low and medium concentrations. At high concentrations, linalool and α-terpineol masked any influence from rose oxide. Understanding how monoterpenes alter aroma perception of white wine when at different combinations and concentrations is important to achieving desired wine qualities and helps provide information on how flavor chemistry results can be interpreted without having to run sensory analysis.

Lipids have important impacts on wine sensory. By targeting the lipid sources in wine, mainly from grape tissues and yeast cell walls, it was possible to alter the wine lipid profile thus potentially changing the final product quality. This research examined the changes of wine total lipids, lipid composition and sensory characteristics of Pinot noir wines in response to the winemaking factors, fermentation temperature and yeast product addition. Pinot noir grapes were fermented at 16 °C and 27 °C. After fermentation, Oenolees® yeast product was added to the wines at three levels (0 g/L, 0.5 g/L and 1.0 g/L). The six wine treatments were subjected to chemical analyses measuring total lipids and an untargeted lipidomic approach analyzing lipid composition. High temperature fermentation wines had significantly higher total lipid content. Random forest analysis distinguished the wine groups based on the 25 main lipids, including free fatty acids, acylcarnitines, diglycerides, triglycerides and phospholipids. Taste and mouthfeel characteristics of each treatment were assessed using descriptive analysis and check-all-that-apply (CATA) techniques. Multivariate analyses showed that changing fermentation temperature significantly impacted sweetness and drying perception in Pinot noir wines. Yeast product addition had nuanced effects on wine lipid profiles and sensory perception.

Background and Aims: This study compared changes in the concentration of ρ-coumaric acid in wine because of enzymatic hydrolysis of ρ-coutaric acid by Oenocococcus oeni with that of chemical hydrolysis during ageing. Methods and Results: Malolactic fermentation of a Pinot Noir wine with a cinnamoyl esterase-positive (CE+) O. oeni strain resulted in a significant increase in ρ-coumaric acid concentration. No significant change in ρ-coumaric acid concentration occurred during ageing regardless of wine pH, ethanol concentration or storage temperature. Brettanomyces bruxellensis produced a significantly higher concentration of volatile phenols in wines that underwent malolactic fermentation with the CE (+) O. oeni strain than with the CE (−) strain. Conclusions: The O. oeni strain had significantly more impact on wine ρ-coumaric acid concentration than chemical hydrolysis during ageing. Significance of the Study: The use of CE (+) O. oeni strains should be avoided in wines at risk of Brettanomyces spoilage because of an increase in the concentration of the volatile phenol precursor, ρ-coumaric acid.

An “omics”-style approach was used to evaluate the complex relationship between whisky aroma and dilution with water, typically suggested as a way to better appreciate whisky. A set of 25 samples, including Bourbons, ryes, single-malt and blended Scotches, and Irish whiskies were chemically profiled at six dilution levels (100, 90, 80, 70, 60, and 50% whisky/water), while a subset of six whiskies (three Bourbons, three Scotches) at four dilution levels (100, 80, 60, and 40% whisky/water) were chemically profiled and subjected to sensory analysis by a trained panel (n = 20). Untargeted volatile analysis was performed using headspace solid-phase microextraction gas chromatography coupled with mass spectrometry (HS-SPME-GC-MS) and sensory analysis was performed using descriptive analysis (DA). Results were evaluated using multivariate statistical techniques, including multifactor analysis (MFA) and partial least squares discriminant analysis (PLS-DA). Dilution decreased headspace concentration of hydrophilic aroma compounds and increased concentration of more hydrophobic compounds, which agreed with DA results. Dilution above 80% whisky/20% water reduced differences within whisky styles, though differences between American (Bourbon, rye) and Scotch styles (single malt, blended) continued to increase with further dilution. This provides important insight into how dilution of whisky during consumption changes consumer perception, as well as the usefulness of HS-SPME-GC-MS as a proxy for human olfaction.