Publications by authors named "Scott Lafontaine"

Understanding the factors which lead to the (in)stability of the chemistry and sensory of hoppy beer styles such as India Pale Ales (IPAs) has become a major concern for many brewers. Therefore, the evolution of several volatiles under different storage conditions (room temperature, cold storage, forced aging) was investigated in eleven hoppy ales and one lager which were commercially produced in Germany. Compared to the lager, the fresh ales contained higher initial aldehyde levels.

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Recently studies based on limited sample sizes procured from minor hop growing regions have speculated that the elemental profile of hops can possibly be used to authenticate the origin of a hop because changes in hop elemental profiles were realted to growing region and that these changes might also be related to beer quality. To explore this further, 205 hop samples (i.e.

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Monoterpenes contribute to the characteristic aroma of several hop varieties and may occur as nonvolatile glycosides. Upon hydrolysis, the volatile terpenes are released from the glycoside precursors. Little is known, however, about the glycoside composition of hops.

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Pentose-hexose monoterpene alcohol glycosides were isolated and semiquantitatively measured in dried cones using UHPLC-qTOF-MS/MS and HPLC fractionation followed by GC-MS. The samples evaluated included hop cones from five important dual-purpose cultivars (varieties) in the United States, from two locations (farms) per variety and from three distinct harvest time points (maturities) per location, as dictated by dry-matter (% w/w) at the time of harvest. Hop variety accounted for the biggest variation among the concentrations of pentose-hexose monoterpene alcohol glycosides as well as other volatile and nonvolatile chemical factors measured in the samples.

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Forty-two commercial non-alcoholic beer (NAB) brands were analyzed using sensory and chemical techniques to understand which analytes and/or flavors were most responsible for invoking the perception of "beer flavor" (for Northern Californian consumers). The aroma and taste profiles of the commercial NABs, a commercial soda, and a carbonated seltzer water (n = 44) were characterized using replicated descriptive and CATA analyses performed by a trained sensory panel (i.e.

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In this study, the chemical and sensory profiles of 42 different nonalcoholic beer (NAB) brands/styles already on the global market and produced through several different brewing techniques were evaluated. A trained panel (i.e.

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The sensorial and chemical differences among Pinot noir wines from different vineyard locations were investigated. Grapes of a single Pinot noir clone were grown on twelve different vineyard sites along the U.S.

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Dysphania is an abundant genus of plants, many of which are endemic to the Australian continent, occurring primarily in arid and temperate zones. Despite their prevalence, very few investigations into the phytochemistry of native Dysphania have been undertaken. Described herein, is the isolation and elucidation of two enantiomeric diastereomers of humulene diepoxide C from D.

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The impact of ripening on the dry-hop aroma potential and chemical development of Cascade hops is not well understood. Therefore, 5-6 weekly hop samples were collected over the 2014, 2015 and 2016 harvests. Concentrations of humulones did not change as a function of harvest date, while total hop essential oil content displayed significant positive trends.

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The range of different nonvolatile constituents extracted from hops in highly hopped beers suggests that isohumulones may not be the sole contributor to beers' bitterness. Among brewers producing hop-forward beer styles, there is concern that the bitterness unit (BU) is no longer an accurate predictor of beer bitterness. This study examined factors within the beer matrix that influence sensory bitterness perception in highly hopped beers.

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The relative influences of trans-Pacific and regional atmospheric transport on measured concentrations of polycyclic aromatic hydrocarbons (PAHs), PAH derivatives (nitro- (NPAH) and oxy-(OPAH)), organic carbon (OC), and particulate matter (PM) less than 2.5 μm in diameter (PM2.5) were investigated in the Pacific Northwest, U.

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