The Effect of Sound Frequency and Intensity on Yeast Growth, Fermentation Performance and Volatile Composition of Beer

This study investigated the impact of varying sound conditions (frequency and intensity) on yeast growth, fermentation performance and production of volatile organic compounds (VOCs) in beer. Fermentations were carried out in plastic bags suspended in large water-filled containers fitted with underwater speakers. Ferments were subjected to either 200–800 or 800–2000 Hz at 124 and 140 dB @ 20 µPa. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to identify and measure the relative abundance of the VOCs produced. Sound treatment had significant effects on the number of viable yeast cells in suspension at 10 and 24 h (p < 0.05), with control (silence) samples having the highest cell numbers. For wort gravity, there were significant differences between treatments at 24 and 48 h, with the silence control showing the lowest density before all ferments converged to the same final gravity at 140 h. A total of 33 VOCs were identified in the beer samples, including twelve esters, nine alcohols, three acids, three aldehydes, and six hop-derived compounds. Only the abundance of some alcohols showed any consistent response to the sound treatments. These results show that the application of audible sound via underwater transmission to a beer fermentation elicited limited changes to wort gravity and VOCs during fermentation.

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Health Risk Assessment of Toxic and Harmful Air Pollutants Discharged by a Petrochemical Company in the Beijing-Tianjin-Hebei Region of China

Atmosphere ◽

10.3390/atmos12121604 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1604

Author(s):

Tao Zhu ◽

Furong Li ◽

Wenfeng Niu ◽

Zijun Gao ◽

Yiwei Han ◽

...

Keyword(s):

Air Pollutants ◽

Solid Phase ◽

Carcinogenic Risk ◽

Pollutant Emissions ◽

Oil Refining ◽

Pollutant Emission ◽

Gas Chromatography Mass Spectrometry ◽

Hazardous Air Pollutants ◽

Petrochemical Company ◽

The Impact

Monitoring of toxic and hazardous air pollutants (HAPs) in a petrochemical company in the Beijing-Tianjin-Hebei region of China to assess the impact of HAPs on the health risks of workers in the petrochemical company. The samples were tested by solid-phase adsorption thermal desorption/gas chromatography-mass spectrometry (HJ734-2014), and the pollutant emission list was obtained. According to the pollutant emission inventory, it can be seen that benzene, toluene and xylene are the main components of toxic and harmful air pollutants emitted by the petrochemical enterprise. The method of combining actual monitoring and CALPUFF model prediction was used to evaluate the impact of the toxic and harmful air pollutants emitted by the enterprise on the health of workers. The risk characterization results show that when benzene is the maximum concentration value predicted by the model, it will pose a carcinogenic risk to the factory workers. Therefore, based on the results of this study, it is recommended not to allow residents to live within the predicted concentration range of the model. The results of this study can enable China’s oil refining industry to better understand the characteristics of pollutant emissions from petrochemical companies in the Beijing-Tianjin-Hebei region. Moreover, the results of this study can be used as a policy basis for improving the health of workers in petrochemical enterprises, and are of great significance to the protection of public health.

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Madeira Wine Volatile Profile. A Platform to Establish Madeira Wine Aroma Descriptors

Molecules ◽

10.3390/molecules24173028 ◽

2019 ◽

Vol 24 (17) ◽

pp. 3028 ◽

Cited By ~ 5

Author(s):

Rosa Perestrelo ◽

Catarina Silva ◽

José S. Câmara

Keyword(s):

Solid Phase ◽

Point Of View ◽

Gas Chromatography Mass Spectrometry ◽

Wine Aroma ◽

Grape Variety ◽

Volatile Phenols ◽

Starting Point ◽

Furanic Compounds ◽

The Impact ◽

And Diffusion

In the present study we aimed to investigate the volatile organic compounds (VOCs) that may potentially be responsible for specific descriptors of Madeira wine providing details about Madeira wine aroma notes at molecular level. Moreover, the wine aroma profile, based on the obtained data, will be a starting point to evaluate the impact of grape variety (Malvasia, Bual, Sercial, Verdelho and Tinta Negra), type (sweet, medium sweet, dry and medium dry), and age (from 3 to 20 years old) on Madeira wine sensorial properties. Firstly, a comprehensive and in-depth Madeira wine volatile profiling was carried out using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS–SPME/GC–qMS). Secondly, a relation among the varietal, fermentative and aging aroma compounds, and their aroma descriptors with the Madeira wine sensorial properties was assessed. A total of 82 VOCs, belonging to different chemical families were identified, namely 21 esters, 13 higher alcohols, ten terpenic compounds, nine fatty acids, seven furanic compounds, seven norisoprenoids, six lactones, four acetals, four volatile phenols and one sulphur compound. From a sensorial point of view, during the aging process the wine lost its freshness and fruitiness odor related to the presence of some varietal and fermentative compounds, whereas other descriptors such as caramel, dried fruits, spicy, toasty and woody, arose during ageing. The Maillard reaction and diffusion from the oak were the most important pathways related with these descriptors. A relationship-based approach was used to explore the impact of grape variety, wine type, and age on Madeira wine sensorial properties based on shared number of VOCs and their odors.

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Contribution of Grape Skins and Yeast Choice on the Aroma Profiles of Wines Produced from Pinot Noir and Synthetic Grape Musts

Fermentation ◽

10.3390/fermentation7030168 ◽

2021 ◽

Vol 7 (3) ◽

pp. 168

Author(s):

Yifeng Qiao ◽

Diana Hawkins ◽

Katie Parish-Virtue ◽

Bruno Fedrizzi ◽

Sarah J. Knight ◽

...

Keyword(s):

Solid Phase Microextraction ◽

Solid Phase ◽

Fermentation Medium ◽

Pinot Noir ◽

Gas Chromatography Mass Spectrometry ◽

Wine Quality ◽

Aroma Profile ◽

Aroma Production ◽

Grape Skins ◽

The Impact

The aroma profile is a key component of Pinot noir wine quality, and this is influenced by the diversity, quantity, and typicity of volatile compounds present. Volatile concentrations are largely determined by the grape itself and by microbial communities that produce volatiles during fermentation, either from grape-derived precursors or as byproducts of secondary metabolism. The relative degree of aroma production from grape skins compared to the juice itself, and the impact on different yeasts on this production, has not been investigated for Pinot noir. The influence of fermentation media (Pinot noir juice or synthetic grape must (SGM), with and without inclusion of grape skins) and yeast choice (commercial Saccharomyces cerevisiae EC1118, a single vineyard mixed community (MSPC), or uninoculated) on aroma chemistry was determined by measuring 39 volatiles in finished wines using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC-MS). Fermentation medium clearly differentiated the volatile profile of wines with and without yeast, while differences between EC1118 and MSPC wines were only distinct for Pinot noir juice without skins. SGM with skins produced a similar aroma profile to Pinot noir with skins, suggesting that grape skins, and not the pulp, largely determine the aroma of Pinot noir wines.

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Preanalytical Variables Affecting the Quantification of Fatty Acid Ethyl Esters in Plasma and Serum Samples

Clinical Chemistry ◽

10.1093/clinchem/45.12.2183 ◽

1999 ◽

Vol 45 (12) ◽

pp. 2183-2190 ◽

Cited By ~ 30

Author(s):

Britt L Soderberg ◽

Ewa T Sicinska ◽

Emily Blodget ◽

Joanne E Cluette-Brown ◽

Paolo M Suter ◽

...

Keyword(s):

Fatty Acid ◽

Solid Phase ◽

Alcoholic Beverage ◽

Ethanol Consumption ◽

Ethanol Intake ◽

Fatty Acid Ethyl Esters ◽

Ethyl Esters ◽

Gas Chromatography Mass Spectrometry ◽

Clinical Test ◽

The Impact

Abstract Background: Fatty acid ethyl esters (FAEEs) are cytotoxic nonoxidative ethanol metabolites produced by esterification of fatty acids and ethanol. FAEEs are detectable in blood up to 24 h after ethanol consumption. The objective of this study was to assess the impact of gender, serum or plasma triglyceride concentration, time and temperature of specimen storage, type of alcoholic beverage ingested, and the rate of ethanol consumption on FAEE concentrations in plasma or serum. Methods: For some studies, subject were recruited volunteers; in others, residual blood samples after ethanol quantification were used. FAEEs were isolated by solid-phase extraction and quantified by gas chromatography–mass spectrometry. Results: For weight-adjusted amounts of ethanol intake, FAEE concentrations were twofold greater for men than women (P ≤0.05). Accounting for triglycerides improved the correlation between blood ethanol concentrations and FAEE concentrations for both men (from r = 0.640 to r = 0.874) and women (from r = 0.619 to r = 0.673). FAEE concentrations did not change when samples were stored at or below 4 °C, but doubled when stored at room temperature for ≥24 h. The type of alcoholic beverage and rate of consumption did not affect FAEE concentrations. Conclusion: These studies advance plasma and serum FAEE measurements closer to implementation as a clinical test for ethanol intake.

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The Impact of Optical Berry Sorting on Red Wine Composition and Sensory Properties

Foods ◽

10.3390/foods10020402 ◽

2021 ◽

Vol 10 (2) ◽

pp. 402

Author(s):

Robert C. Bruce ◽

Pauline Lestringant ◽

Charles A. Brenneman ◽

Hildegarde Heymann ◽

Anita Oberholster

Keyword(s):

Solid Phase ◽

Reversed Phase ◽

Sensory Properties ◽

Gas Chromatography Mass Spectrometry ◽

Cabernet Sauvignon ◽

Minimal Impact ◽

Color Parameters ◽

Optical Sorting ◽

And Control ◽

The Impact

The impact of optical berry sorting was investigated using Grenache, Barbera, and Cabernet Sauvignon grapes from Yolo County, California in 2016. Optical sorting parameters were adjusted to remove underripe berries and material other than grapes using color parameters. Wines were made from three treatments, control (no sorting), sort (accepted material), and reject (material rejected by the optical sorter). The rate of rejection was approximately 14.9%, 3.9%, and 1.5% (w/w) for Grenache, Barbera, and Cabernet Sauvignon, respectively. Chemical composition in the finished wines was analyzed by the Adams-Harbertson assay and reversed-phase high-performance liquid chromatography for phenolics, and head-space solid-phase microextraction gas chromatography mass spectrometry for aroma profiling. In general, optical sorting was successful in removing underripe berries and material other than grapes as evidenced by lower ethanol levels and higher concentrations of total phenolics and tannin (due to the inclusion of material other than grapes) in wine made from rejected material. Despite this, no difference in final ethanol content and minimal differences in phenolic composition were observed between control and sort treatment wines for the three varieties studied. Differences were observed in the aroma profiles of the reject treatments for all three varieties compared to sort and control; however, few compounds differed significantly between the sort and control treatments. Descriptive sensory analysis revealed that panelists had difficulty distinguishing aroma, taste, mouthfeel, and color parameters among wines made from different treatments for all three varieties. Thus, optical sorting had minimal impact on wine sensory properties using the varieties and vineyards studied. Optical sorting may be used to differentiate and sort for different ripeness levels using color as a primary criterion; however, the impact on the resulting wine is likely dependent on the initial variability in grape ripeness.

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Oenological Characteristics of Fermented Apple Musts and Volatile Profile of Brandies Obtained from Different Apple Cultivars

Biomolecules ◽

10.3390/biom10060853 ◽

2020 ◽

Vol 10 (6) ◽

pp. 853 ◽

Cited By ~ 1

Author(s):

Magdalena Januszek ◽

Paweł Satora ◽

Tomasz Tarko

Keyword(s):

Gas Chromatography ◽

Volatile Compounds ◽

Solid Phase ◽

Alcoholic Beverages ◽

Gas Chromatography Mass Spectrometry ◽

Volatile Profile ◽

Flame Ionization ◽

Isopropyl Acetate ◽

Apple Cultivars ◽

The Impact

Volatile profile of spirits is the most important factor, because it can contribute to pleasant flavor. The aim of the study was to determine the impact of dessert apple cultivar used for fermentation on the concentration of volatile compounds in apple spirits. SPME-GC-MS (solid-phase microextraction- gas chromatography- mass spectrometry) method enables the detection of 69 substances and GC-FID (gas chromatography - flame ionization detector) 31 compounds. Characteristic volatiles for brandies obtained from Topaz were limonene, myrcene, methyl valerate and 1,1-diethoxy-propane, from Rubin—β-citronellol and isopropyl acetate, Elise—limonene, myrcene benzyl acetate and isopropyl acetate, Szampion—β-citronellol, Idared—1,1-diethoxy-propane and Jonagored—ethyl trans-4-decanoate. Of the ten analyzed apple spirits, those obtained from Topaz, Rubin and Elise cultivars demonstrated the most diverse profile of volatile compounds. Moreover, their oenological parameters that are the most important in the production of alcoholic beverages were the most favorable. On the other hand, the content of sugars was relatively low in Elise must, while it was highest in Topaz must, which later on translated into differences in alcohol content. Brandies obtained from Gloster contained the smallest concentrations of esters and terpenes. Results of the sensory analysis showed that highest rated brandies were obtained from Topaz, Rubin, Elise and Florina.

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SPME Method Optimized by Box-Behnken Design for Impact Odorants in Reduced Alcohol Wines

10.20944/preprints201807.0394.v1 ◽

2018 ◽

Author(s):

Bithika Saha ◽

Rocco Longo ◽

Peter Torley ◽

Anthony Saliba ◽

Leigh Schmidtke

Keyword(s):

Ethanol Concentration ◽

Solid Phase ◽

Desirability Function ◽

Accurate Determination ◽

Gas Chromatography Mass Spectrometry ◽

Extraction Temperature ◽

Volatile Composition ◽

Ethanol Content ◽

The Impact ◽

Three Factor

The important sampling parameters of a headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure, extraction temperature, extraction time and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken experiments was used to determine optimized sampling conditions for each analyte, and a global optimized condition at every ethanol concentration of interest determined using a desirability function that accounts for a low signal response for compounds. Shiraz and Chardonnay wines were dealcoholized from 13.7 and 12.2% v/v ethanol respectively, to 8 and 5% v/v, using a commercially available membrane-based technology. A sample set of the reduced alcohol wines were also reconstituted to their natural ethanol level to evaluate the effect of ethanol content reduction on volatile composition. The three-factor Box-Behnken experiment ensured an accurate determination of the headspace concentration of each compound at each ethanol concentration, allowing comparisons between wines at varying ethanol levels to be made. Overall, the results showed that the main effect of extraction temperature was considered the most critical factor when studying the equilibrium of reduced alcohol wine impact odorants. The impact of ethanol reduction upon the concentration of volatile compounds clearly resulted in losses of impact odorants from the wines. The concentration of most analytes decreased with dealcoholization compared to that of the natural samples. Significant differences were also found between the reconstituted volatile composition and 5% v/v reduced alcohol wines, revealing that the dealcoholization effect is the result of a combination between the type of dealcoholization treatment and reduction in wine ethanol content.

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The Effects of Storage Temperature on the Aroma of Whole Bean Arabica Coffee Evaluated by Coffee Consumers and HS-SPME-GC-MS

Beverages ◽

10.3390/beverages4030068 ◽

2018 ◽

Vol 4 (3) ◽

pp. 68 ◽

Cited By ~ 2

Author(s):

Andrew Cotter ◽

Helene Hopfer

Keyword(s):

Room Temperature ◽

Storage Temperature ◽

Solid Phase ◽

Storage Conditions ◽

Gas Chromatography Mass Spectrometry ◽

Green Beans ◽

Projective Mapping ◽

Shelf Stable ◽

Product Maps ◽

The Impact

Although from a food safety point, coffee is considered a shelf-stable product, changes in volatiles over time due to out-gassing and chemical reactions lead to perceivable differences in coffee aroma and “freshness”. Previous studies have looked at the impact of storage conditions on ground or brewed coffee. This study seeks to answer the question of how coffee consumers perceive the smell of coffee grounds of whole beans that have been stored under different conditions: freezer vs. room temperature for 9 weeks compared to a newly roasted control (stored for 1 day). Green beans from the same production lot were roasted to two different levels to also evaluate the impact of roast level on aroma changes. Using projective mapping (PM) followed by ultra-flash profiling (UFP), 48 coffee consumers evaluated, using only smell, 6 different freshly ground coffee samples presented in blind duplicates. In parallel, the profiles of 48 previously reported important coffee volatiles were measured by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) to relate chemical changes to perceivable sensory aroma changes. Overall, consumer product maps mimicked the instrumental measurements in that the lighter roast coffees showed smaller changes due to storage conditions compared to the dark roast samples. Consumers also perceived the frozen dark roast samples to be more similar to the newly roasted control than the samples stored at room temperature.

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Volatile Compounds Emitted from the Cat Urine Contaminated Carpet before and after Treatment with Marketed Cleaning Products: A Simultaneous Chemical and Sensory Analysis

Data ◽

10.3390/data5040088 ◽

2020 ◽

Vol 5 (4) ◽

pp. 88

Author(s):

Chumki Banik ◽

Jacek A. Koziel ◽

Elizabeth Flickinger

Keyword(s):

Solid Phase ◽

Micrococcus Luteus ◽

Gas Chromatography Mass Spectrometry ◽

Household Dust ◽

Water Control ◽

Cleaning Product ◽

Cleaning Products ◽

Before And After ◽

The Impact ◽

Over Time

Urination on carpet and subflooring can develop into a persistent and challenging problem when trying to mitigate odor. Very little or no information is published on how volatile organic compounds (VOCs) change over time when urine is deposited on a carpet covering a plywood-type subflooring. This research has investigated the VOCs emitted from carpet + subflooring (control), carpet + subflooring sprayed with water (control with moisture), and cat urine-contaminated carpet + subflooring (treatment) over time (day 0 and 15). In addition, the study has recorded the effect of four popular cleaning product applications on VOCs emitted from carpet and evaluated their efficacy in eliminating cat urine related indoor odors over time (days 0 and 15). Carpet-subflooring with all treatments were also contaminated with Micrococcus luteus, a nonmotile obligate aerobe commonly found in household dust, to observe the impact of the aerobe on carpet-subflooring VOCs emission. VOCs emitted from carpet + subflooring receiving different treatments were collected from headspace using solid-phase microextraction (SPME). The VOCs were analyzed using a gas chromatography-mass spectrometry olfactometry (GC-MS-O). Many common VOCs were released from the carpet on day 0 and day 15, specifically from urine contamination. Cleaning products were effective in masking several potent odors of cat urine contaminated carpet VOCs on day 0 but were unable to remove the odor that appeared on day 15 in most cases.

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SPME Method Optimized by Box-Behnken Design for Impact Odorants in Reduced Alcohol Wines

Foods ◽

10.3390/foods7080127 ◽

2018 ◽

Vol 7 (8) ◽

pp. 127 ◽

Cited By ~ 5

Author(s):

Bithika Saha ◽

Rocco Longo ◽

Peter Torley ◽

Anthony Saliba ◽

Leigh Schmidtke

Keyword(s):

Ethanol Concentration ◽

Solid Phase ◽

Desirability Function ◽

Accurate Determination ◽

Gas Chromatography Mass Spectrometry ◽

Extraction Temperature ◽

Volatile Composition ◽

Ethanol Content ◽

The Impact ◽

Three Factor

The important sampling parameters of a headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure such as the extraction temperature, extraction time, and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken experiments was used to determine the optimized sampling conditions for each analyte, and a global optimized condition at every ethanol concentration of interest determined using a desirability function that accounts for a low signal response for compounds. Shiraz and Chardonnay wines were dealcoholized from 13.7 and 12.2% v/v ethanol respectively, to 8 and 5% v/v, using a commercially available membrane-based technology. A sample set of the reduced alcohol wines were also reconstituted to their natural ethanol level to evaluate the effect of the ethanol content reduction on volatile composition. The three-factor Box-Behnken experiment ensured an accurate determination of the headspace concentration of each compound at each ethanol concentration, allowing comparisons between wines at varying ethanol levels to be made. Overall, the results showed that the main effect of extraction temperature was considered the most critical factor when studying the equilibrium of reduced alcohol wine impact odorants. The impact of ethanol reduction upon the concentration of volatile compounds clearly resulted in losses of impact odorants from the wines. The concentration of most analytes decreased with dealcoholization compared to that of the natural samples. Significant differences were also found between the reconstituted volatile composition and 5% v/v reduced alcohol wines, revealing that the dealcoholization effect is the result of a combination between the type of dealcoholization treatment and reduction in wine ethanol content.

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