scholarly journals Ethyl 2-hydroxy-3-methylbutanoate enantiomers: quantitation and sensory evaluation in wine

OENO One ◽  
2018 ◽  
Vol 52 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Marine Gammacurta ◽  
Sophie Tempere ◽  
Stéphanie Marchand ◽  
Virginie Moine ◽  
Gilles De Revel
Keyword(s):  
Red Wine ◽  
Detection Threshold ◽  
Sensory Characteristics ◽  
Detection Thresholds ◽  
White Wines ◽  
Enantiomeric Ratio ◽  
Potential Marker ◽  
Significant Difference ◽  
Sensory Tests ◽  
Chiral Gas Chromatography

Aim: To investigate chemical and sensory characteristics of ethyl 2-hydroxy-3-methylbutanoate in wines.Methods and results: Ethyl 2-hydroxy-3-methylbutanoate has been recently identified as a potential marker of lactic acid bacteria esterase activity. Enantiomers of this fruity ester were quantitated in 99 wines from various vintages and French regions using chiral gas chromatography (γ-cyclodextrin phase). Analyses revealed the predominant presence of the R enantiomer in red and white wines, with a maximum R/S enantiomeric ratio of 94/6 in a 1993 red wine. Results also highlighted greater levels of the ester in red than white wines, depending on grape origin. The detection thresholds of the R- and S-form were estimated at 4 µg/L and 1.5 µg/L in water and 51 mg/L and 21 mg/L in red wine, respectively. Moreover, ranking tests made with levels found in wines did not show significant sensory differences.Conclusion: The concentrations found in wines were considerably below the detection threshold, indicating no direct effect of these compounds on fruity aroma modulation. The absence of significant difference in sensory tests demonstrates that ethyl 2-hydroxy-3-methylbutanoate does not contribute significantly to the fruity aroma of red wine.Significance and impact of the study: To our knowledge, no previous research had determined the enantiomeric distribution and the sensory characteristics of this compound in wine.

scholarly journals Is Peripheral Motion Detection Affected by Myopia?

2021 ◽  
Vol 15 ◽  
Author(s):  
Junhan Wei ◽  
Deying Kong ◽  
Xi Yu ◽  
Lili Wei ◽  
Yue Xiong ◽  
...  
Keyword(s):  
Visual Field ◽  
Spatial Frequency ◽  
Motion Detection ◽  
High Speed ◽  
Detection Threshold ◽  
High Spatial Frequency ◽  
Spherical Equivalent ◽  
Detection Thresholds ◽  
Significant Difference ◽  
Motion Speed

PurposeThe current study was to investigate whether myopia affected peripheral motion detection and whether the potential effect interacted with spatial frequency, motion speed, or eccentricity.MethodsSeventeen young adults aged 22–26 years participated in the study. They were six low to medium myopes [spherical equivalent refractions −1.0 to −5.0 D (diopter)], five high myopes (<-5.5 D) and six emmetropes (+0.5 to −0.5 D). All myopes were corrected by self-prepared, habitual soft contact lenses. A four-alternative forced-choice task in which the subject was to determine the location of the phase-shifting Gabor from the four quadrants (superior, inferior, nasal, and temporal) of the visual field, was employed. The experiment was blocked by eccentricity (20° and 27°), spatial frequency (0.6, 1.2, 2.4, and 4.0 cycles per degree (c/d) for 20° eccentricity, and 0.6, 1.2, 2.0, and 3.2 c/d for 27° eccentricity), as well as the motion speed [2 and 6 degree per second (d/s)].ResultsMixed-model analysis of variances showed no significant difference in the thresholds of peripheral motion detection between three refractive groups at either 20° (F[2,14] = 0.145, p = 0.866) or 27° (F[2,14] = 0.475, p = 0.632). At 20°, lower motion detection thresholds were associated with higher myopia (p < 0.05) mostly for low spatial frequency and high-speed targets in the nasal and superior quadrants, and for high spatial frequency and high-speed targets in the temporal quadrant in myopic viewers. Whereas at 27°, no significant correlation was found between the spherical equivalent and the peripheral motion detection threshold under all conditions (all p > 0.1). Spatial frequency, speed, and quadrant of the visual field all showed significant effect on the peripheral motion detection threshold.ConclusionThere was no significant difference between the three refractive groups in peripheral motion detection. However, lower motion detection thresholds were associated with higher myopia, mostly for low spatial frequency targets, at 20° in myopic viewers.

scholarly journals Characterisation of Extracts Obtained from Unripe Grapes and Evaluation of Their Potential Protective Effects against Oxidation of Wine Colour in Comparison with Different Oenological Products

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1499
Author(s):  
Giovanna Fia ◽  
Ginevra Bucalossi ◽  
Bruno Zanoni
Keyword(s):  
Antioxidant Activity ◽  
Red Wine ◽  
Waste Product ◽  
Natural Antioxidants ◽  
White Wine ◽  
Small Scale ◽  
Protective Effects ◽  
White Wines ◽  
Accelerated Oxidation ◽  
Wine Colour

Unripe grapes (UGs) are a waste product of vine cultivation rich in natural antioxidants. These antioxidants could be used in winemaking as alternatives to SO2. Three extracts were obtained by maceration from Viognier, Merlot and Sangiovese UGs. The composition and antioxidant activity of the UG extracts were studied in model solutions at different pH levels. The capacity of the UG extracts to protect wine colour was evaluated in accelerated oxidation tests and small-scale trials on both red and white wines during ageing in comparison with sulphur dioxide, ascorbic acid and commercial tannins. The Viognier and Merlot extracts were rich in phenolic acids while the Sangiovese extract was rich in flavonoids. The antioxidant activity of the extracts and commercial tannins was influenced by the pH. In the oxidation tests, the extracts and commercial products showed different wine colour protection capacities in function of the type of wine. During ageing, the white wine with the added Viognier UG extract showed the lowest level of colour oxidation. The colour of the red wine with the UG extract evolved similarly to wine with SO2 and commercial tannins. The obtained results indicated that natural and healthy UG extracts could be an interesting substitute for SO2 during wine ageing.

scholarly journals Effect of enological treatments on phenolic and sensory characteristics of red wine during aging: Micro-oxygenation, sulfur dioxide, iron with copper and gelatin fining

2021 ◽  
Vol 339 ◽  
pp. 127848
Author(s):  
Natka Ćurko ◽  
Karin Kovačević Ganić ◽  
Marina Tomašević ◽  
Leo Gracin ◽  
Michael Jourdes ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Red Wine ◽  
Sensory Characteristics

Effect of Realistic Test Conditions on Spectral and Temporal Processing in Normal-Hearing Listeners

2021 ◽  
Vol 30 (1) ◽  
pp. 160-169
Author(s):  
Yang-Soo Yoon ◽  
Callie Michelle Boren ◽  
Brianna Diaz
Keyword(s):  
Temporal Processing ◽  
Detection Threshold ◽  
Frequency Discrimination ◽  
Normal Hearing ◽  
Discrimination Threshold ◽  
Test Environment ◽  
Test Conditions ◽  
Significant Difference ◽  
Test Order ◽  
Pure Tones

Purpose To measure the effect of testing conditions (in the soundproof booth vs. quiet room), test order, and number of test sessions on spectral and temporal processing in normal-hearing (NH) listeners. Method Thirty-two adult NH listeners participated in the three experiments. For all three experiments, the stimuli were presented to the left ear at the subjects' most comfortable level through headphones. All tests were administered in an adaptive three-alternative forced-choice paradigm. Experiment 1 was designed to compare the effect of soundproof booth and quiet room test conditions on amplitude modulation detection threshold and modulation frequency discrimination threshold with each of the five modulation frequencies. Experiment 2 was designed to compare the effect of two test orders on the frequency discrimination thresholds under the quiet room test conditions. The thresholds were first measured in the ascending and descending order of four pure tones, and then with counterbalanced order. For Experiment 3, the amplitude discrimination threshold under the quiet room testing condition was assessed 3 times to determine the effect of the number of test sessions. Then the thresholds were compared over the sessions. Results Results showed no significant effect of test environment. The test order is an important variable for frequency discrimination, particularly between piano tunes and pure tones. Results also show no significant difference across test sessions. Conclusions These results suggest that a controlled test environment may not be required in spectral and temporal assessment for NH listeners. Under the quiet test environment, a single outcome measure is sufficient, but test orders should be counterbalanced.

scholarly journals Binocular responses and vertical strabismus

2007 ◽  
Vol 64 (2) ◽  
pp. 109-115 ◽  
Author(s):  
Dusica Risovic ◽  
Lidija Petrovic ◽  
Natalija Kosanovic-Jakovic ◽  
Katarina Misailovic ◽  
Branislav Stankovic ◽  
...  
Keyword(s):  
Binocular Vision ◽  
Oblique Muscle ◽  
Common Pattern ◽  
Inferior Oblique Muscle ◽  
Group I ◽  
Significant Difference ◽  
Before And After ◽  
Group Ii ◽  
Sensory Tests ◽  
Dissociated Vertical Deviation

Background/Aim. Elevation in adduction is the most common pattern of vertical strabismus, and it is mostly treated with surgery. The results of weaking of inferior oblique muscle are very changeable. The aim of this study was to evaluate binocular vision using sensory tests before and one and six months after the surgery. Methods. A total of 79 children were divided in two groups: the first, with inferior oblique muscle of overaction (n = 52), and the second with dissociated vertical deviation (DVD), and primary inferior oblique muscle overaction (n = 27). We tested them by polaroid mirror test (PMT), Worth test at distance and near, fusion amplitudes on sinoptofore, Lang I stereo test and Wirt-Titmus stereo test. We examined our patients before and two times after the surgery for vertical strabismus. Results. Foveal suppression in the group I was found in 60.5% of the patients before, and in 56.4% after the surgery. In group II Foveal suppression was detected in 64.7% of the patients before, but in 55.6% 6 months after the surgery with PMT. Worth test revealed suppression in 23.5% of the patients before, and in 40.7% after the vertical muscle surgery. Parafoveal fussion persisted in about 1/3 of the patients before the surgery, and their amplitudes were a little larger after the surgery in the group I patients. Lang I stereo test was negative in 53.9% before and 51.9% after the surgery in the group I, and in 48.2% of the patients before and after the surgery in the group II patients. Wirt-Titmus stereo test was negative in 74.5% of the patients before and in 72.9% after the surgery in the group I, but in the group II it was negative in 70.8% before and in 68.0% of the patients 6 months after the surgery. Conclusion. Binocular responses were found after surgery in 65.7% of the patients the group I and in 55.6% patients the group II. There was no significant difference between these two groups, but binocular responses were more often in the patients of the group I.

scholarly journals Volatile phenolics in Teran PTP red wine

2016 ◽  
Vol 107 (1) ◽  
pp. 5 ◽  
Author(s):  
Helena BAŠA ČESNIK ◽  
Klemen LISJAK
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Red Wine ◽  
Sensory Characteristics ◽  
Threshold Values ◽  
Odour Threshold

The volatile phenolics, 4-ethylphenol, 4-vinylphenol, 4-ethylguaiacol and 4-vinylguaiacol were quantified in Teran PTP wines that were produced in the Kras winegrowing district. The compounds were determined by using gas chromatography coupled with mass spectrometry after extraction with diethylether. Three years monitoring (2011, 2012, 2013 vintages) showed that all four undesirable compounds were identified in Teran PTP wines, however their content did not influence significantly the sensory characteristics of the wine. The average contents gained over the three-year period (2011-2013; n=82) were 153±193 µg L<sup>-1</sup> for 4-ethylphenol, 1265±682 µg L<sup>-1</sup> for 4-vinylphenol, 69±94 µg L<sup>-1</sup> for 4-ethylguaiacol and 128±106 µg L<sup>-1</sup> for 4-vinylguaiacol. 7.3 % of samples showed contents of 4-ethylphenol above the odour threshold values. For 4-vinylphenol, 4-ethylguaiacol and 4-vinylguaiacol that percentage was 98.8 %, 25.6 % and 91.5 %, respectively.

scholarly journals Quality Evaluation of Ogi from Acha (Digitaria exilis), Soybean (Glycine max) and Carrot (Daucus carota L.) Composite Flour

2019 ◽  
pp. 1-11
Author(s):  
Moses Terkula Ukeyima ◽  
Israel Okpunyi Acham ◽  
Comfort Temitope Awojide
Keyword(s):  
Functional Properties ◽  
Proximate Composition ◽  
Control Sample ◽  
Sensory Characteristics ◽  
Composite Flour ◽  
Soybean Flour ◽  
Overall Acceptability ◽  
Significant Difference ◽  
Constant Addition ◽  
Milk Flavor

Ogi was produced from composite flour of fermented Acha, roasted Soybean and Carrot.  The raw materials were blended in varying proportions. Proximate composition, functional properties and sensory characteristics of the formulated Ogi samples were evaluated. The results of the proximate composition showed a significant increase in moisture (5.36% to 9.94%), protein (3.94% to 16.98%), fat (1.89% to 10.23%), crude fiber (1.80% to 3.12%) and ash (0.35% to 0.99%); while a decrease was observed in carbohydrate (86.66% to 58.74%) with increase in supplementation with roasted Soybean flour and constant addition of carrot flour along with the milk flavor. The functional properties showed significant increase in foam capacity (5.99% to 7.97%), Swelling index (2.46 v/v to 3.08 v/v) and Least gelation capacity (8.10% to 14.0%); while a decrease was observed in bulk density (0.84 g/mL to 0.72 g/mL), water absorption capacity (1.40% to 1.10%) and foaming stability (3.39% to 2.79%). Sensory characteristics result revealed that there was no significant difference (p<0.05) in aroma and overall acceptability with increasing incorporation of roasted Soybean flour and constant addition of Carrot flour with milk flavor. Aside the control sample (containing 100% fermented Acha flour) there was preference for Sample C (70% fermented Acha flour: 15% roasted Soybean flour: 10% Carrot flour: 5% Milk flavor) and Sample D (60% fermented Acha flour: 25% roasted Soybean flour: 10% `Carrot flour: 5% Milk flavor) in terms of color (6.65 and 6.25), taste (6.95 and 6.35), aroma (6.45 and 6.30), mouth feel (6.10 and 6.35) and overall acceptability (6.50 and 6.50) respectively, among the blend formulations. Supplementation of fermented Acha with roasted Soybean and Carrot flour considerably increased the protein and fat contents of the blend; hence Soybean should be used for supplementation of cereal based product in order to improve their nutritional composition.

scholarly journals Pengaruh Substitusi Tepung Kedelai terhadap Kualitas Biskuit

Media Wisata ◽  
2021 ◽  
Vol 16 (2) ◽  
Author(s):  
Heni Susilowati ◽  
Adi Prabowo
Keyword(s):  
Sampling Technique ◽  
Subjective Assessment ◽  
Soy Flour ◽  
P Value ◽  
Homogeneity Test ◽  
Soybean Flour ◽  
Normality Test ◽  
Significant Difference ◽  
Different Types ◽  
Sensory Tests

The research entitled The Effect of Substitution of Soybean Flour on Biscuit Quality is a type of research using a quantitative approach with an experimental method. The purpose is to know the effect of quality biscuits with soybean flour substitution with a different percentage that is equal to 50%, 25% and 10% viewed from the aspect of colour, flavour, aroma and texture. The experiments used 3 different types of treatment on the percentage of soy flour used ie, biscuit A with 50% soy flour, biscuit B with 25% soy flour, and C biscuits with 10% soy flour. Methods of data collection using subjective assessment of sensory tests taken from the results of a panellist assessment that includes assessment of colour, aroma, taste and texture on biscuits. The panel of researchers was 30 people taken by random sampling technique with considerations that included panellist knowledge about the sensory properties of biscuits in general. Methods of data analysis to test the hypothesis using the analysis of single classification variables and Tukey test, previously conducted precariat test that is homogeneity test and normality test. The result of the research with Anova test seen from the color aspect shows that (significant value (p-value) <0,05 = 0,000 <0,05) shows that there is significant difference from three substitution biscuit substitution biscuit, while from aroma aspect shows significant (p-value) <0,05 = 0,008 <0,05) indicated that there were significant differences from the three soybean substitution biscuit samples. Seen from the texture aspect showed (significant value (p-value) <0,05 = 0,000 <0,05) indicated that there was significant difference from three sample of soybean substitution biscuit. In terms of taste taste (significant value (p-value) <0.05 = 0.005 <0.05) indicates that there are significant differences from the three soybean substitution biscuit samples.

scholarly journals Ejaculatory Pain

2007 ◽  
Vol 107 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Eske K. Aasvang ◽  
Bo Møhl ◽  
Henrik Kehlet
Keyword(s):  
Chronic Pain ◽  
Sexual Dysfunction ◽  
Quantitative Sensory Testing ◽  
Groin Hernia ◽  
Pain Treatment ◽  
Detection Threshold ◽  
Control Group ◽  
Sensory Testing ◽  
Detection Thresholds ◽  
Pain Detection

Background Sexual dysfunction due to ejaculatory and genital pain after groin hernia surgery may occur in approximately 2.5% of patients. However, the specific psychosexological and neurophysiologic characteristics have not been described, thereby precluding assessment of pathogenic mechanisms and treatment strategies. Methods Ten patients with severe pain-related sexual dysfunction and ejaculatory pain were assessed in detail by quantitative sensory testing and interviewed by a psychologist specialized in evaluating sexual functional disorders and were compared with a control group of 20 patients with chronic pain after groin hernia repair but without sexual dysfunction, to identify sensory changes associated with ejaculatory pain. Results Quantitative sensory testing showed significantly higher thermal and mechanical detection thresholds and lowered mechanical pain detection thresholds in both groups compared with the nonpainful side. Pressure pain detection threshold and tolerance were significantly lower in the ejaculatory pain group compared with the control group. 'The maximum pain was specifically located at the external inguinal annulus in all ejaculatory pain patients, but not in controls. The psychosexual interview revealed no major psychosexual disturbances and concluded that the pain was of somatic origin. All patients with ejaculatory pain had experienced major negative life changes and deterioration in their overall quality of life and sexual function as a result of the hernia operation. Conclusions Postherniotomy ejaculatory pain and pain-related sexual dysfunction is a specific chronic pain state that may be caused by pathology involving the vas deferens and/or nerve damage. Therapeutic strategies should therefore include neuropathic pain treatment and/or surgical exploration.

scholarly journals PEMANFAATAN EKSTRAK BELIMBING WULUH DAN EKSTRAK KULIT BUAH NAGA DALAM PEMBUATAN SELAI

2021 ◽  
Vol 8 (2) ◽  
pp. 62
Author(s):  
Nurul Aini ◽  
Dody Handito ◽  
Siska Cicilia
Keyword(s):  
Antioxidant Activity ◽  
Vitamin C ◽  
Block Design ◽  
Fruit Peel ◽  
Significance Level ◽  
Randomized Block Design ◽  
Dragon Fruit ◽  
Significant Difference ◽  
Sensory Tests

This study aims to determine the concentration of starfruit juice and dragon fruit peel on the quality of jam. The experimental design used was a one-factor Randomized Block Design (RAK) with six treatments and three replications to obtain 18 samples. The treatments were the concentration of starfruit juice and dragon fruit peel extract with P1 (100% : 0%), P2 (85% : 15%), P3 (70% : 15%), P4 (55% : 45%), P5 ( 40% : 60%) and P6 (25% : 75%). Parameters observed were vitamin C levels, antioxidant activity, spread, and color as well as sensory tests (color, aroma, and taste). Data analysis results were tested by analysis of variance at a significance level of 5% using Co-Stat software. If there is a significant difference, then the orthogonal polynomial further test is carried out, while the physical and sensory tests are further tested using the Honest Significant Difference test at a significance level of 5%. The results showed that the concentration of star fruit juice and dragon fruit pulp did not have a different effect on vitamin C levels but had a significantly different effect on antioxidant activity, spread, and color. P6 treatment resulted in the highest antioxidant activity of 77.27%, 12.80 mg of vitamin C content, 10.1 cm of smearing power, and sensory properties that were acceptable to the panelists.

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