The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Francisco J. Heredia - One of the best experts on this subject based on the ideXlab platform.
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Stenocereus griseus (Haw) pitaya as source of natural colourant: technological stability of colour and individual betalains
International Journal of Food Science and Technology, 2019Co-Authors: María Jesús Cejudo-bastante, Nelson Hurtado, Pablo Muñoz‐burguillos, Francisco J. HerediaAbstract:Stenocereus griseus pitaya has been evaluated as potential natural colourant on the basis of tristimulus colorimetry, differential colorimetry, and individual betalains, not previously conducted in conjunction with this raw material. Different technological treatment conditions were reproduced based on different pHs, temperatures and storage time. According to the results, cold temperatures (4 °C) maintained for longer the initial colour characteristics (L*, Cab∗ and hₐb) of the extracts, whereas hₐb modifications began from the commencement of treatment at room temperature. Highly acidic extracts (pH 4) were the most stable samples in the light of the lower hₐb and Cab∗ changes over time, even at room temperature. Betanin, isobetanin, betanidin and 2‐decarboxy‐neobetanin were more affected by temperature, whereas the content of the minor betalains significantly (P 3) were observed among all pH values and temperatures.
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effect of addition of overripe seeds from white grape by products during red wine fermentation on wine colour and phenolic composition
Lwt - Food Science and Technology, 2017Co-Authors: Francisco J Rivero, Lourdes M Gonzalezmiret, Belen Gordillo, Jose M Jarapalacios, Francisco J. HerediaAbstract:Abstract The effect of the fermentative addition of overripe seeds by-product (Pedro Ximenez white grapes, 3 g/L) on the phenolic composition and colour of red wines was studied by rapid resolution liquid chromatography (RRLC-MS) and Differential Colorimetry. Overripe seeds summited to postharvest dehydration by sun drying directly demonstrated were rich in phenolics such as gallic acid, epicatechin, and procyanidin B2 3- O -gallate, and hence a source of copigments capable to stabilize wine anthocyanins. The fermentative addition of overripe seeds led to Syrah wines with significant higher content of anthocyanins and procyanidins than traditional macerated wines, which had a positive effect on colour quality and stability. With respect to the colour quality, visually perceptible colour differences were found respect to the traditional macerated wines (ΔE* ab > 3), getting overripe seeds macerated wines with bluish hues and higher chroma values. Moreover, Differential Colorimetry demonstrated that the addition of overripe seeds induces lower colour modification in wines during stabilization and, in consequence, higher colour stability.
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potential use of new colombian sources of betalains color stability of ulluco ullucus tuberosus extracts under different ph and thermal conditions
Food Research International, 2014Co-Authors: Maria Jesus Cejudobastante, Nelson Hurtado, Natalia Mosquera, Francisco J. HerediaAbstract:The potential use of ulluco (Ullucus tuberosus) extracts to be added as natural colorant to other products has been studied. The stability of ulluco extracts at different pHs and temperatures over time has been thoroughly conducted. Our attention was focused on the tristimulus colorimetry, differential colorimetry and betalains related to color. On the basis of the results, although ulluco extract adjusted to pH 4 showed a significantly lower color intensity (C*ab ~ 40), the stability of red hue (hab) over time was higher. Betalain content showed the same trend, and lower values in highly-acidic extracts have been reported. It could be also affirmed that visually appreciable color changes (ΔE*ab > 2) were induced when pH changed and different temperatures were applied. Despite of the vivid red color of the initial extracts, ulluco extracts added to low-acidic foodstuffs showed a tendency towards yellowish tonalities (values of hab from 45° to 80°), mitigated by using refrigeration storage conditions (hab values from 45° to 55°).
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effect of the time of cold maceration on the evolution of phenolic compounds and colour of syrah wines elaborated in warm climate
International Journal of Food Science and Technology, 2014Co-Authors: Maria Jesus Cejudobastante, Belen Gordillo, Dolores Hernanz, M L Escuderogilete, M L Gonzalezmiret, Francisco J. HerediaAbstract:Summary The effect of different cold maceration times on Syrah red wines from warm climate has been evaluated. Differential colorimetry and tristimulus colorimetry were applied to colour data at different points of the vinification stage. Virtually, all the phenolic compounds showed significantly higher content in cold macerated wines, even more when longer contact time was used. Long cold macerated (LCM) wines had the significantly (P < 0.05) highest chroma values (C*ab) and lowest of lightness (L*) and hue (hab). Unexpectedly, wines submitted to short-time cold maceration (SCM) presented the lowest chroma values, even significantly inferior to that observed in traditional macerated (TM) wines. Moreover, colour changes (ΔE*ab) between TM and SCM were mainly quantitative (%Δ2L and %Δ2C), whereas they were also qualitative when compared TM with LCM (%Δ2C and %Δ2H). Cold maceration in warm climates characterised by common colour losses must be carefully employed because undesirable consequences on colour may occur.
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application of the differential colorimetry and polyphenolic profile to the evaluation of the chromatic quality of tempranillo red wines elaborated in warm climate influence of the presence of oak wood chips during fermentation
Food Chemistry, 2013Co-Authors: Belen Gordillo, Maria Jesus Cejudobastante, Francisco J Rodriguezpulido, Lourdes M Gonzalezmiret, Francisco J. HerediaAbstract:Abstract The effect of adding American oak wood chips during fermentation on Tempranillo red wines elaborates in a warm climate has been studied. Our attention was focused on the tristimulus colorimetry, differential colorimetry and phenolic compounds related to wine colour. This technique was applied as an oenological alternative to the conventional winemaking for avoiding the common fall of colour of red wines elaborated in warm climates. The addition of oak wood chips promoted the colour enhancement and stabilisation, producing wines with a notably darker colour and with more bluish tonality. This fact was also related to the significantly higher content of some phenolic compounds. On the basis of the results, it could be affirmed that the addition of oak wood chips during fermentation induced visually perceptible colour changes (by the analysis of Δ E ab ∗ , %Δ2L, %Δ2C and %Δ2H), mainly in a quantitative way, and also a lower percentage of diminution of colour.
Lucy Chai See Lum - One of the best experts on this subject based on the ideXlab platform.
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assessing dehydration status in dengue patients using urine Colourimetry and mobile phone technology
PLOS Neglected Tropical Diseases, 2020Co-Authors: Natalie Chew, Abdul Muhaimin Noor Azhar, Aida Bustam, Mohamad Shafiq Azanan, Crystal Wang, Lucy Chai See LumAbstract:Background Dengue is a systemic and dynamic disease with symptoms ranging from undifferentiated fever to dengue shock syndrome. Assessment of patients’ severity of dehydration is integral to appropriate care and management. Urine colour has been shown to have a high correlation with overall assessment of hydration status. This study tests the feasibility of measuring dehydration severity in dengue fever patients by comparing urine colour captured by mobile phone cameras to established laboratory parameters. Methodology/Principal findings Photos of urine samples were taken in a customized photo booth, then processed using Adobe Photoshop to index urine colour into the red, green, and blue (RGB) colour space and assigned a unique RGB value. The RGB values were then correlated with patients’ clinical and laboratory hydration indices using Pearson’s correlation and multiple linear regression. There were strong correlations between urine osmolality and the RGB of urine colour, with r = -0.701 (red), r = -0.741 (green), and r = -0.761 (blue) (all p-value <0.05). There were strong correlations between urine specific gravity and the RGB of urine colour, with r = -0.759 (red), r = -0.785 (green), and r = -0.820 (blue) (all p-value <0.05). The blue component had the highest correlations with urine specific gravity and urine osmolality. There were moderate correlations between RGB components and serum urea, at r = -0.338 (red), -0.329 (green), -0.360 (blue). In terms of urine biochemical parameters linked to dehydration, multiple linear regression studies showed that the green Colourimetry code was predictive of urine osmolality (β coefficient -0.082, p-value <0.001) while the blue Colourimetry code was predictive of urine specific gravity (β coefficient -2,946.255, p-value 0.007). Conclusions/Significance Urine Colourimetry using mobile phones was highly correlated with the hydration status of dengue patients, making it a potentially useful hydration status tool.
Kyoichi Mizuno - One of the best experts on this subject based on the ideXlab platform.
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relationship between thin cap fibroatheroma identified by virtual histology and angioscopic yellow plaque in quantitative analysis with colorimetry
Circulation, 2009Co-Authors: Masanori Yamamoto, Masamichi Takano, Kentaro Okamatsu, Daisuke Murakami, Shigenobu Inami, Yong Xie, Koji Seimiya, Takayoshi Ohba, Yoshihiko Seino, Kyoichi MizunoAbstract:Background: Thin cap fibroatheroma (TCFA) is considered to be a vulnerable plaque. Virtual Histology-intravascular ultrasound (VH-IVUS) can precisely identify TCFA in vivo. Intense yellow plaque on angioscopy determined by quantitative colorimetry with L*a*b* color space corresponds with histological TCFA; in particular, a plaque of color b* value >23 indicates an atheroma with a fibrous cap thickness 10% of plaque area without overlying fibrous tissue, and angioscopic TCFA was a plaque with b* value >23. The frequency of angioscopic TCFA was higher in the VH-TCFA group than in the VH-non-TCFA group (74% vs 23%, P=0.0002). Moreover, yellow color intensity (b* value) significantly correlated with plaque classification on VH-IVUS. When TCFA detected with angioscopy was used as the gold standard, the sensitivity, specificity, and accuracy for TCFA with VH-IVUS was 68%, 81%, and 75%, respectively. Conclusions: VH-TCFA strongly correlated with angioscopic TCFA determined by a quantitative analysis with colorimetry. (Circ J 2009; 73: 497 - 502)
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high yellow color intensity by angioscopy with quantitative colorimetry to identify high risk features in culprit lesions of patients with acute coronary syndromes
American Journal of Cardiology, 2007Co-Authors: Fumiyuki Ishibashi, Kyoichi Mizuno, Akio Kawamura, Premranjan P Singh, Richard W Nesto, Sergio WaxmanAbstract:High yellow color intensity (HYCI) regions of atherosclerotic plaque, determined by angioscopy with quantitative colorimetry, are associated with lipid cores underneath thin fibrous caps in ex vivo tissue samples. To determine whether HYCI regions of coronary plaque are associated with disruption or thrombus in living patients, quantitative colorimetry was applied to angioscopy, and the color of culprit lesions was measured in patients with acute coronary syndromes. In 46 patients with acute coronary syndromes (acute myocardial infarction, n = 14; unstable angina pectoris [UAP] with culprit thrombus, n = 16; and UAP without culprit thrombus, n = 16), the recorded angioscopic images of culprit lesions were analyzed using a quantitative colorimetric method based on the L*a*b* color space applied to angioscopy (positive b* = yellow color intensity). HYCI was defined as b* value >23. Plaque disruption was significantly more prevalent in 19 of 24 HYCI regions (79%) than in 9 of 22 non-HYCI regions (41%) (p = 0.007). Culprit HYCI regions were prevalent in patients with myocardial infarction (11 of 14 [79%]), followed by those with UAP with thrombus (9 of 16 [56%]) and UAP without thrombus (4 of 16 [25%]) (p = 0.01 for trend), and were significantly more prevalent in 66% of patients with myocardial infarction and UAP with thrombus compared with 25% of those with UAP without thrombus (p = 0.007). In conclusion, HYCI regions of coronary plaque may be indicative of high-risk lesions vulnerable to thrombosis. Coronary angioscopy with quantitative colorimetry could be used to study the association between high-risk coronary lesions and future cardiovascular events.
Natalie Chew - One of the best experts on this subject based on the ideXlab platform.
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assessing dehydration status in dengue patients using urine Colourimetry and mobile phone technology
PLOS Neglected Tropical Diseases, 2020Co-Authors: Natalie Chew, Abdul Muhaimin Noor Azhar, Aida Bustam, Mohamad Shafiq Azanan, Crystal Wang, Lucy Chai See LumAbstract:Background Dengue is a systemic and dynamic disease with symptoms ranging from undifferentiated fever to dengue shock syndrome. Assessment of patients’ severity of dehydration is integral to appropriate care and management. Urine colour has been shown to have a high correlation with overall assessment of hydration status. This study tests the feasibility of measuring dehydration severity in dengue fever patients by comparing urine colour captured by mobile phone cameras to established laboratory parameters. Methodology/Principal findings Photos of urine samples were taken in a customized photo booth, then processed using Adobe Photoshop to index urine colour into the red, green, and blue (RGB) colour space and assigned a unique RGB value. The RGB values were then correlated with patients’ clinical and laboratory hydration indices using Pearson’s correlation and multiple linear regression. There were strong correlations between urine osmolality and the RGB of urine colour, with r = -0.701 (red), r = -0.741 (green), and r = -0.761 (blue) (all p-value <0.05). There were strong correlations between urine specific gravity and the RGB of urine colour, with r = -0.759 (red), r = -0.785 (green), and r = -0.820 (blue) (all p-value <0.05). The blue component had the highest correlations with urine specific gravity and urine osmolality. There were moderate correlations between RGB components and serum urea, at r = -0.338 (red), -0.329 (green), -0.360 (blue). In terms of urine biochemical parameters linked to dehydration, multiple linear regression studies showed that the green Colourimetry code was predictive of urine osmolality (β coefficient -0.082, p-value <0.001) while the blue Colourimetry code was predictive of urine specific gravity (β coefficient -2,946.255, p-value 0.007). Conclusions/Significance Urine Colourimetry using mobile phones was highly correlated with the hydration status of dengue patients, making it a potentially useful hydration status tool.
Maria Jesus Cejudobastante - One of the best experts on this subject based on the ideXlab platform.
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potential use of new colombian sources of betalains color stability of ulluco ullucus tuberosus extracts under different ph and thermal conditions
Food Research International, 2014Co-Authors: Maria Jesus Cejudobastante, Nelson Hurtado, Natalia Mosquera, Francisco J. HerediaAbstract:The potential use of ulluco (Ullucus tuberosus) extracts to be added as natural colorant to other products has been studied. The stability of ulluco extracts at different pHs and temperatures over time has been thoroughly conducted. Our attention was focused on the tristimulus colorimetry, differential colorimetry and betalains related to color. On the basis of the results, although ulluco extract adjusted to pH 4 showed a significantly lower color intensity (C*ab ~ 40), the stability of red hue (hab) over time was higher. Betalain content showed the same trend, and lower values in highly-acidic extracts have been reported. It could be also affirmed that visually appreciable color changes (ΔE*ab > 2) were induced when pH changed and different temperatures were applied. Despite of the vivid red color of the initial extracts, ulluco extracts added to low-acidic foodstuffs showed a tendency towards yellowish tonalities (values of hab from 45° to 80°), mitigated by using refrigeration storage conditions (hab values from 45° to 55°).
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effect of the time of cold maceration on the evolution of phenolic compounds and colour of syrah wines elaborated in warm climate
International Journal of Food Science and Technology, 2014Co-Authors: Maria Jesus Cejudobastante, Belen Gordillo, Dolores Hernanz, M L Escuderogilete, M L Gonzalezmiret, Francisco J. HerediaAbstract:Summary The effect of different cold maceration times on Syrah red wines from warm climate has been evaluated. Differential colorimetry and tristimulus colorimetry were applied to colour data at different points of the vinification stage. Virtually, all the phenolic compounds showed significantly higher content in cold macerated wines, even more when longer contact time was used. Long cold macerated (LCM) wines had the significantly (P < 0.05) highest chroma values (C*ab) and lowest of lightness (L*) and hue (hab). Unexpectedly, wines submitted to short-time cold maceration (SCM) presented the lowest chroma values, even significantly inferior to that observed in traditional macerated (TM) wines. Moreover, colour changes (ΔE*ab) between TM and SCM were mainly quantitative (%Δ2L and %Δ2C), whereas they were also qualitative when compared TM with LCM (%Δ2C and %Δ2H). Cold maceration in warm climates characterised by common colour losses must be carefully employed because undesirable consequences on colour may occur.
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application of the differential colorimetry and polyphenolic profile to the evaluation of the chromatic quality of tempranillo red wines elaborated in warm climate influence of the presence of oak wood chips during fermentation
Food Chemistry, 2013Co-Authors: Belen Gordillo, Maria Jesus Cejudobastante, Francisco J Rodriguezpulido, Lourdes M Gonzalezmiret, Francisco J. HerediaAbstract:Abstract The effect of adding American oak wood chips during fermentation on Tempranillo red wines elaborates in a warm climate has been studied. Our attention was focused on the tristimulus colorimetry, differential colorimetry and phenolic compounds related to wine colour. This technique was applied as an oenological alternative to the conventional winemaking for avoiding the common fall of colour of red wines elaborated in warm climates. The addition of oak wood chips promoted the colour enhancement and stabilisation, producing wines with a notably darker colour and with more bluish tonality. This fact was also related to the significantly higher content of some phenolic compounds. On the basis of the results, it could be affirmed that the addition of oak wood chips during fermentation induced visually perceptible colour changes (by the analysis of Δ E ab ∗ , %Δ2L, %Δ2C and %Δ2H), mainly in a quantitative way, and also a lower percentage of diminution of colour.