scholarly journals Investigating unique hues at different chroma levels with a smaller hue angle step

2020 ◽  
Vol 37 (4) ◽  
pp. 671
Author(s):  
Wenyu Bao ◽  
Minchen Wei ◽  
Kaida Xiao
Keyword(s):  
HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 510f-511 ◽  
Author(s):  
D.C. Ferree ◽  
S.J. McArtney ◽  
D.M. Scurlock

Four French–American hybrid grape cultivars grown in a greenhouse were subjected to 5 days of 80% shade at four different times around bloom. Fruit set of `Seyval' was reduced by shade imposed before, during, or immediately after bloom. `Vidal' and `Chambourcin' were less sensitive, with fruit set reduced only by shade at bloom. Shade had little effect on fruit set of `DeChaunac'. In a second study, `Chambourcin' vines were exposed to ambient, ambient plus supplemental lights, and 30%, 50%, or 80% shade for 5 weeks beginning just prior to bloom. Fruit set was positively related to light intensity. At harvest, soluble solids, pH, and hue angle had a negative linear relationship to light level. Fruit color developed earliest and most rapidly with the reduced light treatments applied at bloom. Cluster weight was positively related to light intensity.


Agriculture ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 702
Author(s):  
Monika Kędzierska-Matysek ◽  
Anna Teter ◽  
Małgorzata Stryjecka ◽  
Piotr Skałecki ◽  
Piotr Domaradzki ◽  
...  

The antioxidant activity of honey depends on the botanical origin, which also determines their physicochemical properties. In this study, a multivariate analysis was used to confirm potential relationships between the antioxidant properties and colour parameters, as well as the content of seven elements in five types of artisanal honey (rapeseed, buckwheat, linden, black locust, and multifloral). The type of honey was found to significantly influence most of its physicochemical properties, colour parameters, and the content of potassium, manganese and copper. Antioxidant parameters were shown to be significantly positively correlated with redness and concentrations of copper and manganese, but negatively correlated with the hue angle and lightness. The principal component analysis confirmed that the darkest buckwheat honey had the highest antioxidant activity in combination with its specific colour parameters and content of antioxidant minerals (manganese, copper and zinc). The level of these parameters can be potentially used for the identification of buckwheat honey.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2247
Author(s):  
Mirosław Słowiński ◽  
Joanna Miazek ◽  
Krzysztof Dasiewicz ◽  
Marta Chmiel

A beneficial aspect of the use of fiber preparations in the meat industry is the improvement of some quality characteristics of meat products. However, the preparation added in the amount of 3 or 6% may affect their color. The effect of the addition of barley, wheat and oat fiber preparations with different fiber lengths, in quantities allowing the product to be indicated as “high in fiber” or “source of fiber”, to pasteurized or sterilized medium-grounded canned meat products on their color, was determined. In the obtained canned meat products, the basic chemical composition and the L*, a* and b*, C* (Chroma) and h* (hue angle) color components were determined. The addition of the barley fiber preparation BG 300 to the model canned meat products caused a significant (p ≤ 0.05) darkening and an increase in the proportion of yellow color. In an industrial practice, this may result in poorer consumer acceptance of the meat product. Fiber length of wheat and barley fiber had no effect on the color components of products. The 6% addition of the wheat fiber preparations WF 200R and WF 600R or the oat fiber preparations HF 200 and HF 600 caused an apparent lightening of their color (ΔE > 2) compared to the control products.


2019 ◽  
Vol 23 (4) ◽  
pp. 340-354
Author(s):  
Asim Kumar Roy Choudhury ◽  
Biswajit Naskar

Purpose This paper aims to compare visual (Munsell) and instrumental (CIELAB) attributes of SCOTDIC colour standards. Design/methodology/approach SCOTDIC cotton and polyester standards of defined hue, value and chroma were subjected to spectrophotometric assessment for finding the corresponding instrumental parameters. The visual and instrumental parameters were compared. Findings The correlation between SCOTDIC value and CIELAB lightness is quite high. Correlation coefficient between SCOTDIC hue and CIELAB hue angle and the correlation between SCOTDIC chroma and CIELAB chroma were only moderate because the CIELAB chroma varied widely at higher chroma. When the standards of SCOTDIC hues having erratic hue angles at two extremes are excluded, the Correlation coefficients between SCOTDIC hue and CIELAB hue angle become high. Research limitations/implications The psychophysical data (visual) are difficult to match with physical data (instrumental). Originality/value The object of the present research is to study and compare visual (Munsell) and instrumental (CIELAB) colorimetric parameters. Munsell scale is physically exemplified by SCOTDIC fabric samples available in two sets, namely, cotton and polyester sets.


2006 ◽  
Vol 23 (3-4) ◽  
pp. 331-339 ◽  
Author(s):  
DAVID L. PHILIPONA ◽  
J. KEVIN O'REGAN

Psychophysical studies suggest that different colors have different perceptual status: red and blue for example are thought of as elementary sensations whereas yellowish green is not. The dominant account for such perceptual asymmetries attributes them to specificities of the neuronal representation of colors. Alternative accounts involve cultural or linguistic arguments. What these accounts have in common is the idea that there are no asymmetries in the physics of light and surfaces that could underlie the perceptual structure of colors, and this is why neuronal or cultural processes must be invoked as the essential underlying mechanisms that structure color perception. Here, we suggest a biological approach for surface reflection properties that takes into account only the information about light that is accessible to an organism given the photopigments it possesses, and we show that now asymmetries appear in the behavior of surfaces with respect to light. These asymmetries provide a classification of surface properties that turns out to be identical to the one observed in linguistic color categorization across numerous cultures, as pinned down by cross cultural studies. Further, we show that data from psychophysical studies about unique hues and hue cancellation are consistent with the viewpoint that stimuli reported by observers as special are those associated with this singularity-based categorization of surfaces under a standard illuminant. The approach predicts that unique blue and unique yellow should be aligned in chromatic space while unique red and unique green should not, a fact usually conjectured to result from nonlinearities in chromatic pathways.


2019 ◽  
Vol 3 (2) ◽  
Author(s):  
H. D. Garnica ◽  
M. F. Miller ◽  
D. A. Vargas ◽  
A. R. English ◽  
K. E. Hanlon ◽  
...  

ObjectivesThe purpose of the study was to evaluate color changes during dark storage of ground pork following application with one of three different antimicrobial interventions to pork trim.Materials and MethodsTreatments included a control (no antimicrobial), lactic acid (LA; 3%), PAA+Titon [sulfuric acid and sodium sulfate (pH 1.3) combined with peracetic acid (350 ppm)], PAA+Acetic [peracetic acid (400 ppm) with 2% acetic acid]. Four 22.7-kg batches of pork trim were treated with one intervention, ground [coarse (3/16’’) followed by a fine (1/8”) grind] and packaged in 454-g rollstock vacuum packaging (n = 40/treatment). After random assignment to an aging time (0, 7, 14, 21, or 28 d), product was held under dark storage at 2–4°C. On each storage day, samples (n = 8/treatment) were opened and L*, a*, and b* values were taken using a HunterLab Miniscan XE spectrophotometer at 0 min, 10 min, and 20 min for bloom color analysis, with hue angle [arctangent (b*/a*)] and chroma [ (a* + b*)1/2 ] calculated from a* and b* values. For pH, 5 g of sample and 90 mL of distillated water were homogenized and analyzed with a bench top pH probe. Finally, fat, moisture, and protein percentage were determined using a FOSS FoodScan. Statistical analysis was conducted using the GLM procedure of SAS with a means separation using the Tukey adjustment and significance set at P < 0.05.ResultsProximate analysis of the ground pork in this study showed 20.04 ± 1.13% for fat, 61.15 ± 1.11% for moisture, and 16.83 ± 0.39% for protein content. For initial pork color, at 0 min, LA had greater L* values compared to PAA+Titon at 0d, 7d and 14d (P < 0.05), but no treatment differences were detected in L* values at 21d and 28d (P > 0.05). After 10 min of bloom time, PAA+Titon maintained the highest chroma value throughout all aging days (P < 0.05) demonstrating the most color intensity. At 21d PAA+Titon increased blooming properties through 20min (P < 0.05), based on a*, while control samples had no bloom development (P > 0.05). At 21d and 28d aging LA hue angle was highest (P < 0.05) indicating more potential metmyoglobin discoloration. PAA+Titon presented the highest pH values compared to all the other treatments for each day during the storage period except for Day 14, while LA presented lower values compared to all the other treatments for each day (P < 0.05).ConclusionAs an organic acid application on pork trim prior to grinding, PAA+Titon demonstrates positive effects on color of ground pork based on color and pH values, after post-grinding storage.


2002 ◽  
Vol 2 (10) ◽  
pp. 55-55
Author(s):  
E. Miyahara ◽  
E. A. Szewczyk ◽  
C. R. Holloway
Keyword(s):  

2018 ◽  
Vol 8 (4) ◽  
pp. 544-554 ◽  
Author(s):  
Marcio Gama Dos Santos da Costa ◽  
Luiz Carlos Chamhum Salomão ◽  
Dalmo Lopes de Siqueira ◽  
Paulo Roberto Cecon ◽  
César Fernandes Aquino ◽  
...  

The objective of the study was to elucidate the best combination of ethylene dose and exposure time aiming the degreening of ‘Ponkan’ tangerines. Fruits harvested with fully green peel were placed in airtight boxes, exposed during 24, 48 and 96 h to ethylene gas at concentrations of 0, 5, 10, 20 and 40 µL L-1, at a temperature of 20 ± 1°C and 90 ± 5% of relative humidity. On every 24 h the fruits were evaluated for color, Hue angle, total chlorophyll and carotenoids in the peel, solutes leakage, soluble solids, titrable acidity, CO2 production and fresh fruit weight loss. The degreening was more pronounced in fruits exposed to ethylene for 96 h, independently the concentration. The electrolytes leakage peel increased linearly in fruit-control and those exposed to ethylene for 24 h. In fruits treated for 48 and 96 h, electrolyte leakage was observed only during ethylene exposure. The accumulated fresh mass loss did not exceeded 1% in the fruits. The ethylene dose did not affected the fruit respiratory behavior. The best combination aiming fruit degreening was the exposure during 96 h with 5 μL L-1 of ethylene, followed by 48 to 72 hours of storage after treatment.


Author(s):  
Jakellinye Miranda ◽  
Suélen Braga de Andrade, Andressa Vighi Schiavon ◽  
Pedro Luis Panisson Kaltbach Lemos ◽  
Cláudia Simone Madruga Lima ◽  
Marcelo Barbosa Malgarim

Peach is a climacteric highly-perishable fruit whose post-harvest preservation relies largely on cold storage. The combination of the last with other technologies allows to extend the shelf life of this product. One alternative is the utilization of salicylic acid, a natural compound involved in many physiological phenomena such as resistance against diseases and ripening. Considering these facts, the objective of the present work was to evaluate the effect of pre-harvest application of salicylic acid solutions on the quality of ‘Chimarrita’ peaches during post-harvest cold storage. The experiment was conducted at the Federal University of Pelotas/RS, in the campus of Capão do Leão/RS - Brazil. The application of salicylic acid solutions was performed by direct pulverization on the fruits, 30 days prior to harvest. The concentrations were: 0,0 (control); 1,0; 1,5; and 2,0 mM. After harvest, the fruits were stored in a cold chamber at 1,0 ± 0,5°C and 85-90% RH, for 30 days. The analyses were performed at the following cold storage periods (plus 2 days at room temperature of 20°C to all treatments, in order to simulate commercialization conditions): 10 (+2) days; 20 (+2) days; e 30 (+2) days. The variables evaluated were: mass loss (%); flesh firmness (N); DA index; color (L, a*, b* and hue angle); wooliness incidence (%); rot incidence (%); total soluble solids (°Brix); pH; titrable acidity (% of organic acids); and ratio. The salicylic acid doses and/or the cold storage periods had significant effects on all the evaluated parameters. For most of the parameters analyzed, the intermediate dosis of 1mM (and also 1,5mM) of salicilic acid showed the most promising results. Therefore, the application of salicylic acid solutions 30 days prior to harvest is a technique which can be combined to cold storage in order to shift the quality and the shelf-life of ‘Chimarrita’ peaches.


2020 ◽  
Vol 2 (02) ◽  
pp. 48
Author(s):  
Diah Mustika Lukitasari ◽  
Renny Indrawati ◽  
Rosita Dwi Chandra ◽  
Heriyanto Heriyanto ◽  
Leenawaty Limantara

It has been known that most natural pigments are unstable upon exposure against several environmental factors, such as thermal treatment, light, oxidizing or reducing agents, as well as acid or alkaline compounds. Encapsulation procedures is often adopted to adjust the solubility and provide protection to the natural pigments. Here, we prepared an encapsulated beetroot extract as the candidate of red bio-colorant. The primary aim of the present study is to investigate color alteration of encapsulated beetroot (Beta vulgaris L.) extract upon dissolving in various pH adjustment and prolonged storage. The McIllvainne buffer was prepared in various pH range, i.e. from 2 to 11. The encapsulated extract (0.1% w/v) was dissolved and the color of the solutions were measured regularly until 3 days storage under darkness at 200C. Any degradation or structural changes will cause color alteration, which were monitored through L*, a*, b* values, the hue angle (H°), chroma values (C), as well as color difference (DE). The results showed that pH 4 was the most favorable condition that brings least impact to the color alteration, even when the colored solution was kept in prolonged storage until 9 days.


Sign in / Sign up

Export Citation Format

Share Document