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1.
Molecules ; 28(9)2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37175272

RESUMEN

Prickly pear fruits are seasonal and have shades ranging from pale green to deep purple. Their pigments are associated with bioactive compounds, being sensitive to thermal transformation processes for their conservation. The objective of this research was to evaluate the bioactive compounds and the sensory analysis of freeze-dried prickly pear fruits from an inter-Andean valley in Peru. The prickly pear fruits of the morada, anaranjada, and blanca ecotypes came from an inter-Andean valley in Peru at 2972 m altitude. The sliced fruits were freeze-dried at -40 °C and 0.25 mTorr, and the total polyphenol content (TPC), vitamin C, and antioxidant activity (AA) were determined, as well as the color L* a* b*, color index (CI*), FTIR spectra, and mineral content. In the same way, sensory analysis of preferences with nine scales was applied. It was observed that in the freeze-dried fruits, TPC, AA, and vitamin C increased significantly (p-value < 0.05), and their corresponding functional groups increased in intensity in their corresponding FTIR spectra; furthermore, trace elements such as Cu, Fe, Se, Zn, Si, and Mn were identified. On the other hand, freeze-drying provided deeper colors to the fruits, which most panelists said they "very much liked" during the sensory analysis, although the texture was not very well accepted, with most panelists reporting being "indifferent" towards it. The freeze-drying technique allows the bioactive and sensory attributes of prickly pear fruits from inter-Andean valleys to be preserved, making it a potential fruit for export and conservation due to its seasonality.


Asunto(s)
Antioxidantes , Frutas , Frutas/química , Perú , Ácido Ascórbico , Polifenoles/análisis , Vitaminas
2.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1876-1884, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-37282963

RESUMEN

To study the effects of different drying methods on the quality of male flowers of Eucommia ulmoides(MFOEU), we treated fresh MFOEU samples with drying in the shade(DS), vacuum freeze drying(VFD), high-or low-temperature hot air drying(HTHAD, LTHAD), microwave drying(MD), and vacuum drying(VD), respectively. The color, total flavonoid content, total polysaccharide content, and main active components such as geniposide, geniposidic acid, rutin, chlorogenic acid, galuteolin, pinoresinol diglucoside, and aucubin in MFOEU were taken as the evaluation indicators. The quality of MFOEU was comprehensively evaluated by entropy weight method combined with color index method, partial least squares discriminant analysis and content clustering heat map. The experimental results showed that VFD and DS basically kept the original color of MFOEU. The MFOEU treated with MD had higher content of total polysaccharides, phenylpropanoids, lignans, and iridoids. The MFOEU treated with LTHAD had higher content of total flavonoids and that treated with VD had lower content of active components. According to the results of comprehensive evaluation, the quality of MFOEU dried with different methods followed the order of MD>HTHAD>VFD>LTHAD>DS>VD. Considering the color of MFOEU, the suitable drying methods were DS and VFD. Considering the color, active components, and economic benefits of MFOEU, MD was the suitable drying method. The results of this study are of a reference value for the determination of suitable methods for MFOEU processing in the producing areas.


Asunto(s)
Eucommiaceae , Eucommiaceae/química , Flores/química , Flavonoides/análisis , Rutina/análisis , Ácido Clorogénico/análisis
3.
Sensors (Basel) ; 21(20)2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34695912

RESUMEN

Developments in digital image acquisition technologies and citizen science lead to more water color observations and broader public participation in environmental monitoring. However, the implications of the use of these simple water color indices for water quality assessment have not yet been fully evaluated. In this paper, we build a low-cost digital camera colorimetry setup to investigate quantitative relationships between water color indices and concentrations of optically active constituents (OACs). As proxies for colored dissolved organic matter (CDOM) and phytoplankton, humic acid and algae pigments were used to investigate the relationship between water chromaticity and concentration. We found that the concentration fits an ascending relationship with xy chromaticity values and a descending relationship with hue angle. Our investigations permitted us to increase the information content of simple water color observations, by relating them to chemical constituent concentrations in observed waters.


Asunto(s)
Colorimetría , Monitoreo del Ambiente , Color , Fitoplancton , Calidad del Agua
4.
Sensors (Basel) ; 21(10)2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-34067967

RESUMEN

In the contrary to surface oil slicks, dispersed oil pollution is not yet detected or monitored on regular basis. The possible range of changes of the local optical properties of seawater caused by the occurrence of dispersed oil, as well as the dependencies of changes on various physical and environmental factors, can be estimated using simulation techniques. Two models were combined to examine the influence of oceanic water type on the visibility of dispersed oil: the Monte Carlo radiative transfer model and the Lorenz-Mie model for spherical oil droplets suspended in seawater. Remote sensing reflectance, Rrs, was compared for natural ocean water models representing oligotrophic, mesotrophic and eutrophic environments (characterized by chlorophyll-a concentrations of 0.1, 1 and 10 mg/m3, respectively) and polluted by three different kinds of oils: biodiesel, lubricant oil and crude oil. We found out that dispersed oil usually increases Rrs values for all types of seawater, with the highest effect for the oligotrophic ocean. In the clearest studied waters, the absolute values of Rrs increased 2-6 times after simulated dispersed oil pollution, while Rrs band ratios routinely applied in bio-optical models decreased up to 80%. The color index, CI, was nearly double reduced by dispersed biodiesel BD and lubricant oil CL, but more than doubled by crude oil FL.


Asunto(s)
Contaminación por Petróleo , Algoritmos , Clorofila/análisis , Monitoreo del Ambiente , Océanos y Mares , Tecnología de Sensores Remotos
5.
J Sci Food Agric ; 97(7): 2147-2153, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27594557

RESUMEN

BACKGROUND: Salted Sun-dried meat is a traditional process of meat salting that can improve quality and overall acceptance. The present study compared the physicochemical and sensory attributes of fresh and salted sun-dried meat from Nellore Zebu (Bos taurus indicus) bulls (n = 32) and evaluated diets containing different levels (0%, 7%, 14% and 21%) of licury cake in diets provided to Nellore finished in a feedlot. RESULTS: Salted sun-dried meat decreased moisture (P < 0.0001) and ether extract (P = 0.0002) contents but increased ash (P < 0.0001) and protein (P < 0.0001) contents compared to fresh meat. The addition of licury resulted in linear increases in moisture (P = 0.02) and quadratic effects on Warner-Bratzler shear force (P < 0.03) in fresh meat. Cooking weight loss (P < 0.0001) and Warner-Bratzler shear force (P = 0.03) were reduced by the manufacturing process of sun-dried meat. Sun-dried meat presented greater color index L* (P = 0.0032), a* (P < 0.0001) and c* (P < 0.0001) values but a lower index color b* (P < 0.0001) value compared to fresh meat. Salted sun-dried meat presented greater sensory characteristic scores compared to fresh meat (P > 0.05). CONCLUSION: Licury cake can be used in 21% of dry matter in diets to finish animals in feedlot without lessening the quality fresh meat or sundried meat. Salted sun-dried meat presented a greater overall acceptance. © 2016 Society of Chemical Industry.


Asunto(s)
Alimentación Animal/análisis , Bovinos/metabolismo , Productos de la Carne/análisis , Animales , Fenómenos Biomecánicos , Bovinos/crecimiento & desarrollo , Manipulación de Alimentos , Preferencias Alimentarias , Humanos , Masculino , Carne/análisis , Músculo Esquelético/química , Cloruro de Sodio , Gusto
6.
Sensors (Basel) ; 16(6)2016 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-27322264

RESUMEN

This article proposes a novel method for detecting forest fires, through the use of a new color index, called the Forest Fire Detection Index (FFDI), developed by the authors. The index is based on methods for vegetation classification and has been adapted to detect the tonalities of flames and smoke; the latter could be included adaptively into the Regions of Interest (RoIs) with the help of a variable factor. Multiple tests have been performed upon database imagery and present promising results: a detection precision of 96.82% has been achieved for image sizes of 960 × 540 pixels at a processing time of 0.0447 seconds. This achievement would lead to a performance of 22 f/s, for smaller images, while up to 54 f/s could be reached by maintaining a similar detection precision. Additional tests have been performed on fires in their early stages, achieving a precision rate of p = 96.62%. The method could be used in real-time in Unmanned Aerial Systems (UASs), with the aim of monitoring a wider area than through fixed surveillance systems. Thus, it would result in more cost-effective outcomes than conventional systems implemented in helicopters or satellites. UASs could also reach inaccessible locations without jeopardizing people's safety. On-going work includes implementation into a commercially available drone.

7.
Food Chem ; 461: 140894, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39163722

RESUMEN

Fruit maturity at harvest is a major factor in determining its quality. In this study, external skin color of grape has been utilized to predict their chemical content and, in turn, the maturity of the fruit. Measurements of the chemical content such as Brix and acidity were made on ten bunches of "Shine Muscat" grapes at three different harvest periods (immature, mature, and overmature). Using a machine vision system, color and UV-excited fluorescence images of grape berries and bunches were taken during the respective harvest stages. Acquired images were processed using ImageJ to obtain RGB values. Rratio and a*/b* are strongly related to Brix and sugar-to-acid ratio of grape fruit, with regression coefficients of 0.5626 and 0.5180, repectively. It was found that a* color index was the best predictor of grape bunch maturity. Furthermore, discriminant analysis has shown that color images of grape berries perform better than 365 nm fluorescence images.

8.
Polymers (Basel) ; 16(13)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-39000633

RESUMEN

Aqueous suspensions rely on electrostatic interactions among suspended solids, posing a significant challenge to maintaining stability during storage, particularly in the food and pharmaceutical industries, where synthetic stabilizers are commonly employed. However, there is a growing interest in exploring new materials derived from natural and environmentally friendly sources. This study aimed to optimize the stability parameters of a novel Altoandino Nostoc Sphaericum hydrocolloid (NSH) extracted via micro atomization. Suspensions were prepared by varying the pH, gelatinization temperature and NSH dosage using a 23 factorial arrangement, resulting in eight treatments stored under non-controlled conditions for 20 days. Stability was assessed through turbidity, sedimentation (as sediment transmittance), ζ potential, particle size, color and UV-Vis scanning. Optimization of parameters was conducted using empirical equations, with evaluation based on the correlation coefficient (R2), average relative error (ARE) and X2. The suspensions exhibited high stability throughout the storage period, with optimized control parameters identified at a pH of 4.5, gelatinization temperature of 84.55 °C and NSH dosage of 0.08 g/L. Simulated values included turbidity (99.00%), sedimentation (72.34%), ζ potential (-25.64 mV), particle size (300.00 nm) and color index (-2.00), with simulated results aligning with practical application. These findings suggest the potential use of NSH as a substitute for commercial hydrocolloids, albeit with consideration for color limitations that require further investigation.

9.
Poult Sci ; 102(11): 103052, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37734360

RESUMEN

The BG line, originated by crossing 2 Chinese indigenous breeds, Dongxiang blue eggshell and Jiangshan black-bone, has been bred for black carcass and blue-greenish eggs. Aiming to study the genetic parameters and selection aspects of these eggshell colors, the 4 colorimeter parameters (L*, a*, b*, SCI = L*-a*-b*) were measured on ∼5 eggs/hen/age (200 d and 300 d) from each hen in 3 generations (G4 = 452, G5 = 508, G6 = 498). Visual eggshell color was classified as either "Light," "Blue," "Green," or "Olive," and data from G4 and G5 indicated that visual eggshell color was more accurately determined by combining the classifications of single representative egg/hen by 4 independent observers. Based on the apparent gradual variation in visual color, the 4 colors were expressed numerically (Light = 1, Blue = 2, Green = 3, Olive = 4) and the averages of the 4 observers (AveObs) were used as quantitative expression of the visual color of each egg. This expression, in the range from Blue to Olive, was highly significantly correlated with L*, b* and SCI. The a* values were also associated with AveObs, but not linearly; AveObs between 2 (Blue) and 3 (Green) had lowest a*, and it increased as AveObs was more Light (<2) or more Olive (>3). The heritability estimates of the colorimeter parameters were mostly very high; those of b* and SCI ranged between 0.7 and 0.8, and those of L* and a* between 0.6 and 0.7, indicating that they can serve as criterions to select for blue and/or green eggshells. The phenotypic and genetic correlations between the colorimeter parameters were highly significant and favorable. It is suggested that effective breeding for blue eggs can be done by selecting hens laying eggs with highest SCI/L* or lowest b* (against green and olive shades), followed by selection for low a* (against light shades). Breeding for green eggs can be done by selecting hens laying eggs with SCI ≈ 75 and/or L* ≈ 80 and/or b* ≈ 12. Breeding for hens that lay either blue or green eggs can be done by selection for low a* values.

10.
Plant Methods ; 17(1): 104, 2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34641927

RESUMEN

BACKGROUND: Forest canopies are highly sensitive to their growth, health, and climate change. The study aims to obtain time sequence images in mix foresters using a near-earth remote sensing method to track the seasonal variation in the color index and select the optimal color index. Three different regions of interest (RIOs) were defined and six color indexes (GRVI, HUE, GGR, RCC, GCC, and GEI) were calculated to analyze the microenvironment difference. The key phenological phase was identified using the double logistic model and the derivative method, and the phenology forecast of color indexes was performed based on the long short-term memory (LSTM) model. RESULTS: The results showed that the same color index in different RIOs and different color indexes in the same RIO present a slight difference in the days of growth and the days corresponding to the peak value, exhibiting different phenological phases; the mean squared error (MSE), root mean squared error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) of the LSTM model was 0.0016, 0.0405, 0.0334, and 12.55%, respectively, indicating that this model has a good forecast effect. CONCLUSIONS: In different areas of the same forest, differences in the micro-ecological environment in the canopies were prevalent, with their internal growth mechanism being affected by different cultivation ways and the external environment. Besides, the optimal color index also varies with species in phenological response, that is, different color indexes are used for different forests. With the data of color indexes as the training set and forecast set, the feasibility of the LSTM model in phenology forecast is verified.

11.
Huan Jing Ke Xue ; 42(5): 2213-2222, 2021 May 08.
Artículo en Zh | MEDLINE | ID: mdl-33884790

RESUMEN

Urban water is a significant part of the urban ecosystem. Therefore, a comprehensive evaluation method of the water environment was proposed based on domestic high-resolution images. The relationships between the spectral characteristics and water quality parameters of urban water were analyzed based on sampling in Nanjing, Wuxi, Changzhou, and Yangzhou from 2017 to 2019. An index named the U-FUI (urban Forel-Ule index) suitable for urban water based on GF-2 images was proposed to achieve the classification of urban water on the basis of the international standard chroma conversion model and the Forel-Ule index. Independent verification data showed that the recognition accuracy of the classification model could reach 72%. The results indicated that urban water can be classified into six classes from Ⅰ to Ⅵ, which represent water colors of blue, light green, dark green, yellow, yellowish brown, and dark grey, respectively, according to the U-FUI. Among them, the water quality of U-FUI Ⅰ water is good, but is rarely distributed in urban water. The concentrations of chlorophyll-a in U-FUI Ⅱ-Ⅲ water are higher than those of the other classes; the concentrations of total suspended solids, particularly inorganic suspended solids, of U-FUI Ⅳ-Ⅴ water are higher than those of the other classes; and the water quality of U-FUI Ⅵ water is poor and the water quality parameters are different from those of the other classes. Meanwhile, the method was successfully applied to the GF-2 image of Nanjing on April 9, 2018. The results showed that the urban water in Nanjing is mainly composed of U-FUI Ⅱ-Ⅳ water, whereas the distribution of U-FUI Ⅰ, Ⅴ, and Ⅵ water is lower in the city. The spatial distribution characteristics were consistent with the results of in-situ sampling in the same period.

12.
Foods ; 9(1)2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31963170

RESUMEN

Color index and water content are important indicators for evaluating the quality of fresh-cut potato tuber slices. In this study, hyperspectral imaging combined with multivariate analysis was used to detect the color parameters (L*, a*, b*, Browning index (BI), L*/b*) and water content of fresh-cut potato tuber slices. The successive projections algorithm (SPA) and competitive adaptive reweighted sampling (CARS) were used to extract characteristic wavelengths, partial least squares (PLS) and least squares support vector machine (LS-SVM) were utilized to establish regression models. For color prediction, R2c, R2p and RPD of all the LSSVM models established for the five color indicators L*, a*, b*, BI, L*/b* were exceeding 0.90, 0.84 and 2.1, respectively. For water content prediction, R2c, R2p, and RPD of the LSSVM models were over 0.80, 0.77 and 1.9, respectively. LS-SVM model based on full spectra was used to reappear the spatial distribution of color and water content in fresh-cut potato tuber slices by pseudo-color imaging since it performed best in most cases. The results illustrated that hyperspectral imaging could be an effective method for color and water content prediction, which could provide solid theoretical basis for subsequent grading and processing of fresh-cut potato tuber slices.

13.
J Food Sci ; 83(5): 1366-1372, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29660800

RESUMEN

This study was conducted to test the effect of dietary tannin on the fatty acid profile and sensory attributes of meat from Nellore steers. Thirty-two Nellore bull male were distributed in a completely randomized design and fed diets with condensed tannin extract as follows: 0, 10, 30, and 50 g/kg total DM basis. The physicochemical composition of the meat, lipid oxidation, fatty acid profile, flavor, tenderness, and overall acceptance were evaluated. There was a linear decrease (P ≤ 0.05) on lipid content, tenderness, cooking weight loss, myristic, palmitic, and oleic acids in meat as tannin increased in the diets. The total saturated and monounsaturated fatty acids, the atherogenicity index decreased. However, a linear increase (P ≤ 0.05) was observed for linoleic, linolenic, arachidonic, eicosapentaenoic, and docosapentaenoic acids. The physicochemical characteristic of the meat, such as moisture, ash, and protein contents, water retention capacity, final pH, Warner-Bratzler shear force, collagen, and color indexes (lightness, redness, yellowness, and chrome) did not change with dietary tannin. Also, CLA, n-6:n-3 ratio, Δ9 -desaturase, and elongase activity were not different among diets. In conclusion, condensed tannin linearly increases unsaturated fatty acids and decreases the atherogenicity index of meat; thus, it can be recommended at the highest level (50 g/kg DM) in the diet of Nellore steers. PRACTICAL APPLICATION: Agriculture byproducts plays an important part in the diet of ruminant animals and consequently on food chain and has implications for the composition and quality of the livestock products (milk, meat, and eggs) that people consume. Feeding tannin to steers increases the amount of unsaturated fatty acids and meat tenderness, with a concomitant reduction on saturated fatty acids and the atherogenicity index in meat. Thus, we recommend adding tannin to steer diets to reduce the risk factors for cardiovascular diseases in red meat for human consumption.


Asunto(s)
Fenómenos Químicos , Ácidos Grasos/análisis , Proantocianidinas/administración & dosificación , Carne Roja/análisis , Adulto , Alimentación Animal/análisis , Animales , Bovinos , Color , Comportamiento del Consumidor , Productos Lácteos/análisis , Dieta/veterinaria , Femenino , Análisis de los Alimentos , Calidad de los Alimentos , Inocuidad de los Alimentos , Humanos , Masculino , Persona de Mediana Edad , Proantocianidinas/análisis , Factores de Riesgo , Gusto , Adulto Joven
14.
Front Plant Sci ; 9: 363, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29681907

RESUMEN

Color and other quality parameters of "Redglobe" grape (Vitis vinifera L.) berries were evaluated after treatment with brassinosteroid (BR) analogs. Three BRs analogs (24-epibrassinolide, Triol, or Lactone) were applied at three concentrations (0.0, 0.4, or 0.8 mg⋅L-1), at the onset of veraison. A commercial formulation (B-2000®) was also applied, at a recommended rate of 0.06 mg⋅L-1. The tested BR analogs were effective improving berry color (evaluated as color index for red grapes, CIRG), increasing the levels of soluble solids and anthocyanins, and changing the types of anthocyanins present without altering other quality and yield parameters. The effects of BR analogs on color enhancement could be explained by an increase in soluble solids content and/or anthocyanin content. Treatment with 24-epibrassinolide (at 0.4 mg⋅L-1) or the commercial formulation tended to favor the production of dihydroxylated anthocyanins, which are responsible for the red and pink colors of grape berries. Results indicate that the use of BRs constitutes a potential tool in the production of table grapes. This is the first report of this enhancement effect in a productive context.

15.
Phytochemistry ; 95: 109-17, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23962802

RESUMEN

The transcription factor ZAT12 is a member of stress-responsive C2H2 type zinc finger protein (ZFP) reported to control the expression of stress-activated genes mediated via ROS in plants. BcZAT12-transformed tomato cv. H-86, var. Kashi vishesh (lines ZT1-ZT6) over-expressing the gene product is demonstrated herein to be tolerant to heat-shock (HS)-induced oxidative stress. Results reveal that the relative expression of ZAT12 as well as heat induced Hsp17.4 and Hsp21 gene transcripts increased in transgenic upon exposure to HS. The transformed tomato lines ZT1 and ZT5 had significantly lowered free radical formation, improved electrolyte leakage, relative water content and chlorophyll levels with an enhanced activities of antioxidant enzymes viz. superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase when exposed to HS. HS-induced oxidative stress by over-expression of the BcZAT12 gene transcripts in tomato as well as by largely enhancing the ROS-scavenging capacity and up regulation of Hsp transcripts. This enables the transgenic tomato plants to acquire a greater ability to counteract HS-induced oxidative stress, being endowed with more reduced antioxidant pools. The use of these HS-tolerant tomato lines could possibly be used for tomato cultivation in the areas affected by sudden temperature changes.


Asunto(s)
Adaptación Fisiológica/genética , Antioxidantes/metabolismo , Sequías , Calor , Estrés Oxidativo/genética , Solanum lycopersicum/genética , Factores de Transcripción/genética , Clorofila/metabolismo , Electrólitos/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Solanum lycopersicum/enzimología , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/metabolismo , Transformación Genética , Regulación hacia Arriba , Agua/metabolismo
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