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Texture Parameters (texture + parameter)
Selected AbstractsNuclear morphometry and texture analysis of B-cell non-Hodgkin lymphoma: Utility in subclassification on cytosmearsDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2010Shilpa Gupta M.D. Abstract Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid neoplasms and accurate subclassification is an essential prerequisite for proper management of patients. This study was aimed at evaluating the utility of nuclear morphometry and textural features on cytology smears to classify the cases of NHL on aspiration cytology. Fine needle aspiration smears of 50 cases of B-cell NHL were included. Various morphometric and texture parameters were obtained by manually tracing the nuclei on digitized images in each case and discriminant analysis performed using various features taken individually as well as all together. The percentage of cells correctly classified to a particular NHL subtype using the discriminant functions so obtained was noted. Our results show that discriminant analysis done on size parameters could correctly classify a greater number of cells than on shape parameters (36.4% vs. 21.2%, respectively). Texture parameters based on single pixel values (first order texture) were inferior (42.8%) to those based on pair of pixels (58.7%) in subtyping of cells. Discriminant analysis based on color parameters was more effective (61.9%) as compared to rest of the morphometric and textural parameters. Using all the morphometric and textural parameters together, 83.3% of cells could be correctly classified to a particular NHL subtype. The present study, perhaps the first study of detailed morphometric analysis on cytosmears, shows that satisfactory classification of NHL on aspiration cytology is possible using nuclear morphometry and textural parameters considered together. These results are promising for further studies on this subject and development of automated cytodiagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source] KINETICS of QUALITY CHANGE DURING COOKING and FRYING of POTATOES: PART I. TEXTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2003F. NOURIAN ABSTRACT Kinetics of texture change during cooking and frying of potatoes were evaluated in this study. Potatoes were cut into cylinders (diameter × height: 20 mm × 20 mm for cooking, and 10 mm × 20 mm for frying) and cooked in a temperature controlled water bath at 80,100C or fried in a commercial fryer at 160,190C for selected times. the cooked samples were water cooled while the fried samples were air cooled immediately after the treatment. Test samples were then subjected to a single cycle compression test in a computer interfaced Universal Testing Machine and three textural properties (hardness, stiffness and firmness) were derived from the resulting force-deformation curves. Texture parameters of cooked potatoes decreased with progress of cooking time and the rate of texture changes associated with each temperature was found to be consistent with two pseudo first-order kinetic mechanisms, one more rapid than the other. Textural values of fried potatoes were found to increase with frying time and also followed a first order kinetic model. Temperature sensitivity of rate constants was adequately described by Arrhenius and z-value models. [source] Nuclear morphometry and texture analysis of B-cell non-Hodgkin lymphoma: Utility in subclassification on cytosmearsDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2010Shilpa Gupta M.D. Abstract Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid neoplasms and accurate subclassification is an essential prerequisite for proper management of patients. This study was aimed at evaluating the utility of nuclear morphometry and textural features on cytology smears to classify the cases of NHL on aspiration cytology. Fine needle aspiration smears of 50 cases of B-cell NHL were included. Various morphometric and texture parameters were obtained by manually tracing the nuclei on digitized images in each case and discriminant analysis performed using various features taken individually as well as all together. The percentage of cells correctly classified to a particular NHL subtype using the discriminant functions so obtained was noted. Our results show that discriminant analysis done on size parameters could correctly classify a greater number of cells than on shape parameters (36.4% vs. 21.2%, respectively). Texture parameters based on single pixel values (first order texture) were inferior (42.8%) to those based on pair of pixels (58.7%) in subtyping of cells. Discriminant analysis based on color parameters was more effective (61.9%) as compared to rest of the morphometric and textural parameters. Using all the morphometric and textural parameters together, 83.3% of cells could be correctly classified to a particular NHL subtype. The present study, perhaps the first study of detailed morphometric analysis on cytosmears, shows that satisfactory classification of NHL on aspiration cytology is possible using nuclear morphometry and textural parameters considered together. These results are promising for further studies on this subject and development of automated cytodiagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source] PECAN TEXTURE AS AFFECTED BY MOISTURE CONTENT BEFORE FREEZING AND THAWING RATEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2001B.B. SURJADINATA ABSTRACT The texture of pecans was determined as affected by initial moisture content before freezing (3 vs 5%), thawing rate (IX, 1.2X, 2.7X, 5.6X), and multiple freeze-thaw cycles (0, 1X, 3X, 6X, 9X, 12X). Texture was determined by instrumental Texture Profile Analysis (TPA) and sensory evaluation. Initial moisture content before freezing had a significant effect on all of the sensory evaluation parameters (hardness, fracturability, cohesiveness, and denseness) and most of the instrumental TPA texture parameters (hardness, fracturability, springiness, resilience, and chewiness). Thawing rate only affected TPA hardness and resilience. TPA fracturability correlated best with sensory fracturability. The sensory panel could not detect any differences between the different thawing rates. The slowest thawing rate affected more parameters than the medium and faster rates. More freeze/thaw cycles significantly decreased most TPA texture values, especially for pecans at higher moisture content. [source] PREDICTION OF TEXTURE IN GREEN ASPARAGUS BY NEAR INFRARED SPECTROSCOPY (NIRS)JOURNAL OF FOOD QUALITY, Issue 4 2002D. PEREZ NIR spectroscopy was used to estimate three textural parameters of green asparagus: maximum cutting force, energy and toughness. An Instron 1140 Texturometer provided reference data. A total of 199 samples from two asparagus varieties (Taxara and UC-157) were used to obtain the calibration models between the reference data and the NIR spectral data. Standard errors of cross validation (SECV) and r2 were (5.73, 0.84) for maximum cutting force, (0.58, 0.66) for toughness, and (0.04, 0.85) for cutting energy. The mathematical models developed as calibration models were tested using independent validation samples (n =20); the resulting standard errors of prediction (SEP) and r2 for the same parameters were (6.73, 0.82), (0.61, 0.57) and (0.04, 0.89), respectively. For toughness, substantially improved r2 (0.85) and SEP (0.36) when four samples exhibiting large residual values were removed. The results indicated that NIRS could accurately predict texture parameters of green asparagus. [source] Flaxseed in Breadmaking: Effects on Sensory Quality, Aging, and Composition of Bakery ProductsJOURNAL OF FOOD SCIENCE, Issue 4 2006Terhi A. Pohjanheimo ABSTRACT:, This paper describes the effect of flaxseed on two bread formulations. The quality of bread rolls,containing flaxseed,and the quality of cinnamon rolls,containing flaxseed and flaxseed oil,is determined by sensory evaluation (texture, odor, and flavor), instrumental texture measurement and chemical analysis (fatty acids, fiber, secoisolarisiresinol diglycoside, and cadmium). Bread aging is monitored by measuring sensory attributes during storage. The results indicate that the flaxseed rolls retain moisture and softness more efficiently than the control rolls that do not contain flaxseed. No off-odors were detected during the storage period from 0 to 6 d at room temperature (+22 °C), although flaxseed rolls and cinnamon rolls were discovered to be high in unsaturated fats. The major fatty acid in both bakery samples that contained flaxseed was ,-linolenic acid. The flaxseed rolls were also high in fiber. Therefore, from a nutritional viewpoint flaxseed shows beneficial properties in breadmaking. It has a positive impact on the texture parameters during storage as well as on the nutritional composition, for example, the content of fiber and unsaturated fats. [source] MODELING OF TEXTURE EVOLUTION OF CAKES DURING STORAGEJOURNAL OF TEXTURE STUDIES, Issue 1 2010MANUEL GÓMEZ ABSTRACT The aim of this work is to model the variation of texture parameters in cakes during staling. The evolution was studied in layer cakes (cake A) and sponge cakes (cake B). The effect of storage temperature and the addition of fiber, xanthan gum (cake A) and emulsifier (cake B) were also studied. The best model to adjust the texture parameters variation during storage in both kinds of cakes was square root x (y = a + b * x1/2), except for firmness and springiness in cakes B. Firmness and springiness were adjusted the best to the linear model. In the model, y stood for the textural parameters and x for the time. a and b were related to the initial value of the studied parameter and with its change over time respectively. In both kinds of cakes, A and B, the firmness and gumminess increased, and the cohesiveness, springiness and resilience decreased, as the storage time increased. The increase in the storage temperature and the addition of fiber minimized the firmness changes in both kinds of cakes. PRACTICAL APPLICATIONS This methodology simplifies the study of cake textural parameters during storage and the result interpretation. Moreover, the correlation analysis has demonstrated that the number of textural parameters of cakes to study can be reduced. [source] STANDARD SCALES FOR CRISPNESS, CRACKLINESS AND CRUNCHINESS IN DRY AND WET FOODS: RELATIONSHIP WITH ACOUSTICAL DETERMINATIONSJOURNAL OF TEXTURE STUDIES, Issue 4 2008MAITE A. CHAUVIN ABSTRACT A trained panel developed rating scales for crispness, crunchiness and crackliness for dry and wet foods based on the auditory perception of selected foods. The newly developed scales were then evaluated by 40 untrained panelists and the sound perception of standard foods was assessed through the analysis of the root mean square (RMS) of the 5-s audio waveforms and multidimensional scaling (MDS). The RMS was highly correlated to auditory sensory perception of crispness (r = 0.83 and 0.96), crunchiness (r = 0.99 and 0.99) and crackliness (r = 0.88 and 0.96) for dry and wet foods, respectively. MDS technique applied for the 40 untrained panelists was instructive in assessing auditory textural differences of naďve panelists and a useful statistical instrument to graphically validate selected scales. Auditory perception of the selected foods were rated similarly using standard auditory texture scales for crispness, crunchiness and crackliness developed by the trained panel (oral evaluation) and MDS results from the untrained panel (recordings). PRACTICAL APPLICATIONS Crispness, crunchiness and crackliness are not only important and useful descriptors of food texture, but are also desirable textural qualities in many foods. The lack of consistency in the procedures used for the evaluation of crunchy, crispy and crackly in sensory studies often results in confusion when training expert panels. Research will benefit textural studies through an improvement of consistent textural definitions and development of standard scales and evaluation techniques. The crispness, crunchiness and crackliness scales developed and applied in the current study represent a new potential standard frame of reference that may be used for training panelists in texture parameters related to food auditory perception. The scales may be considered illustrations demonstrating full and practical ranges for each texture attribute with regard to analyzing auditory parameters of foods and effective objective tools for assessing panelists in descriptive analysis. [source] RELATIONSHIPS BETWEEN SENSORY AND RHEOLOGICAL MEASUREMENTS OF TEXTURE IN MATURING COMMERCIAL CHEDDAR CHEESE OVER A RANGE OF MOISTURE AND pH AT THE POINT OF MANUFACTUREJOURNAL OF TEXTURE STUDIES, Issue 4 2006C.D. EVERARD ABSTRACTS Textural characteristics of 10 Cheddar cheeses with a range of moisture contents and pH values were investigated by sensory and instrumental methods, over a 9-month maturing period. A trained panel of nine assessors described the sensory texture characteristics of the cheeses using 11 texture parameters. Instrumental parameters were derived using texture profile analysis. Relationships between sensory, instrumental, compositional and maturation properties of the cheeses were determined with the aid of principal component analysis and multiple linear regression. Nine sensory parameters significantly correlated with instrumental parameters, e.g., sensory rubbery correlated with instrumental firmness (R = 0.696, P < 0.001), chewiness (R = 0.679, P < 0.001), fracture stress (R = 0.669, P < 0.001) and springiness (R = 0.643, P < 0.001). Sensory firmness corresponded closely with instrumental firmness (R = 0.539, P < 0.001) and fracture stress (R = 0.518, P < 0.001). Sensory and instrumental texture parameters were significantly affected by changes in moisture content, pH and maturation. [source] DATA ANALYSIS OF PENETROMETRIC FORCE/DISPLACEMENT CURVES FOR THE CHARACTERIZATION OF WHOLE APPLE FRUITSJOURNAL OF TEXTURE STUDIES, Issue 4 2005C. CAMPS ABSTRACT The objective of the present study was to compare two chemometric approaches for characterizing the rheological properties of fruits from puncture test force/displacement curves. The first approach (parameter approach) computed six texture parameters from the curves, which were supposed to be representative of skin hardness, fruit deformation before skin rupture, flesh firmness and mechanical work needed to penetrate the fruit. The second approach (whole curve approach) used the whole digitized curve (300 data points) in further data processing. Two experimental studies were compared: first, the variability of the rheological parameters of five apple cultivars; second, the rheological variability that was characterized as a function of storage conditions. For both approaches, factorial discriminant analysis was applied to discriminate the fruits based on the measured rheological properties. The qualitative groups in factorial discriminant analysis were either the apple cultivar or the storage conditions (days and temperatures of storage). The tests were carried out using cross-validation procedures, making it possible to compute the number of fruits correctly identified. Thus the percentage of correct identification was 92% and 87% for using the parameter and the whole curve approaches, respectively. The discrimination of storage duration was less accurate for both approaches giving about 50% correct identifications. Comparison of the percentage of correct classifications based on the whole curve and the parameter approaches showed that the six computed parameters gave a good summary of the information present in the curve. The whole curve approach showed that some additional information, not present in the six parameters, may be appropriate for a complete description of the fruit rheology. [source] EFFECT OF HEN EGG PRODUCTION AND PROTEIN COMPOSITION ON TEXTURAL PROPERTIES OF EGG ALBUMEN GELSJOURNAL OF TEXTURE STUDIES, Issue 2 2001MARIANNE HAMMERSHŘJ The effect of hen age, strain and dietary amino acid intake on the egg albumen gel textural properties was studied in two experiments by textural profile analysis (TPA) and uniaxial compression (UC) tests. In experiment 1, eggs from 4 different hen flocks were heat processed industrially. Egg rejection due to poor albumen gelling was correlated to hen age (r = 0.502), albumen dry matter (r =,0.632), gel hardness of 1st compression (r =,0.765), and gel work of 1st compression (r =,0.740) in TPA. In experiment 2 two hen strains, representing two levels of egg production, were fed diets with supplementation of L-lysine, methionine or both amino acids compared to a control diet. The lysine intake ranged from 818,1272 mg/hen/day and methionine intake from 377,575 mg/hen/day among hen groups, but without significant effect on the albumen gel texture parameters. The hen strains differed significantly in egg production (P<0.001), physical (P<0.001), chemical (P<0.05) and gel textural parameters of egg albumen (P<0.01). Hen age was essential, and correlated to the industrial egg rejection (r = 0.729), albumen dry matter (r =,0.902) and gel stress at fracture (r =,0.884). Albumen gels with high fracture stress values were found to contain a modified form of ovofransferrin. [source] | ||||||||||