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Texture relationships were studied using both sensory and instrumental texture proJle analysis (TPA) techniques to evaluate twenty-one food samples from a wide variety of foods. High linear correlations were found between sensory and instrumental TPA parameters for hardness (r = 0.76) and springiness (r = 0.83). No sign@cant correlations were found between sensory and instrumental TPAparameters for cohesiveness and chewiness. Logarithmic transfonnations of data 'Corresponding author Journal of Sensory Studies 13 (1998). 77-93. All Rights Reserved. 'Copyright I998 by Food & Nutrition Press, Inc.. Trumbull. Connecticut. 77 78 J.-F. MEULLENET ETAL.. improved correlations between sensory attributes and their instrumental corollaries. The correlation between sensory hardness and the logarithm ofinstrumental hardness was improved to r=O.%. The correlation between the logarithm of both sensory and instrumental springiness was improved to r = 0.86. The correlation between the logarithms of both sensory and instrumental chewiness was improved to r = 0.54, which was signiJicant at P < 0.05.

The effects of drying conditions, final moisture content, and degree of milling on the texture of cooked rice varieties, as measured by texture profile analysis, were investigated. Instrumentally measured textural properties were not significantly (α = 0.05) affected by drying conditions, with the exception of cohesiveness. Cohesiveness was lower in rice dried at lower temperatures (18°C or ambient) than in that dried at the higher commercial temperatures. Final moisture content and degree of milling significantly (α = 0.05) affected textural property values for adhesiveness, cohesiveness, hardness, and springiness; their effects were interdependent. The effects of deep milling were more pronounced in the rice dried to 15% moisture than that dried to 12%. In general, textural property values for hardness were higher and those for cohesiveness, adhesiveness, and springiness were lower in regular‐milled rice dried to 15% moisture than in that dried to 12%. In contrast, hardness values were lower and cohesiveness, adhesiveness, and springiness values were higher in deep‐milled rice dried to 15% moisture than in that dried to 12% moisture. Deep milling resulted in rice with lower hardness values and higher cohesiveness, adhesiveness, and springiness values.

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Cereal Chem. 76(1):56-62Different cultures have different preferences for cooked rice flavor and texture characteristics. These differences provide opportunities for U.S. rice varieties to fit into global markets to meet consumer demands worldwide. It is important to assess the properties of U.S. rice varieties and determine the factors that influence their eating quality. Cooked rice texture attributes can be affected by postharvest handling practices, such as degree of milling, drying condition, and final moisture. This article reports the effects of postharvest handling parameters on the texture of cooked medium-and short-grain rice varieties grown in Arkansas (AR) and California (CA), as measured by descriptive sensory analysis. The rice samples were Bengal (AR), Koshihikari (AR), Koshihikari (CA), M-401 (AR), M-401 (CA), and M-202 (CA). The six rice varieties were regular-or deep-milled and dried under one of five drying conditions to achieve final moisture levels of 12 or 15% (n = 120). A trained sensory panel developed a lexicon of 16 sensory attributes that described cooked rice texture at different phases of evaluation, beginning with manual adhesiveness and ending with mouthfeel characteristics after swallowing. Rice varieties differed in some physicochemical and sensory properties. Significant differences (P < 0.05) in adhesive properties, such as manual and visual adhesiveness and stickiness to lips, were observed. Rice samples also differed in mouthfeel properties. Factor analysis of sensory data grouped attributes into four groups that explained 68.5% of the variation in data. Primary sensory differences were due to adhesive properties assessed in the early stages of evaluation.

Cereal Chem. 77(1):64-69Measurement of cooked rice texture attributes by sensory and instrumental methods is important because of the increased popularity of rice and rice products by globally diverse cultures. Many factors influence cooked rice texture, including cultivar, physicochemical properties, postharvest handling practices (milling degree, drying conditions, and final moisture), and cooking method. Information on the relationships between sensory, physical, and chemical characteristics will lead to better methods to quickly evaluate and predict end-use qualities, which will help to match rices with specific characteristics to populations that demand those attributes. This article reports the relationships between two modes of measuring texture attributes of rices: sensory and instrumental texture analyzers. Six medium-and short-grain rice samples differing by cultivar or growing location were dried to achieve final moisture levels of 12 or 15% and then regular-or deep-milled (n = 120). Correlations between individual sensory descriptive attributes and instrumental texture profile parameters were weak. Of only 12 significant correlations, the highest value was r = 0.624. Combined sensory and instrumental data were factor-analyzed. This analysis revealed that sensory attributes still accounted for the most variation (35.32% out of 76.55%). Sensory descriptive analysis was more sensitive to subtle changes in initial texture perception including parameters relating to stickiness and adhesiveness. The two-cycle compression test for texture profile parameters (i.e., hardness, cohesiveness, adhesiveness, gumminess, springiness, and chewiness) accounted for less variation in the data on texture differences.

The effects of various postchill deboning times on functional, color, yield, and sensory attributes of broiler breast meat were determined. Broiler breast muscles were deboned at 2, 4, 6, and 24 h postmortem, and pH, color change, cooking yield, shear force values, and sensory traits of the breast meat were recorded. Data were examined by multivariate data analysis, namely principal component analysis (PCA). Averages of 13 variables (pH, delta a*, shear force, and sensory attributes of cardboardy, wet feathers, springiness, cohesiveness, hardness, moisture release, particle size, bolus size, chewiness, and metallic aftertaste-afterfeel) decreased gradually as deboning time increased from 2 to 24 h, especially for shear values after 4 h of postmortem aging. Univariate correlation coefficients among 24 variables indicated several significant correlations. Warner-Bratzler shear force had high positive correlations with 5 sensory texture attributes (cohesiveness, hardness, particle size, bolus size, and chewiness). The parameters of pH, delta L*, delta a*, delta b*, and cooking yield were not obviously correlated with shear force values or any of the 18 sensory characteristics. PCA score plot showed no clear separation of the breast muscles deboned at different postmortem times, but it was still possible to differentiate them. The loading biplot suggested that 18 variables were effective in sample differentiation, including delta L*, shear force, cooking yield, 6 sensory flavor attributes (brothy, cardboardy, wet feathers, blood/serumy, salty, and sour), all sensory texture attributes except springiness, and all afterfeel-aftertaste properties.

Rice quality is based on chemical and physical properties affecting its appearance, flavor, and texture characteristics. Sensory quality can be assessed by a combination of descriptive sensory and physicochemical property evaluations. The purpose of the present study was to assess the potential of near‐infrared reflectance spectroscopy (NIRS) and NIRS in combination with other physicochemical measurements for the determination of sensory texture attributes in whole‐grain milled rice samples. Six rice samples representing combinations of variety and growing locations received treatments of two degrees of milling and five drying conditions to achieve final moisture levels of 12 or 15% (n = 120). Quality measurements of the cooked rice included sensory and instrumental texture analyses. Quality measurements of the uncooked rice included amylose and protein (chemical reference), whiteness, transparency, and degree of milling (appearance units of milled rice), and NIRS analyses. Partial least squares (PLS) regression was used to reveal the relationships between the different types of measurements. The sensory texture attributes: manual adhesiveness (MADHES), visual adhesiveness (VADHES), and stickiness to lips (STICKI) were related to deep‐milled samples and positively correlated to amylose, whiteness, and milling degree. The attribute roughness (ROUGH) was related to light‐milled samples and positively correlated to protein and negatively correlated to amylose. The main variation in sensory attributes was a result of amylose and protein contents of the rices. A noise‐compensation value, relative ability of prediction (RAP), was used to express the degree of prediction (1.0 = best possible prediction). NIRS gave the best prediction results for the texture attributes: MADHES, VADHES, and STICKI with an RAP of 0.57, 0.54, and 0.56, respectively. NIRS is best at predicting texture characteristics of cooked rice perceived in the visual, tactile, and initial oral phases of sensory evaluation. The calibration of NIRS plus physicochemical variables did not improve the predictability of sensory texture over NIRS alone. The prediction of sensory texture in rice by NIR needs to be further investigated on a large number of samples with different varieties, growing locations, cultivation methods, harvesting methods, and processing after harvesting.