INSTRUMENTAL AND SENSORY TEXTURAL PROPERTIES OF FURA

ABSTRACT

A uniaxial compression test and sensory textural analysis was conducted of fura samples made from millet flour. Significant differences (p<0.05) existed among the samples for hardness (the force to compress the sample between molar teeth), cohesiveness (extent to which sample falls apart during chewing) and gumminess (denseness and cohesion persisting during mastication). Correlations between sensory and instrumental tests revealed that a significant relationship exists between modulus of deformability and cohesiveness (r=?0.93, p<0.05); gradient and springiness (r=?0.90, p<0.05); deformation at failure and chewiness (r=0.98, p<0.05); energy per unit mass and gumminess (r=?0.95, p<0.05). A fura quality scale was established based on the peak force; soft and poor quality fura have a peak force of <19 kN; acceptable fura has a peak force of 19–24 kN; a firm and good quality fura, 24–25 kN; very hard and very poor quality fura have a peak force of >25 kN.     

SENSORY AND CHEMICAL EVALUATION OF MANCHEGO CHEESE AND OTHER CHEESE VARIETIES AVAILABLE IN THE SPANISH MARKET

Chemical and sensory characteristics of 28 different cheeses acquired in the Spanish market were evaluated. Principal Component Analysis (PCA) of the physico‐chemical results showed that the cheeses were separated into three groups: hard, soft and elastic cheeses, while PCA of the sensory results classified the same cheeses into four groups, distinguishing between two types of hard cheese (Manchego cheese with Appellation of Origin and other Spanish hard cheeses). Sensory Analysis differentiated between cheeses of very similar physicochemical characteristics, the attributes that contributed most to differentiation being fragility, adhesiveness, pasty and spicy. Some correlations were obtained between sensorial and chemical variables, the most significant being hardness versus total nitrogen (TN) and versus dry matter (DM), and fragility versus water activity.     

冰淇淋的感官评定方法与感官质量控制

介绍冰淇淋的感官评定要素,包括:建立感官实验室、培训感官品评员、选择感官品评方法,并阐述冰淇淋的感官质量控制方法.     

EFFECTS OF CHITOOLIGOSACCHARIDE ON THE PHYSICOCHEMICAL, TEXTURAL AND SENSORY PROPERTIES OF TOFU

Chitinous polymers have been experimented with for the purpose of shelf-life extension of foods due to their antimicrobial activity. Food additives, however, may impair the taste, color or texture of foods. Therefore, it is necessary to evaluate the effect of a food additive on foods before it is used. In this study, we investigated how the physicochemical properties, microstructure, textural properties and sensory characteristics of tofu are affected by the addition of chitooligosaccharide during its preparation. The addition of chitooligosaccharide to tofu did not significantly affect its physicochemical properties including moisture content, yield, turbidity and color. The chitooligosaccharide tofu, however, had lower hardness and smaller protein aggregates than the control tofu. The chitooligosaccharide did not influence most sensory attributes of tofu except for imparting a bitter taste.     

THE SENSE OF SMELL IN FOOD QUALITY AND SENSORY EVALUATION

The sense of smell is the major contributing sensory system in the perception of food aromas and volatile flavors. Illustrations of the importance of olfactory sensations can be found in the literature on product quality defects and in the importance of aroma andflavor characteristics in driving consumer acceptability of foods. Assessing olfactory-mediated characteristics of flavors is challenging, however, for a number of reasons. There are wide individual differences in olfactory acuity, as suggested by the existence of specific anosmias. Panelists are often strongly influenced by the immediate context in which samples are judged. Developing a useful consensual language to describe smells in sensory analyses can also be difficult. In spite of these challenges, the human sense of smell is the ultimate discriminator of food aroma and flavor quality; instrumental analyses are a poor substitute. Even in cases in which chemical components of food flavors have been identified, these must be cross-referenced against human sensitivities in order to estimate their sensory impact.     

EVALUATION OF INSTRUMENTAL METHODS FOR FIRMNESS MEASUREMENT OF FRESH AND CANNED CLINGSTONE PEACHES

The firmness of fresh and canned clingstone peaches was investigated using blade extrusion, back extrusion, and shear-compression instruments. The three techniques yielded results which correlated well among themselves and to sensory evaluation of peach firmness. Results indicate that high vacuum flame sterilization yields a canned product which is closer in firmness to fresh peaches than is the conventionally retorted product.     

INTERDEPENDENCY AND UNDERLYING DIMENSIONS OF SENSORY TEXTURAL CHARACTERISTICS OF SELECTED FOODS2

Sensory texture profile data for butters, cheeses, fish gels, frankfurters, peanut butters, raw potatoes, and baked sweet potatoes were subjected to principal component analysis to study the interdependence and the underlying dimensions of the sensory textural characteristics. The results indicated that the character notes used by the panel to describe the texture profile of each product were not entirely independent but formed a pattern of interdependency in the underlying dimensional structure. The texture profile could be described by about ½ the orthogonal factors (underlying dimensions) compared to the original character notes and still explain about 72% of the original variance. It is concluded that the texture profile analysis for each of the products in this study could be simplified by reducing the character notes being evaluated.     

TEXTURE MODIFYING AGENT AND BINDER EFFECTS ON THE YIELD,SENSORY AND TEXTURAL PROPERTIES OF BONELESS HAMS1

To test their binding characteristics, 11 texture modifying agents/binders were added to cure formulations under industry conditions. Ham muscles were excised, butterflied, denuded of fat, tenderized, cured at 158% of raw weight, massaged, stuffed, and cooked/smoked overnight. The yield of cooked and smoked ham, shrinkage during chilling after cooking, and yield of ready-to-ship ham were not affected (P > 0.05) by binder. Integrated Ingredients Zyest 90 whey and yeast produced lower L * values than Protein Technology HVF 51. A. E. Staley Consista Starch and Integrated Ingredients Zyest 90 whey and yeast produced higher a* values than Hercules M8 78F and Protein Technology HVF 51. Protein Technology HVF 51 produced higher b* values than Hercules M8 78 F, DMV EM 25, and National Firmtex. AMP 80 produced a lower shear force value than DMV EM 25. The control and Hercules M8 78F produced higher moisture percentages than A. E. Staley Low Temp 452 and DMV EM 25. Protein Technology Supro 595 produced superior overall and cooked/smoked yields while A. E. Staley Consista Starch produced inferior overall and cooked/smoked yields.     

PREDICTION OF INSTRUMENTAL AND SENSORY TEXTURAL CHARACTERISTICS OF MAHON CHEESE FROM ULTRASONIC MEASUREMENTS

Ultrasonic velocity was related to sensory and instrumental texture measurements. A semi-logarithmic model (Weber-Fechner) was used to relate the sensory and instrumental texture measurements. The ultrasonic velocity ranged from 1650 to 1723 m/s for the softest and hardest cheese, respectively. As expected from theoretical equations, the ultrasonic velocity was related to the square root of the instrumental measurements. The deformability modulus (r²=0.93) and the slope in puncture (r²=0.85) were the most closely related parameters. A model developed from the relationship between sensory and instrumental texture and the relationship between ultrasonic velocity and instrumental texture, was used to relate velocity to sensory measurements. Elasticity (r²= 0.84) and firmness (r²= 0.81) were the sensory attributes which best correlated with ultrasonic velocity. From the obtained results, it was concluded that ultrasonic velocity measurements could be used to assess instrumental and sensory properties of Mahon cheese texture nondestructively, and therefore could be used for grading purposes.