COMPARISON OF ATTRIBUTE LIKING AND JAR SCALES TO EVALUATE THE ADEQUACY OF SENSORY ATTRIBUTES OF MILK DESSERTS

Just-about-right (JAR) scales and attribute liking questions are usually used to study consumer perception of the sensory characteristics of food products. The aim of the present work was to compare the performance of attribute liking and JAR scales to evaluate consumers' perceived adequacy of flavor and texture of milk puddings. Two groups of consumers were asked to evaluate eight milk desserts using (1) overall liking followed by attribute liking for texture and flavor and (2) overall liking followed by JAR scales for thickness, creaminess, sweetness and vanilla flavor. Overall liking scores were significantly different when JAR scales or attribute liking questions were considered. Texture, flavor and overall liking scores were highly correlated to each other, providing the same information. JAR scales correlated better with the intensity of sensory attributes evaluated by a trained sensory panel, being JAR percentages a reliable tool to study the adequacy of sensory attributes.

PRACTICAL APPLICATIONS

Results from the present work showed that consumers might not be able to independently evaluate their liking of different sensory attributes of a product. For this reason, the use of attribute liking questions for studying the adequacy of sensory attributes in complex products would not be recommended. JAR scales were better indicators of the adequacy of sensory attributes. Consumers were able to independently evaluate texture and flavor attributes using JAR scales. However, the influence of JAR scales on overall liking scores should be taken into account when including these scales on consumer studies.     

THE APPLICATION OF TWO FREE-CHOICE PROFILE METHODS TO INVESTIGATE THE SENSORY CHARACTERISTICS OF CHOCOLATE

The concept of free-choice profiling allows untrained assessors to participate in sensory profiling. However, it is sometimes the case that such individuals are unable to describe what they perceive when the samples are presented in the isolation of the sensory testing booths. This paper reports an experiment to compare the usual free-choice profile procedure, with a more structured approach based on Kelly's repertory grid method. Generalized Procrustes analysis was used to analyse the data. The sample configurations obtained from both approaches were very similar, as were the interpretations of the main perceptual dimensions.     

FLAVOR MODIFICATION OF MILK CHOCOLATE BY CONCHING IN A TWIN-SCREW, CO-ROTATING, CONTINUOUS MIXER

Short-time continuous conching of chocolate offers significant economic advantages over traditional long-time batch methods. High-shear continous mixers can affect conching in a matter of minutes as compared to hours for traditional systems. Milk chocolate conched in two twin-screw, co-rotating, continous mixers operating in series was compared by a variety of sensory methods to chocolate conched by a batch method. A significant difference (P < 0.05) in flavor was found between chocolates conched at 60C by the continuous and batch methods, yet there was no preference for either chocolate. Chocolate conched by the batch method (23 h at 60C) had stronger caramel flavor (P < .10) than chocolate conched continuously, but there were no significant differences (P < .10) in sweet, chocolate or milk flavor. In the continuous system, caramel flavor generally increased with conching temperature and residence time; although, at the highest temperature (95C) and the longest residence time (7.5 min) caramel flavor decreased. Increasing the temperature of continuous conching from 70 to 90C produced chocolate significantly (P < .10) more like chocolate conched in a batch system for 21.5 h at 60C.     

THE EFFECT OF INFORMATION RELATED TO FAT CONTENT AND TASTE ON CONSUMER RESPONSES TO A REDUCED-FAT FRANKFURTER AND A REDUCED-FAT CHOCOLATE BAR

The effects of product information on responses to frankfurter sausages and chocolate bars were studied by comparing sensory and hedonic ratings in two conditions: blind tasting and tasting with information present. Furthermore, the effect of information alone was investigated by having the subjects rate the expected sensory and hedonic intensities of the products on the basis of packages with different claims. Three groups of subjects were tested by giving them different information: The basic group (no added claims, n=31), the reduced-fat group (products claimed to have reduced-fat, n=29) and the flavorful group (products claimed to have full meat/chocolate flavor, n=31). Product information increased the rated pleasantness of the frankfurter in all three information groups compared to the blind ratings. The information did not affect the pleasantness of the chocolate bars. The expected attribute intensities of the frankfurters and chocolates were rated lower by the reduced-fat group than by the other groups. Overall, the effect of product information was more clearly seen in ratings of sensory attributes than in pleasantness ratings.     

SIGNIFICANCE OF THE CHEMICAL COMPOSITION OF THE SECRETING AND DRY MAMMARY GLAND TO MILK SECRETION

The results herein presented furnish exact critical evidence for one more stage in milk secretion. Cows producing up to 30 pounds of milk at one milking are shown to have the lactose equivalent of all this milk in the udder when milking commences. The average excess of lactose found in the udder after subtracting the amount necessary for the contained milk is equal to 2.1 pounds. This represents the milk retained in the udder when the cow is believed to be dry. These conclusions are further supported by the fact that no sugar is found in the udder in the quiescent state. The study of the total composition of the udder as fat, ash, nitrogen, and lactose, and of the contained milk shows that there is a large excess of fat, ash, and nitrogen in proportion to that necessary for milk formation. The excess of udder lactose over the milk lactose is much less. The lactose would therefore appear to be formed from some element in the blood, probably dextrose, only as needed for the formation of milk. The composition of the dry udder is quite different in certain respects from that of the actively secreting gland. It builds up a fat reserve of a quite different Reichert-Meissl number from that of butter-fat. It has no sugar, its ash content is reduced, and the nitrogen content is like that of the secreting gland.