Curtis R. Luckett

Congruent Sound Can Modulate Odor Pleasantness

This study aimed to determine 1) whether certain background sounds can be matched with specific odors and 2) whether the background sounds can increase pleasantness for their congruent odors. In Experiment 1, congruent sounds increased odor pleasantness, but not odor intensity, significantly more than incongruent sounds. Experiment 2 demonstrated that certain background sounds can be paired with specific odors. For example, cinnamon, clove, and orange odors were rated significantly more congruent with a Christmas carol compared with the sound of brushing teeth and/or the beach sound. The congruent sounds increased odor pleasantness significantly more than incongruent sounds. Similarly, the congruent sound-induced odor pleasantness was observed in Experiment 3. As participants judged the pair of odor and sound to be more congruent, they rated the odor significantly more pleasant. Congruent sound assisted participants in identifying and in being familiar with the odor, thereby leading to an increase in odor pleasantness. However, the congruent sound-induced odor pleasantness was not obtained in all odors. In conclusion, this study provides new empirical evidence that pleasantness ratings for odors can increase in the presence of their congruent sounds.

Application of Enzyme-Treated Corn Starches in Breakfast Cereal Coating

UNLABELLED Presently ready-to-eat cereals are coated with high levels of sugar coating to extend the bowl life. Because of health concerns of added sugar, there is a need to identify alternative coating materials. This study was designed to test the efficacy of debranched corn starches with varying amylose contents as a cereal coating. Hylon VII (70% amylose), common, and waxy corn starches were gelatinized and debranched, and then sprayed onto ready-to-eat breakfast cereal flakes. The surface morphology, milk absorption, texture, and digestibility of coated cereals were determined. A starch film with a thickness of 50 to 130 μm was observed with scanning electron microscopy on the surface of the cereals coated with Hylon VII. All starch-coated cereals had a lower milk absorption value than the uncoated and glucose-coated controls. Among starch coatings, common corn starch and Hylon VII resulted in lower milk absorption than did waxy corn starch. After soaking in milk for 3 min, the peak force and work to peak of the cereals coated with corn starches were higher than those of the glucose control and uncoated reference. The cereals coated with Hylon VII were found to have an increase in dietary fiber content. The results suggest that debranched amylose-containing corn starches could extend the bowl-life of ready-to-eat cereals. PRACTICAL APPLICATION Currently, many cereals are coated with sugar to keep them from becoming soggy in milk. However, added sugar has been linked to obesity, hyperactivity, and dental caries. This has led to the investigation of alternative coating materials. This study employed the film-forming properties of enzyme-treated corn starch to function as a coating material in breakfast cereal flakes. In addition, the enzyme-treated high amylose corn starch also increased the dietary fiber content of the cereal flakes.

Characterization of oral tactile sensitivity and masticatory performance across adulthood

Texture perception is one of the most important factors in food acceptance, yet population-wide differences in texture sensations are not well understood. The variation in texture perception across populations is thought to depend on oral tactile sensitivity and masticatory performance. To address this hypothesis, we aimed to measure tactile acuity with a battery of tests and quantitate the relationship to masticatory performance. The study was performed on 98 participants, in three age groups (20-25, 35-45, or over 62). Two main measures of oral sensitivity were performed: to assess bite force, subjects were asked to discriminate between foam samples of varying hardness. Second, to assess lingual sensitivity the subjects were asked to identify 3D printed shapes using their tongue, as well as identify confectionary letters. Additionally, masticatory performance was measured through assessing each participants ability to mix two-colored chewing gum. In general, we found that sensitivity and masticatory performance in the younger age groups was superior to that of older adults. We also found a positive linear trend between bite force sensitivity and masticatory performance with younger participants, a trend not found in older participants. We found no significant relationship between age groups for bite force sensitivity and masticatory performance, suggesting that age-related declines in bite force sensitivity are not a significant cause of altered masticatory performance. This study represents a valuable first step in showing that bite force sensitivity does not depend on age, and the minimal influence of factors such as oral sensitivity on masticatory performance. PRACTICAL APPLICATIONS: In a society that is rapidly aging, it is important to understand the subtle changes in physiology and eating behavior that are associated with aging. This study used a variety of tests oral sensitivity to better understand which aspects of oral physiology are integral for effective chewing. The information gained helps shed light on to the factors that create an effective chewing cycle. Besides moving knowledge forward, this study may help in designing food and rehabilitation programs for those with trouble chewing and swallowing, increasing their overall quality of life.

The Effects of Both Chewing Rate and Chewing Duration on Temporal Flavor Perception

IntroductionPrevious research showed that the number of chews has been shown to influence flavor perception in crispy potato chips. This study aimed to further determine how the number of chews modulates the temporal dynamics of flavor perception (i.e., flavor development) in potato chips.MethodsThe number of chews was manipulated not only by changing chewing rate (40, 80, and 120 chews/min) for a fixed swallowing time (at 25 s after the onset of the first bite; experiment 1), but also by changing the time to swallow (10, 20, and 30 s after the onset of the first bite) for a constant chewing rate (80 chews/min; experiment 2).ResultsIn experiment 1, the time-intensity (TI) analysis showed that the maximum flavor intensity (Imax) and the area under the curve (AUC) were significantly higher for the medium (80 chews/min) and fast (120 chews/min) chewing rates than for the slow (40 chews/min) chewing rate in both plain and spicy flavored chips. In experiment 2, the temporal flavor perception was altered by the interaction between the chewing duration before swallowing and the flavor type of the potato chips. More specifically, in the natural chewing rate, while the Imax and AUC of spicy flavored chips were the greatest when the bolus was swallowed after the natural chewing-duration (for 20 s), the AUC of plain flavored chips was significantly greater in the longer chewing-duration (for 30 s) than the natural chewing-duration.ConclusionsThis study supports and extends the notion that the number of chews, and corresponding parameters such as chewing rate and duration, affect temporal flavor perception in the plain and spicy flavored potato chips.ImplicationsOur findings show that flavor intensity of plain and spicy potato chips can be reduced when people chew the chips slowly and/or swallow quickly.