Food Oral Processing: Conversion Of Food Structure To Textural Perception
chewing behavior; Fracture; fracture properties; fundamental mechanical parameters; human; large-deformation properties; mastication; nasal aroma; physical properties; proteins/polysaccharide mixed gels; release; rheology; sensory perception; sensory texture; time-intensity; viscoelastic model foods
Food oral processing includes all muscle activities, jaw movements, and tongue movements that contribute to preparing food for swallowing. Simultaneously, during the transformation of food structure to a bolus, a cognitive representation of food texture is formed. These physiological signals detected during oral processing are highly complex and dynamic in nature because food structure changes continuously due to mechanical and biochemical breakdown coupled with the lubricating action of saliva. Multiple and different sensations are perceived at different stages of the process. Although much work has focused on factors that determine mechanical (e. g., rheological and fracture) and sensory properties of foods, far less attention has been paid to linking food transformations that occur during oral processing with sensory perception of texture. Understanding how food structure influences specific patterns of oral processing and how these patterns relate to specific textural properties and their cognitive representations facilitates the design of foods that are nutritious, healthy, and enjoyable.
Koc H; Vinyard C J; Essick G K; Foegeding E A
Annual Review of Food Science and Technology, Vol 4
2013
2013
Book Chapter
<a href="http://doi.org/10.1146/annurev-food-030212-182637" target="_blank" rel="noreferrer noopener">10.1146/annurev-food-030212-182637</a>
Adaptation Of Oral Processing To The Fracture Properties Of Soft Solids
bolus size; chewing behavior; elastic model foods; electromyography; electromyography; Food Science & Technology; fracture properties; gel texture; gels; hardness; human mastication; jaw movement; jaw tracking; muscle-activity; oral; processing; rheology; sensory; texture
Hardness and rubberiness are distinct textural properties that are associated with extended oral processing times and therefore of interest to designing food structure for specific textural properties. Model food gels were developed with (1) increasing strength/hardness and constant deformability or (2) increasing deformability/rubberiness within a limited range of strength. Gel structures were characterized based on mechanical properties and the muscle activity (electromyography) and mandibular movements (three-dimensional jaw tracking) required for oral processing. Increased strength or deformability required more chewing cycles and increased muscle activity to breakdown samples for swallowing. In contrast, jaw movement amplitude increased in all directions with increased strength and remained constant or decreased with increased deformability. Specific mechanical properties that were correlated with oral processing parameters changed as chewing progressed, possibly reflecting a change in dominate mechanical properties and sensory perception during oral processing. Practical ApplicationsA fundamental understanding of how food structure determines sensory texture is essential to designing foods that are healthy and desirable to consumers. Oral processing, from first bite through swallowing, is the main physiological element of texture evaluation. Model soft solid foods with increasing strength/hardness or deformability/rubberiness were developed and characterized by mechanical tests and oral processing. Mastication of harder or more deformable structures required different chewing movements in bolus preparation. The specific mechanical properties relating to oral processing may change during the chewing sequence.
Koc H; Cakir E; Vinyard C J; Essick G; Daubert C R; Drake M A; Osborne J; Foegeding E A
Journal of Texture Studies
2014
2014-02
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1111/jtxs.12051" target="_blank" rel="noreferrer noopener">10.1111/jtxs.12051</a>
Using electromyography as a research tool in food science
chewing behavior; emg; Food Science & Technology; force; mastication; muscle; normalization; patterns; release; surface electromyography; texture-perception
The jaw muscles play key functional roles during feeding. During contraction, a bioelectrical signal propagates along the muscle cell helping to coordinate muscle contraction. This signal can be measured via electromyography (EMG). Food scientists have increasingly adopted EMG as a tool for studying the relationships among food textures and oral processing. Specifically, food scientists have used EMG from the feeding muscles as (1) a general measure of food texture, (2) a measure of oral physiology, (3) an estimate of absolute force and (4) a measure of muscle work. Unfortunately, physiological research indicates that estimates of absolute force and mechanical work are not reliably indicated from EMG as it is best considered an indicator of muscle activity and relative recruitment levels.
Vinyard C J; Fiszman S
Current Opinion in Food Science
2016
2016-06
Journal Article
<a href="http://doi.org/10.1016/j.cofs.2016.06.003" target="_blank" rel="noreferrer noopener">10.1016/j.cofs.2016.06.003</a>
Preference and consequences: A preliminary look at whether preference impacts oral processing in non-human primates
Anthropology; bitter taste; cebus-apella; chewing behavior; electromyography; Evolutionary Biology; fallback foods; Feeding; Food mechanical properties; Food preference; hardness; mastication; mechanical properties; model foods; muscle; patterns; texture
Non-human primates demonstrate food preferences much like humans. We have little insight, however, into how those preferences impact oral processing in primates. To begin describing this relationship, we conducted a preliminary analysis measuring food preference in two tufted capuchins (Cebus apella) and comparing ranked preference to physiological variables during chewing of these foods. Food preference was assessed for each monkey across 12 foods, including monkey biscuits and 11 foods consumed by humans (e.g., various fruits and nuts). Animals chose from randomized pairs of foods to generate a ranked scale across the 12 foods. Contemporaneous with preference testing, electromyographic (EMG) activity was measured for the jaw-closing muscles to assess oral physiology during chewing of these foods. As expected, these capuchins exhibited clear preferences among these 12 foods. Based on their preferences, we identified sets of preferred and non-preferred brittle (i.e., almond versus monkey chow) and ductile (i.e., dates and prunes versus apricots) foods for physiological comparisons that broadly control variation in food mechanical properties (FMPs). As expected, oral physiology varied with FMPs in each animal. Within brittle and ductile groupings, we observed several significant differences in chewing cycle length and relative muscle activation levels that are likely related to food preference. These differences tended to be complex and individual specific. The two capuchins chewed non-preferred apricots significantly faster than preferred dates and prunes. Effect sizes for preference were smaller than those for FMPs, supporting the previous focus on FMPs in primate dietary research. Although preliminary, these results suggest that food preference may influence oral physiology in non-human primates. The prospect that this relationship exists in monkeys raises the possibility that a link between food preference and oral processing in humans may be based on shared tendencies with non-human primates, such as aversion to bitter items or preference for sweet foods. (C) 2016 Elsevier Ltd. All rights reserved.
Vinyard C J; Thompson C L; Doherty A; Robl N
Journal of Human Evolution
2016
2016-09
Journal Article
<a href="http://doi.org/10.1016/j.jhevol.2016.07.001" target="_blank" rel="noreferrer noopener">10.1016/j.jhevol.2016.07.001</a>