Effect of Oral Physiology Parameters on In-Mouth Aroma Compound Release Using Lipoprotein Matrices: An In Vitro Approach

Oral processing of meat-flavour textured soy proteins - Part I: Bolus properties and relationships with the texture profile analysis of the products

The study of food oral processing provides relevant information about the eating process. Thus, we studied the effects of oral processing of meat-flavour textured soy proteins on bolus properties and established relationships with the texture profile of the products. The soy protein concentrate was extruded under three conditions (30 % moisture/180 °C, 34 % moisture/160 °C and 38 % moisture/140 °C). The extrudates were added with salt and monosodium glutamate and then separated into two parts, one with and one without vegetable oil, thus obtaining the flavoured textured soy proteins (FTSPs). All products were subjected to texture profile analysis and in vivo assays to study oral processing. The extrusion condition at 30 % moisture/180 °C produced FTSPs with lower hardness, cohesiveness, and chewiness, which required shorter mastication times and resulted in boluses with lower moisture and a greater number of particles, which had a greater maximum Feret diameter but were less uniform (lower circularity). The addition of oil resulted in boluses with lower moisture and fewer particles, which were less uniform. Moreover, as the mastication duration increased, the number of particles increased, but the size of the particles also increased, suggesting both fragmentation and aggregation of particles phenomena during this process. In conclusion, all the study factors influenced the oral processing of meat-flavour textured soy proteins. Therefore, more studies should be conducted to obtain more information about extruded products.

Masticatory simulators based on oral physiology in food research: A systematic review

A masticatory simulator is a mechanical device that mimics the physiological structures of the human oral cavity, chewing movement system, and functions. The advantage of this device lies in real-time tracking and analysis of food boluses within a sealed oral space, offering a direct validation platform for food experiments without constraints related to time, space, and individual variations. The degree to which the masticatory simulator simulates physiological structures reflects its efficacy in replicating oral physiological processes. This review mainly discusses the physiological structures of the oral cavity, the simulation of biomimetic components, and the development, feasibility assessment, applications, and prospects of masticatory simulators in food. The highlight of this review is the analogy of biomimetic component designs in masticatory simulators over the past 15 years. It summarizes the limitations of masticatory simulators and their biomimetic components, proposing potential directions for future development. The purpose of this review is to assist readers in understanding the research progress and latest literature findings on masticatory simulators while also offering insights into the design and innovation of masticatory simulators.

Flavor release from walnut kernels in an in-vitro mastication model with decoupled oral parameters

Consumer preferences for walnut products are largely determined by the flavors released during mastication. In this study, a peeled walnut kernel (PWK) model was established with oral parameters decoupled using a Hutchings 3D model. The model explored in vitro variations using head-space solid-phase microextraction-gas chromatography-mass spectrometry and intelligent sensory techniques. The fracture strength, hardness, particle size, adhesiveness, springiness, gumminess, and chewiness were significantly reduced during mastication. We identified 61 volatile compounds and found that 2,5-dimethyl-3-ethylpyrazine is a key component, releasing predominantly baking and milky notes. Glutamic acid, alanine, arginine, and sucrose were identified as the key compounds in taste perception. The method can help establish a mastication model for nuts and facilitate breakthroughs in the development of walnut products and processing methods.

Influence of Cheese Composition on Aroma Content, Release, and Perception

The quality of a cheese is determined by the balance of aroma compounds primarily produced by microorganisms during the transformation of milk into ripened cheese. The microorganisms, along with the technological parameters used in cheese production, influence aroma formation. The perception of these compounds is further influenced by the composition and structure of the cheese. This study aimed to characterize how cheese composition affects aroma compound production, release, and perception. Sixteen cheeses were produced under controlled conditions, followed by a quantitative descriptive analysis post ripening. Aroma composition was analyzed using HS-SPME-GC-MS, and a dynamic sensory evaluation (TCATA) was combined with nosespace analysis using PTR-ToF-MS. Image analysis was also conducted to characterize cheese structure. Cheese fat and whey lactose contents were identified as key factors in the variability of sensory attributes. GC-MS analyses identified 27 compounds correlated with sensory attributes. In terms of aroma compound release, 23 ions were monitored, with fat, salt, and lactose levels significantly affecting the release of most compounds. Therefore, cheese fat, salt, and whey lactose levels, as well as the types of microbial strains, play a role in influencing the composition, structure, release of aroma compounds, and sensory perception.

Comparison of Child and Adult Mastication of a Sticky Processed Cream Cheese and Simulation with a Masticator

An advantage of masticators is the calibration and possible standardization of intra- and inter-individual mastication variability. However, mastication of soft, sticky and melting products, such as processed cream cheeses, is challenging to reproduce with a masticator. The objectives of this work were, for the cheese studied: (1) to compare child and adult mastication and (2) to find in vitro parameters which best reproduce their in vivo chewing. Five parameters influencing mastication (mouth volume, quantity consumed, saliva volume, mastication time and number of tongue-palate compressions) were measured in 30 children (5-12 years old) and 30 adults (18-65 years old) and compared between the two populations. They were then transposed to a masticator (Oniris device patent). The initial cheese, a homogeneous white paste, was surface-colored to investigate its in-mouth destructuring. In vivo boli were collected at three chewing stages (33, 66 and 99% of mastication time) and in vitro boli were obtained by varying the number of tongue-palate compressions and the rotation speed. In vivo and in vitro boli were compared by both image and texture analysis. Child masticatory parameters were proportionally smaller than those of adults. The in vivo child boli were less homogeneous and harder than adult ones. Comparison of in vivo and in vitro bolus color and texture enabled the successful determination of two in vitro settings that closely represented the mastication of the two populations studied.

Recent trends in aroma release and perception during food oral processing: A review

The dynamic and complex peculiarities of the oral environment present several challenges for controlling the aroma release during food consumption. They also pose higher requirements for designing food with better sensory quality. This requires a comprehensive understanding of the basic rules of aroma transmission and aroma perception during food oral processing and its behind mechanism. This review summarized the latest developments in aroma release from food to retronasal cavity, aroma release and delivery influencing factors, aroma perception mechanisms. The individual variance is the most important factor affecting aroma release and perception. Therefore, the intelligent chewing simulator is the key to establish a standard analytical method. The key odorants perceived from the retronasal cavity should be given more attention during food oral processing. Identification of the olfactory receptor activated by specific odorants and its binding mechanisms are still the bottleneck. Electrophysiology and image technology are the new noninvasive technologies in elucidating the brain signals among multisensory, which can fill the gap between aroma perception and other senses. Moreover, it is necessary to develop a new approach to integrate the relationship among aroma binding parameters, aroma concentration, aroma attributes and cross-modal reactions to make the aroma prediction model more accurate.

Retronasal Aroma of Beef Pate Analyzed by a Chewing Simulator

In retronasal aroma, the targeted aroma compounds are released from food during chewing. The changes in the food structures during chewing strongly influence the release of the compounds, therefore affecting the perception of food. Here, the relationship between retronasal aroma and food deliciousness based on the physicochemical properties of aroma compounds was examined. We considered the consumption of solid foods and the effect of oral parameters in elderly people. Beef pate was used as a model food sample to study the effect of the release of aroma compounds under controlled in vitro mastication and salivation conditions using a chewing simulator. We identified the effects of coexisting ingredients such as beef fat on the time course behavior of the release of aroma compounds. In particular, the release of the middle types of aromas was significantly faster with stronger chewing force, and higher with a high fat content of the sample. In addition, a larger release intensity was observed when soy proteins were partially substituted for beef proteins. Using an appropriate model saliva, a change in the salting-out effect from the saliva composition was found to be a factor, which could explain the lowering of aroma sensation in an elderly person.

Current Perspectives on Food Oral Processing

Food oral processing (FOP) is a fast-emerging research area in the food science discipline. Since its first introduction about a decade ago, a large amount of literature has been published in this area, forming new frontiers and leading to new research opportunities. This review aims to summarize FOP research progress from current perspectives. Food texture, food flavor (aroma and taste), bolus swallowing, and eating behavior are covered in this review. The discussion of each topic is organized into three parts: a short background introduction, reflections on current research findings and achievements, and future directions and implications on food design. Physical, physiological, and psychological principles are the main concerns of discussion for each topic. The last part of the review shares views on the research challenges and outlooks of future FOP research. It is hoped that the review not only helps readers comprehend what has been achieved in the past decade but also, more importantly, identify where the knowledge gaps are and in which direction the FOP research will go.

Influence of Fat Replacers on the Rheological, Tribological, and Aroma Release Properties of Reduced-Fat Emulsions

Reduced-fat food products can help manage diet-related health issues, but consumers often link them with poor sensory qualities. Thus, high-quality fat replacers are necessary to develop appealing reduced-fat products. A full-fat model emulsion was reduced in fat by replacing fat with either water, lactose, corn dextrin (CD), inulin, polydextrose, or microparticulated whey protein (MWP) as fat replacers. The effect of fat reduction and replacement, as well as the suitability of different types of fat replacers, were determined by analyzing fat droplet size distribution, composition, rheological and tribological properties, and the dynamic aroma release of six aroma compounds prevalent in cheese and other dairy products. None of the formulations revealed a considerable effect on droplet size distribution. MWP strongly increased the Kokini oral shear stress and viscosity, while CD exhibited similar values to the full-fat emulsion. All four fat replacers improved the lubricity of the reduced-fat samples. Butane-2,3-dione and 3-methylbutanoic acid were less affected by the changes in the formulation than butanoic acid, heptan-2-one, ethyl butanoate, and nonan-2-one. The aroma releases of the emulsions comprising MWP and CD were most similar to that of the full-fat emulsion. Therefore, CD was identified as a promising fat replacer for reduced-fat emulsions.

Dynamic release and perception of key odorants in grilled eel during chewing

The release mechanism of odorants in the oral cavity during consumption directly affects sensory attributes, consumers' preferences, and ultimately purchase intent. Targets was set to monitor in real-time the key odorants released from grilled eel during mastication via an atmospheric pressure chemical ionization mass spectrometry (APCI-MS) connected with a nose interface. The release and perception of odorants during mastication were divided into three distinct phases. Dimethyl sulfide was the main odorant in the first stage. The release and perception of fishy aromas were predominant in the middle and last stages of mastication contributed by trimethylamine, 1-penten-3-ol, and 2-methyl-1-butanol. Chewing behavior experiments suggested that extending the chewing period to >20 s and having a chewing frequency of 2 cycles/s could enhance the aroma delivery of grilled eel and optimize the consumer experience. Consequently, the results explained the relationship between aroma release and the optimal chewing behavior for grilled eel consumption.

In Vivo Aroma Release and Dynamic Sensory Perception of Composite Foods

Condiments such as spreads, dressings, or sauces are usually consumed together with carrier foods such as breads or vegetables. Dynamic interactions between condiments and carriers occur during consumption, which can influence aroma release and perception. This study investigated in vivo aroma release (PTR-MS) and dynamic sensory perception (time-intensity) of mayonnaises spiked with lemon aroma (limonene, citral). Mayonnaises were assessed without and with carrier foods (bread, potato). When different mayonnaises were consumed and assessed alone, aroma release and intensity perception were positively correlated. Interestingly, when mayonnaises were combined with carriers, aroma release and perception were no longer positively correlated. Addition of carriers increased release of limonene and citral into the nasal cavity during consumption but decreased perceived aroma intensity of condiments. The increase in aroma release induced by the carriers can be explained by differences in oral processing behaviors and by the increased surface area of mayonnaise-carrier combinations. Carrier addition is likely to modulate aroma perception of composite foods by cross-modal texture-aroma interactions. This work demonstrates that not only physicochemical characteristics of foods but also cross-modal interactions play a role in influencing flavor perception of composite foods.

Compilation of data on model cheeses composition, rheological and sensory properties, from six research projects exported from the BaGaTel database

This paper presents data on model cheeses extracted from the BaGaTel database. The data are issued from 6 different research projects in which data on composition, rheological and sensory properties were collected. The manufacturing of the 68 different samples is described. For each model cheese, data are available on final composition (lipid, protein, water, sodium), rheological properties (uniaxial compression), sensory profile analysis (texture, taste, aroma) and for some cheeses chewing activity and in vivo sodium release were also measured. The material and methods used are detailed. Scatter plots of representation of the values for each variable and each project are plotted. Pearson correlations between variables are given for specific subsets of data. The dataset is hosted in an open access data repository. This dataset will allow a comparison of sensory properties of cheeses varying in lipid, protein water and salt content and can be used for the reformulation of cheeses made with a low salt and fat content to follow food-related health recommendations, whilst fulfilling good sensory qualities.

Development of a Chewing Robot With Built-in Humanoid Jaws to Simulate Mastication to Quantify Robotic Agents Release From Chewing Gums Compared to Human Participants

Medicated chewing gum has been recognised as a new advanced drug delivery method, with a promising future. Its potential has not yet been fully exploited because currently there is no gold standard for testing the release of agents from chewing gum in vitro. This study presents a novel humanoid chewing robot capable of closely replicating the human chewing motion in a closed environment, incorporating artificial saliva and allowing measurement of xylitol release from the gum. The release of xylitol from commercially available chewing gum was quantified following both in vitro and in vivo mastication. The chewing robot demonstrated a similar release rate of xylitol as human participants. The greatest release of xylitol occurred during the first 5 minutes of chewing and after 20 minutes of chewing only a low amount of xylitol remained in the gum bolus, irrespective of the chewing method used. Saliva and artificial saliva solutions respectively were collected after 5, 10, 15 and 20 minutes of continuous chewing and the amount of xylitol released from the chewing gum determined. Bioengineering has been implemented as the key engineering strategy to create an artificial oral environment that closely mimics that found in vivo. These results demonstrate the chewing robot with built-in humanoid jaws could provide opportunities for pharmaceutical companies to investigate and refine drug release from gum, with reduced patient exposure and reduced costs using this novel methodology.

Oral Processing Studies: Why Multidisiciplinary?

When food is ingested, it remains in the mouth for a short period of time. Although this period is brief compared to the total food nutrient digestion and absorption time, it is crucially important as it is the first step in digestion. It is also very important that, while the food is in the mouth, it is perceived by the senses and then a decision is made on swallowing. Oral sensory perception is an integrative response, which is generated in very short time (normally a few seconds) from complex information gathered from multiple sources during mastication and swallowing. Consequently, food oral processing studies include many orientations. This Special Issue brings together a small range of studies with a diversity of approaches that provide good examples of the complexity and multidisciplinarity of the subject.