Strategies to compensate for undesired gritty sensations in foods

A look upon the adsorption of different astringent agents to oral models: Understanding the contribution of alternative mechanisms in astringency

Salivary proteins precipitation by interaction with polyphenols is the major mechanism for astringency. However, alternative mechanisms seem involved in the perception of different subqualities of astringency. In this study, adsorption of four astringent agents to in vitro oral models and their sensory properties were assessed. Overall, green tea infusion and tannic acid have shown a higher adsorption potential for models with oral cells and absence of saliva. Alum and grape seed extract presented higher adsorption in models with presence of oral cells and saliva. Multiple factor analysis suggested that adsorption may represent important mechanisms to elicit the astringency of alum. Models including saliva, were closely associated with overall astringency and aggressive subquality. Models with cells and absent saliva were closely associated with greenness, suggesting a taste receptor mechanism involvement in the perception. For the first time a correlation between an oral-cell based assay and astringency sensory perception was shown.

What Is Chalky? Investigating Consumer Language and Perception of Fine Particles in Beverages Containing Pea and Potato Starch

Despite its importance as an undesirable food texture, the phenomenon of chalkiness remains understudied. Chalky sensations presumably arise from fine particulates found in foods, but semantic overlap with other common descriptors of small particles, like gritty or sandy, is unclear. Here, we compare the usage of Chalky with related descriptors, and determine the effect of particle size, concentration, and xanthan content on Chalky ratings in a model beverage. A 23 factorial design with starch particle size (D90 = 33.8 and 64.6 µm), starch concentrations (10 and 20% w/v), and xanthan content (0.075 and 0.15% w/v) was used. Participants' salivary flow rate was also assessed. A multi-sip taste test was performed where naïve consumers (n = 82; 39% men, 60% women; age range = 18-79 years) rated the intensity of Chalky, Powdery, Gritty, Sandy, Mouthdrying, and Residual mouthcoating at 0, 30, and 60 s after each of three consecutive sips. All attribute ratings were highly correlated, with Chalky, Powdery, and Residual Mouthcoating being more closely correlated with each other than Gritty or Sandy. Although Chalky was still reported 60 s after consumption, no evidence of build-up was found with repeated sips. A larger size and higher concentration increased Chalky ratings, with the low-salivary-flow group reporting greater ratings for Chalky relative to the high-flow group. Our results suggest consumer percepts of small particles are overlapping but not entirely redundant. This suggests researchers and product developers should carefully distinguish between these descriptors when trying to understand consumer perception of food products containing fine particles.

Discrimination of cellulose microparticles in rats

Oral perception of food particles is important in mastication and swallowing. However, the mechanism underlying particle perception remains poorly understood because of the lack of suitable experimental systems. We evaluated microparticle perception in rats utilizing insoluble cellulose particles of varying diameters (20-170 μm). The cellulose additives have polycrystalline morphologies and contain smaller crushed particles. The filtrate containing 20 μm particles at a concentration of 1.6% was passed through 3 μm pore-size filter paper, and numerous small particles equivalent to a 0.25 mM soluble solution were observed. In two-bottle preference tests, rats showed no innate preference or avoidance of particles of any size at concentrations ranging from 0.05-1.6%. Next, conditioned preference learning tests employing 8% glucose and fructose solutions were performed. After being repeatedly presented with glucose and fructose solutions containing particles of different sizes (170 and 20 μm particles or 20 μm filtrate) at a concentration of 1.6%, the rats preferred particles in glucose solution even without glucose presentation. Intriguingly, rats preferred the filtrate following repeated presentations of glucose-containing filtrate and water containing fructose. These results suggest that rats can distinguish microparticles in water. The preference learning test is useful for analyzing particle perception mechanisms in mammals.

Multi-attribute temporal descriptive methods in sensory analysis applied in food science: A systematic scoping review

Among descriptive sensory evaluation methods, temporal methods have a wide audience in food science because they make it possible to follow perception as close as possible to the moment when sensations are perceived. The aim of this work was to describe 30 years of research involving temporal methods by mapping the scientific literature using a systematic scoping review. Thus, 363 research articles found from a search in Scopus and Web of Science from 1991 to 2022 were included. The extracted data included information on the implementation of studies referring to the use of temporal methods (details related to subjects, products, descriptors, research design, data analysis, etc.), reasons why they were used and the conclusions they allowed to be drawn. Metadata analysis and critical appraisal were also carried out. A quantitative and qualitative synthesis of the results allowed the identification of trends in the way in which the methods were developed, refined, and disseminated. Overall, a large heterogeneity was noted in the way in which the temporal measurements were carried out and the results presented. Some critical research gaps in establishing the validity and reliability of temporal methods have also been identified. They were mostly related to the details of implementation of the methods (e.g., almost no justification for the number of consumers included in the studies, absence of report on panel repeatability) and data analysis (e.g., prevalence of use of exploratory data analysis, only 20% of studies using confirmatory analyses considering the dynamic nature of the data). These results suggest the need for general guidelines on how to implement the method, analyze and interpret data, and report the results. Thus, a template and checklist for reporting data and results were proposed to help increase the quality of future research.

Advancing textural heterogeneity: Effect of manipulating multi-component model foods on the perception of textural complexity

The aim of this study was to identify the individual and interacting effects of varying the mechanical properties of two inserts (к-carrageenan beads; 1, 2 and 4% w/w and/or agar-based disks; 0.3, 1.2 and 3% w/w) in pectin-based gels on the perception of textural complexity. A full factorial design was utilised, 16 samples were characterised with sensory and instrumental tests. Rate-All-That-Apply (RATA) was performed by 50 untrained participants. RATA selection frequency provided different information to attribute intensity regarding the detection of low yield stress inserts. In the two-component samples, the perception of textural complexity (n = 89) increased with insert yield stress for both к-carrageenan beads and agar disks. However, with the addition of medium and high yield stress к-carrageenan beads to three-component samples, the increases in perceived textural complexity caused by increased agar yield stress were eliminated. The definition of textural complexity, the number and intensity of texture sensations, as well as their interactions and contrasts, was in line with the results, and the hypothesis that not only mechanical properties but also the interaction of components play a key role in the perception of textural complexity.