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With growing consumer demand for plant‐based products that mimic the eating experience of animal‐based products, there is a need for improvement in instrumental measurements of sensory texture. This study aimed to characterize textural differences between dairy and non‐dairy cheeses, and to investigate whether Large Amplitude Oscillatory Shear (LAOS) rheometry could discriminate sensory texture better than Texture profile analysis. Commercial dairy and non‐dairy cheddar, mozzarella, and cream cheese were selected to provide a wide range of textures. Sensory evaluation used the check‐all‐that‐apply methodology with 73 consumers. Texture profile analysis force‐distance data were analyzed empirically, and also converted to stress and strain (see https://shiny.csiro.au/texture%5fdash). The major textural differences between dairy and non‐dairy cheddar were related to structural cohesion, according to both instrumental measures (dairy cheddar had 1.5‐fold higher failure stress and 2.2‐fold higher failure strain) and sensory measurements (dairy cheddar was more chewy and less crumbly). In contrast, cream cheeses showed similar textural properties using sensory testing but significant instrumental differences (non‐dairy cream cheese had 5.7‐fold higher modulus of deformability, 4.7‐fold higher failure stress). For mozzarella, there were large differences in both sensory attributes (chewy, crumbly, jelly‐like, stretchy) and instrumental parameters (13.6‐fold difference in modulus, 2.7‐fold difference in failure stress). LAOS rheometry gave insights into the mechanisms by which samples absorbed or dissipated mechanical energy at nonlinear strains. The LAOS parameter G3′/G1′$$ {G}_3^{\prime }/{G}_1^{\prime } $$ correlated well with sensory attributes creamy, fatty/oily, and moist, indicating the potential of this technique to measure structural phenomena linked to sensory attributes that resonate with consumers. [ABSTRACT FROM AUTHOR]

This study examined the effects of spread formulation and the structural/lubricant properties of six different commercial hazelnut and cocoa spreads on sensory perception. Rheology, tribology, and quantitative descriptive analysis (QDA) was assessed by also evaluating the correlation coefficients between the quality descriptor and the rheological and textural parameters. The viscosity was evaluated at different temperatures to better simulate conditions before and after ingestion. Tribological analysis was executed at 37°C to mimic the human oral cavity. The effect of saliva presence and the number of runs on tribological behaviors was investigated. Moreover, textural, calorimetric, and particle size distribution measurements were performed to reinforce the correlation between structural/thermal parameters (e.g., firmness, stickiness, sugar melting point) and sensory aspects. "Visual viscosity," defined as a sensory attribute evaluated prior to consumption, negatively correlated with apparent viscosity measured at 20°C and 10 s−1, whereas "body," defined during oral processing and related to creaminess, positively correlated with apparent viscosity measured at 37°C and 50 s−1. These attributes were mainly influenced by particulate microstructure and solid volume fraction within the formulation. Textural stickiness positively correlated with sensory "adhesiveness" and was related to fat composition and milk powder addition, while "sweetness" was related to sucrose content and sugar melting enthalpy. Tribological data provided meaningful information related to particle‐derived attributes, as well as after‐coating perception (fattiness/oiliness), thus better predicting food evolution during oral consumption. [ABSTRACT FROM AUTHOR]

In recent years, the extraction, processing, and application of edible gums, in the food and healthcare sector has skyrocketed and extensively explored. Edible gums are derived from multiple sources such as plants/trees, animals, microorganisms, and seaweed. Edible gums are typically employed to perform certain functions including modification of rheology, gel formation, stability, encapsulation, and fat replacement. The unique interaction of edible gums with food molecules enables the achievement of desired characteristics of specific food products belonging to various sectors. This review delivers a comprehensive understanding of the classification and characterization of edible gums and their applications in the food industry. Despite several advantages offered by edible gums, there exist certain challenges that are encountered during commercialization by manufacturers and proposed strategies to overcome the hurdles, regulatory aspects, and safety of edible gums upon consumption have been highlighted in this review. [ABSTRACT FROM AUTHOR]

Food texture is a collective term for all texture‐related features of a food product. A comprehensive description of food texture is therefore practically challenging due to too many parameters that are associated simultaneously with the food. Using every day, non‐technical (layman's) language, we attempt in this work to rationalize the different dimensions that contribute to the texture of foods, and we explain the rheological reasons behind the concept. For solid foods, three dimensions are identified being the "hard–soft," "strong–weak," and "brittle–plastic." For liquid foods, three further dimensions are suggested, being "elastic–viscous," "thick–thin," and "shear thinning–shear thickening." As these dimensions are bipolar, for foods where any of the dimensions are not relevant, we conceive that dimension takes on a zero value, aligning at the center of the scale. [ABSTRACT FROM AUTHOR]

Food processes have been requiring increasingly more accurately designed operations. Successful design results in products with high quality, in addition to offering energy and cost savings. To these ends, fundamental knowledge regarding the physical properties and thermodynamic mechanisms of the material is essential. The aim of this review was to highlight important concepts and applications of some thermophysical properties (density, specific heat, thermal conductivity and thermal diffusivity), as well as recent methods for their determination. The rheology of fluids and solids is widely discussed according to the concepts, classification, modeling and applications involved in food and equipment design. Herein, we report destructive and non-destructive assays for the evaluation of food properties. Due to the complexity of food systems, the effects of modifications of the structure and physicochemical reactions on the quality of the resulting food are addressed based on thermodynamic aspects. This analytical perspective was adopted in food systems rich in fats, proteins, polysaccharides and simple sugars. Using the information reported in this study, formulations and unit operations can be better designed. In addition, process failures become more predictable when fundamental knowledge is available. Therefore, food losses can be avoided, quality can be maintained and operations can be effectively resumed when deviations from ideal conditions are evidenced. [ABSTRACT FROM AUTHOR]

Five commercial hazelnut/cocoa spreads with different compositions were tested by rheology/tribology. The impact of each formulation on the structural/lubricant performances was investigated. Rotational/oscillatory rheology was chosen to assess material behavior during flow. Viscosity variation as a function of temperature and chamber geometry was evaluated. Oscillatory mode tests were carried out to obtain information on product viscoelasticity. Tribological analysis was performed at different temperatures aiming at simulating the chewing/swallowing process. All samples were categorized as pseudo‐plastic and viscoelastic materials, with the elastic component prevailing over the viscous one. Major differences were detected in terms of consistency index, depending on the total lipid content. Temperature increase enhanced spread fluidity with a decreasing viscosity according to the Arrhenius model (R2 > 0.942) and greater values of activation energy reflecting higher sensitivity to microstructural changes. An inverse relationship between Casson viscosity ηc and sugar/fat ratio highlighted additional correlations between structural parameters and spread formulation. Tribological measurements at 25°C highlighted that, at the initial eating stage, the friction factor (0.112–0.262 at sliding velocity of 8 × 10−6 m/s) was strongly affected by either the amounts of solid fat or hazelnut percentage. Tribological data corroborated the theory for which tribology and rheology cover different domains. [ABSTRACT FROM AUTHOR]

In this work, extra-virgin olive oil (EVO)- and sunflower oil (SFO)-based oleogels were structured using rice bran wax (RBW) at 10% by weight (w/w). Bamboo fiber milled with 40 (BF40), 90 (BF90) and 150 (BF150) µm of average size was added as a structuring agent. The effect of fiber addition and cooling temperature (0, 4, and 25 °C) on thermal and structural parameters of achieved gels was assessed by rheological (both in rotational and oscillatory mode), texture, and differential scanning calorimetry tests. Oleogelation modified the rheological behavior of EVO and SFO, thus shifting from a Newtonian trend typical of oils to a pseudoplastic non-Newtonian behavior in gels. Moreover, oleogels behaved as solid-like systems with G′ > G″, regardless of the applied condition. All samples exhibit a thermal-reversible behavior, even though the presence of hysteresis suggests a partial reduction in structural properties under stress. Decreasing in cooling temperature negatively contributed to network formation, despite being partially recovered by low-granulometry fiber addition. The latter dramatically improved either textural, rheological, or stability parameters of gels, as compared with only edible oil-based systems. Finally, wax/gel compatibility affected the crystallization enthalpy and final product stability (gel strength) due to different gelator–gelator and gelator–solvent interactions. [ABSTRACT FROM AUTHOR]

Microbial polysaccharides have interesting and attractive characteristics for the food industry, especially when produced by food grade bacteria. Polysaccharides produced by lactic acid bacteria (LAB) during fermentation are extracellular macromolecules of either homo or hetero polysaccharidic nature, and can be classified according to their chemical composition and structure. The most prominent exopolysaccharide (EPS) producing lactic acid bacteria are Lactobacillus, Leuconostoc, Weissella, Lactococcus, Streptococcus, Pediococcus and Bifidobacterium sp. The EPS biosynthesis and regulation pathways are under the dependence of numerous factors as producing-species or strain, nutrient availability, and environmental conditions, resulting in varied carbohydrate compositions and beneficial properties. The interest is growing for fruits and vegetables fermented products, as new functional foods, and the present review is focused on exploring the EPS that could derive from lactic fermented fruit and vegetables. The chemical composition, biosynthetic pathways of EPS and their regulation mode is reported. The consequences of EPS on food quality, especially texture, are explored in relation to producing species. Attention is given to the scientific investigations on health benefits attributed to EPS such as prebiotic, antioxidant, anti-inflammatory and cholesterol lowering activities. [ABSTRACT FROM AUTHOR]

For playing a role of filling a hole in the applicable range of standard rheometer, ultrasonic spinning rheometry (USR) is presented; it is based on equation of motion to explain the fluid rheology and to quantify the rheological properties satisfying the considered equation of motion for complex fluids. Some examples of rheological evaluation for multi-phase fluids using USR were presented; clay dispersion with thixotropy, polymer solution with large-spherical particles, dessert paste with pectin gel including fruit pulps. The efficacy of USR was discussed through those practical tests for complex fluid. [ABSTRACT FROM AUTHOR]

The aim of this paper was to study, step by step, the effect of ingredients and storage conditions on several properties of both the maize-based dough and the final product, during the new polenta-based snack food developing. Two different maize flours were characterized through water activity determination, particle size analysis, scanning electronic microscopy; then, dough made with different ratio of these were evaluated for mechanical properties and microstructure. According to the preliminary physicochemical characterization of both flour and dough, the final formulation was chosen for the polenta-based snacks. Thus, mechanical and sensory analyses, as well as microstructure determination, were performed on the final product. Results showed that the two maize flours presented different particle size distribution and gelatinization enthalpy, and affected the mechanical properties of intermediate products. The storage conditions dramatically affected the characteristics of the final products. Sensory results demonstrated that breading improves the crispness of external part but keeping creamy the product inside. The chosen approach was useful for understanding that flour particle size and storage are the critical factors that should be considered for this type of snack. The best formulation was made by mixing coarse and fine maize flours and by adding a batter. [ABSTRACT FROM AUTHOR]

This review summarised the compositional, thermal, and rheological properties and food applications of chestnut ( Castanea spp.) flour systems. The compositional, structural, and physicochemical properties of chestnut starch, which is a major determinant for product quality, were also reviewed. Future research directions on how to better utilise chestnut flour and starch for food product developments were suggested. Chestnuts are important food items for many people around the world. The world production of chestnuts has kept increasing during the last decade. There has been growing interest to utilise chestnut flour for various food applications (e.g. gluten-free food products). The major component of chestnut is starch which amounts to over 50% of the dry weight of the fruit. Chestnut starch may as well have potential for food and non-food applications. Overall, this review provides a scientific basis to develop chestnuts as sustainable and cash crops. [ABSTRACT FROM AUTHOR]

To assess the effect of food form (FF) on postprandial (PP) plasma amino acid (AA) concentrations, ten older adults (five men and five women, age 72 (sem 2) years, BMI 26·0 (sem 0·9) kg/m2) consumed, on separate days, energy and macronutrient-matched test meal replacement products (MRP) (approximately 25 % of the subject's daily energy need; approximately 54 % carbohydrate, 21 % protein, 25 % fat) in beverage and solid form. Blood samples were taken during fasting and throughout the 4 h PP period; plasma AA concentrations were assessed using HPLC. Consumption of each MRP led to an increase in total AA, branched-chain AA (BCAA), essential AA (EAA), non-essential AA (NEAA) and leucine concentrations (4 h area under the curve, AUC) (time effect; P < 0·05). The beverage MRP resulted in a greater initial (i.e. 30 min) and sustained (4 h AUC) increase in total AA, BCAA, EAA, NEAA and leucine concentrations compared with the solid MRP (each effect of FF; P < 0·05). Although there was no effect of FF on PP insulin response, glucose concentration was greater 1 and 2 h after the solid MRP was consumed (FF × time interaction; P < 0·05). For all PP time points combined, total AA concentration was positively associated with plasma insulin (r 0·25) and glucose (r 0·24) concentrations for the solid MRP but not for the beverage MRP. In conclusion, older adults can achieve higher plasma AA concentrations when a protein-containing MRP is ingested in beverage form. The implications of the higher AA availability on anabolic processes warrant investigation. [ABSTRACT FROM PUBLISHER]

The purpose of the present study was to determine whether a protein-rich beverage leads to a differential response in appetite, satiety and subsequent energy intake compared with an energy- and macronutrient-matched solid version in young people. A total of fifteen adolescents (eight girls and seven boys; age 14 (sem 1) years, BMI percentile 79 (sem 4) %) randomly completed two testing days that included protein-rich (PR) breakfast meals (38 % of energy as protein, 48 (sem 2) g/meal) provided as a solid (S) or beverage (B). Breakfast was 24 % of estimated daily energy needs (2146 (sem 96) kJ/meal). Perceived appetite and satiety responses were collected over 5 h followed by an ad libitum lunch buffet. The PR-S meal led to greater reductions in 4 h postprandial appetite ( − 6221 (sem 1171) mm × 240 min) v. the PR-B meal ( − 3570 (sem 957) mm × 240 min; P < 0·05). When examining the data according to hourly responses, the PR-S meal led to greater reductions in appetite during postprandial hours 2, 3 and 4 v. the PR-B meal (all comparisons, P < 0·05). No differences in postprandial hourly or total (4 h) fullness were observed following the PR-S v. PR-B meals. The PR-S meal led to approximately 480 kJ less energy consumed at the ad libitum lunch buffet (1418 (sem 222) kJ) v. the PR-B meal (1900 (sem 326) kJ; P < 0·05). These data indicate that, although the food form of the PR breakfast meals had little, if any, effect on satiety, the appetitive responses were diminished and the subsequent food intake was greater when protein was consumed as a beverage v. a solid meal. [ABSTRACT FROM PUBLISHER]

The effects of the dehydration-rehydration process on the recovering of the original rheological characteristics of the re-hydrating solution were studied. Four different fruit fluid products were investigated: apricot, banana purees, non-pureed citrus fruits, i.e mandarin juice and lemon treacle, respectively. The static rheological behavior of both pureed and non-pureed products was measured for the raw material, i.e. before the drying process, and after the rehydration procedure. First of all, the results show that rehydrated materials have different rheological behaviors from fresh ones, especially in the case of starch added non-pureed products. Such differences can be due to both the stress conditions induced by mechanical drying and successive rehydration or to other factors such as, for example, the starch addition. These results were relevant to quantify the rehydration efficacy of pureed and non-pureed foods, suggesting than more than just one parameter should be controlled for liquid foods when the rehydration procedure is carried out. [ABSTRACT FROM AUTHOR]

In the present study, rheological properties of twelve different licorice root extracts were evaluated using a rotational viscometer as a function of soluble solids content (15–45 °Bx) and temperature (30–70 °C). Response Surface Methodology was used to understand the relationships between the parameters. The experimental data were then fit into mathematical models. The results, for the first time, revealed that the licorice solutions had non-Newtonian shear-thinning behaviors with flow behavior indexes of 0.24 to 0.91, depending on the licorice extract samples, temperature, and °Bx. These observations were different from those reported in the literature and the present study elaborated on reasons for such observations. Further, the shear-thinning behavior generally increased by increasing the °Bx and decreasing the temperature. In addition, the power-law model was found to be suitable for predicting the experimental data. The newly revealed information can be particularly important in designing the unit operations for licorice extract processing. [ABSTRACT FROM AUTHOR]

The basic food science course at Leeds University takes four years and leads to the degree of B.Sc. Since entrants have variable mathematical ability the food rheology course is divided into a basic non-mathematical course for all students in the second year and a mathematical component for selected students only, in the fourth. Courses are kept up to date by a study of the literature, and the circulation of questionnaires to the British Food Industry. [ABSTRACT FROM AUTHOR]