Journal of texture studies最新文献

Freeze-dried (FD) fruit and vegetable materials with a large amount of sugar are unstable. With the aim to understand the structure formation of FD products, the effects of fructose content on the texture and microstructure of FD matrix were investigated by using pectin–cellulose cryogel model. Cryogels containing fructose of 0–40% were produced using freeze-drying at three different primary drying temperatures of −40, −20, and 20°C. The resultant cryogels were characterized by texture profile analyzer, scanning electron microscope, and μCT. Results indicated that at drying temperature of −40°C, increasing fructose concentration promoted the hardness of the cryogels, and cryogels of 16% fructose obtained maximum hardness. Excessive fructose (≥20%) weakened the described hardness, while exhibiting stronger springiness and resilience. The microstructure showed that dense pores and increased wall thickness due to fructose aggregation were critical factors responsible for increased hardness. The porous structure as well as relatively large pore size were necessary for crispness, in addition, rigid pore wall with certain strength were also required. At the drying temperature of 20°C, large hetero-cavities dominated the microstructure of cryogels with 30% and 40% fructose, caused by melting inside during FD process. In this situation, lower T_m (−15.48 and −20.37°C) were responsible for cryogels’ melting In conclusion, if possible, regulating fructose content and state may enable the precision texture design of FD fruit and vegetable foods.

To reproduce the tactile perception of multiple contacts on the human tongue surface, it is necessary to use a pressure measurement device with high spatial resolution. However, reducing the size of the array sensing unit and optimizing the lead arrangement still pose challenges. This article describes a deconvolution neural network (DNN) for improving the resolution of tongue surface tactile imaging, which alleviates this tradeoff between tactile sensing performance and hardware simplicity. The model can work without high-resolution tactile imaging data of tongue surface: First, in the compression test using artificial tongues, the tactile image matrix (7 × 7) with low resolution can be acquired by sensor array with a sparse electrode arrangement. Then, through finite element analysis modeling, combined with the distribution rule of additional stress on the two-dimensional plane, the pressure data around the existing detection points are calculated, further expanding the tactile image matrix data amount. Finally, the DNN, based on its efficient nonlinear reconstruction attributes, uses the low-resolution and high-resolution tactile imaging matrix generated by compression test and finite element simulation, respectively, to train, and outputs high-resolution tactile imaging information (13 × 13) closer to the tactile perception of the tongue surface. The results show that the overall accuracy of the tactile image matrix calculated by this model is above 88%. Then, we deduced the spatial difference graph of the resilience index of the three kinds of ham sausages through the high-resolution tactile imaging matrix.

With the aggravation of the global aging process, more and more elderly people are facing the problem of dysphagia. The advantages of three-dimensional (3D) printing in making chewy food are increasingly prominent. In this study, the two-nozzle 3D printer was used to explore the effects of different proportions of buckwheat flour, printing filling ratio, microwave power, and time on the quality of bean-paste buns. The results showed that the bean paste filling containing 6% buckwheat flour had the best antioxidant and sensory properties. When the filling ratio was 21.6%, the microwave power was 560 W, and the time was 4 min, the obtained sample was the most satisfactory. Compared with the microwave-treated and steamed traditional samples, the chewiness of the samples was reduced by 52.43% and 15.14%, respectively, and the final product was easier to chew and swallow.

Gels combined with honey might generate new possibilities of textures in food development. This work explores the structural and functional properties of gelatin (5 g/100 g), pectin (1 g/100 g), and carrageenan (1 g/100 g) gels with different content of honey (0–50 g/100 g). Honey decreased the transparency of gels and made them more yellow-greenish; all of them were firm and uniform, especially at the highest honey content. The water holding capacity increased (63.30–97.90 g/100 g) and moisture content, water activity (0.987–0.884) and syneresis (36.03–1.30 g/100 g) decreased with the addition of honey. This ingredient modified mainly the textural parameters of gelatin (Hardness: 0.82–1.35 N) and carrageenan gels (Hardness: 2.46–2.81 N), whereas only the adhesiveness and the liquid like-behavior were increased in the pectin gels. Honey increased the solid behavior of gelatin gels (G': 54.64–173.37 Pa) but did not modify the rheological parameters of the carrageenan ones. Honey also had a smoothing effect on the microstructure of gels as observed in the scanning electron microscopy micrographs. This effect was also confirmed by the results of the gray level co-occurrence matrix and fractal model's analysis (fractal dimension: 1.797–1.527; lacunarity: 1.687–0.322). The principal component and cluster analysis classified samples by the hydrocolloid used, except the gelatin gel with the highest content of honey, which was differentiated as a separate group. Honey modified the texture, rheology, and microstructure of gels indicating that it is possible to generate new products to be used in other food matrices as texturizers.

This research was aimed to quantify the effects of acetic acid, malic acid, and citric acid (0, 0.5, 1.0, and 2.0 g/100 g H₂O) on the stress–strain responses of fish gelatin (FG) gels (2, 4, and 6.67 g/100 g H₂O) under uniaxial compression up to 68% of deformation. The first-order Ogden model fitted quite well for the compression responses of FG gels (R² = 0.9909–0.9997). Protons from the acids played a key role on weakening the FG gel structures (gel rigidity, μ, decreased 11%–27%), as the μ values and pH values of FG gels were linearly correlated (R² = 0.8240–0.9748), regardless of the acid type. The addition of an acid also resulted in a significant increase (p < .002) in the strain hardening capacity (α) of gels with 2 g FG/100 g H₂O. Both μ and α values of FG gels with higher gelatin concentrations were less affected by an acid partly due to their stronger buffering effects. The μ and α values of FG gels as affected by acids could not be fully explained based upon the pH changes, implying that the effects of acetate, malate, and citrate ions on the gel structure could not be ignored.

Global interest in high-protein foods has been rapidly increasing and the gluten-free products are no exceptions. Gluten-free extruded noodles made from rice flour were thus fortified with soy protein concentrate (SPC) (0%, 15%, 30%, and 45% by weight), and the physicochemical properties of the noodles were characterized in terms of tomographical, rheological, and structural features. SPC-rice flour blends showed higher water absorption and swelling power at room temperature with increasing levels of SPC, which were reduced upon heating. The flour blends with high-levels of SPC also had lower pasting viscosities. Thermal analysis showed lower enthalpy values and higher temperatures derived from starch gelatinization. When the SPC-rice flour blends were applied to extruded gluten-free rice noodles, the noodles tomographically showed a dense and compact structure, that could be favorably correlated with their textural changes (increased hardness and reduced extensibility). FTIR analysis presented the structural changes of the noodles containing different levels of SPC by showing higher intensity of protein-related absorption peaks and lower starch peak intensity, which could be associated with the reduced cooking loss. Moreover, there existed two water components with different mobilities in the noodles whose spin–spin relaxation times had a tendency to increase with increasing SPC content. The results obtained from this study provided fundamental insights into the processing performance of protein-rich ingredients in gluten-free extruded noodles, probably promoting the development of a wider variety of protein-fortified gluten-free products.

The purpose of this study was to improve the method of using an inclined parallel plate (IPP) in directly estimating the yield stress $��{\tau }_{\mathrm{iy}}�$ and evaluating the properties of a thickened liquid. The flow curve of the relationship between the shear rate and shear stress of a liquid thickened with a xanthan gum agent was predicted using the Herschel–Bulkley fluid model ($��\tau �=�{\tau }_y�+�k�{\dot{\gamma }}^{�n�-�1�}�$). We supposed that the yield stress $��{\tau }_y�$ and the result of a line spread test (LST) indicate the deformation state and the flow state of shear stress ($��k�{\dot{\gamma }}^{�n�-�1�}�$), respectively. $��{\tau }_{\mathrm{iy}}�$, the yield stress $��{\tau }_{\mathrm{ry}}�$ estimated adopting a rotational viscometer and LST, was investigated for three liquids thickened with xanthan gum at four concentrations (C) at intervals of 0.5 wt% within the range 0.5–2.0 wt%. Linear plots of the relations of $��C�$ versus $��{\tau }_{\mathrm{iy}}�$ and $��{\tau }_{\mathrm{ry}}�$ and the LST show that with an increase in $��C�$, the resistance force ($��{\tau }_{}$

The events occurring before and during the merging of a model liquid food emulsion with saliva have been captured ex vivo using confocal microscopy. In the order of a few seconds, millimeter-sized drops of liquid food and saliva touch and are deformed; the two surfaces eventually collapse, resulting in the merging of the two phases, in a process reminiscent of emulsion droplets coalescing. The model droplets then surge into saliva. Based on this, two distinct stages can be distinguished for the insertion of a liquid food into the oral cavity: A first phase where two intact phases co-exist, and the individual viscosities and saliva–liquid food tribology should be important to texture perception; and a second stage, dominated by the rheological properties of the liquid food–saliva mixture. The importance of the surface properties of saliva and liquid food are highlighted, as they may influence the merging of the two phases.

Pork fat (PF) is a necessary ingredient in making traditional fish cakes (TFCs), which contains saturated fatty acids with potential health concerns. While linseed oil (LO) containing α-linolenic acid is a potential nutrient-enhancing fat substitute. In this study, the effect of pork fat and linseed oil level on gel quality, sensory characteristics, microstructure, and protein conformation of TFCs were characterized. Results showed that the TFCs with 30% pork fat (wt/wt) had the highest gel strength. Additionally, sensory evaluation determined that TFCs with 30% pork fat scored the best by a sensory panel with high gel strength, water-holding capacity, and fresh and sweet taste. The gel strength, chewiness, and hardness of nutrient-enriched fish cakes with 20% linseed oil replaced for pork fat were higher than that only with pork fat (wt/wt) without changing in tenderness and elasticity. Visual results showed that the network was uniform at a moderate level of linseed oil addition (20% LO/PF replacement ratio). The results of this study provided technical guidelines for standardizing the TFC manufacture processes, and useful insight for the development of fish cakes with reduced animal fat content for additional health benefits for consumers.

Previous studies dealing with plant-based meat analogs confirmed the potential of oral processing methods to identify options for improving those products. Knowing that sensory perception can be influenced by adding condiments, this short communication aimed to investigate the texture and oral processing of four plant-based burger analogs and a beef burger when consumed in portions or as part of model meals with buns and sides. Texture profile analysis indicated that beef burgers and analog E were the toughest. Two analogs (B and S) showed textures close to beef, while one (analog D) displayed significantly lower values for hardness, toughness, cohesiveness, and springiness. The instrumental data was only partly reflected in the mastication parameters. Adaptations in mastication behavior were expected, but differences between the plant-based analogs were smaller than anticipated, although clear differences were observed for consumption time, number of chews and number of swallows. On the whole, mastication patterns concurred within different consumption scenarios (portions, model burgers), and significant correlations with instrumental texture were obtained.