Effect of stabiliser classes (animal proteins,vegetable proteins,starches, hydrocolloids and dietary fibre) on the physicochemical properties of a model lean meat product

The effects of eleven ingredients (originating from various ingredient classes: animal proteins, plant proteins, starches, hydrocolloids and fibres) applied in two different concentrations on drip loss, rheological characteristics and hardness were evaluated in a lean meat model system. The high concentration of potato starch, insoluble citrus fibre, rice starch or pea protein significantly (P < 0.05) reduced drip losses (6.92%, 17.87%, 15.70%, 17.60%, respectively) compared to control (30.80%), while rheological measures and hardness remained unchanged (P > 0.05). Moreover, the addition of low concentrations of soluble citrus fibre did not significantly affect hardness (4.11 N), whereas its inclusion at high concentrations had a significant effect on the final hardness (7.17 N). Among all the tested ingredients, xanthan presented the lowest drip loss value (0.12% and 0.40% for high and low concentration, respectively). Finally, gelatine did not show any differences in water holding capacity, storage modulus nor hardness compared with the control group.     

Effect of carboxymethylcellulose and locust bean gums on some of physicochemical,mechanical, and textural properties of extruded rice

Extrusion is a composite process consisting of many different unit operations such as mixing, cooking, pasting, and molding. In this process, the raw material is forced through a tiny opening to be transformed into a product with a desired and unique shape, texture, color, and taste. In combination with different amounts and types of additives, this technique can result in functional food products for a broad range of people suffering from micronutrient deficiency. The hydrocolloid compounds are now employed to improve the texture and performance properties of many food products. Therefore, this study scrutinized the effects of carboxymethylcellulose and locust bean gums at different levels (0.5, 0.75, and 1%) alone or in combination with each other on chemical, physical, mechanical, and textural properties of extruded rice in comparison with the qualitative properties of the control rice. A completely random design was used along with three replications to analyze the test results. Then the means were compared through Duncan's multiple range test at (α = 5%). According to the results, addition of gums increased moisture, ash, total color difference, water absorption capacity, solubility, failure force, rupture energy, elasticity module, and toughness when reduced lateral expansion was compared to the control. Moreover, the addition of gums after the cooking process increased cooking loss, texture hardness, chewability, and elasticity of the specimens in comparison with the control. According to the results of pre‐ and post‐cooking tests, the specimens containing locust (0.75%) and carboxymethylcellulose (0.75%) gums were the best treatments.     

Oleogel production based on binary and ternary mixtures of sodium caseinate,xanthan gum,and guar gum: Optimization of hydrocolloids concentration and drying method

We report the optimization of oleogel formulation based on sodium caseinate (CN, 0–4 g/100 g), xanthan gum (XG, 0–1 g/100 g), guar gum (GG, 0–1 g/100 g), and drying method (freeze and oven drier) using response surface methodology to achieve the desired oil binding capacity, textural, and rheological attributes. All the selected responses were successfully fitted by a quadratic model with determination coefficient values higher than .95 with the exception of firmness values which was fitted by linear model. There were considerable increases in all the responses for the samples containing ternary mixtures of protein-gum (CN:XG:GG) as well as binary mixtures (CN:GG and CN:XG) compared to samples containing protein or gums alone due to the synergistic effect of CN and gums on formation of highly ordered and strong gel network. Regression modeling demonstrated that freeze drying method led to significantly greater structure recovery values than those of oven drying method. The best formulation was the freeze dried oleogel containing 4 g/100 g CN, 0.43 g/100 g XG, and 0.98 g/100 g GG. Results showed that fabrication of oleogels with at least 94.5 g/100 g sunflower oil and characteristics similar to industrial shortening is feasible.     

Steady and dynamic oscillatory shear rheological properties of ketchup-processed cheese mixtures: Effect of temperature and concentration

The steady and dynamic shear properties of ketchup-processed cheese (K-PC) mixtures were investigated at different temperatures (10-50 °C) and PC concentrations (0-30%). The K-PC mixtures showed a shear-thinning behavior with low magnitudes of yield stress. The consistency coefficient (K) and apparent viscosity (η₅₀) decreased with increase in temperature and concentration. The mixtures followed the Arrhenius temperature relationship, indicating that the magnitudes of activation energies (E_a) were in the range of 8.83-17.16 kJ mol⁻¹. Storage (G′), loss (G′′) and complex (G∗) modulus increased with increase in frequency while complex viscosity (η∗) decreased. The K-PC mixtures at concentrations of 0-15% exhibited weak gel-like behavior. Increase in the PC concentration resulted in a decrease in G∗, G′, G′′ and η∗ up to the 15% of PC concentration, showing a plateau value between 0% and 30% concentrations. Cox-Merz rule was not applicable to K-PC mixtures.     

Effect of hydrocolloids on physicochemical,sensory and textural properties of reconstructed rice grain by extrusion cooking technology

Cracked or broken rice grains followed by lower rice efficiency during processing and milling of rice paddy are a major challenge contributing to the reduced economic productivity of this branch of industry. Therefore, the extrusion process for turning flour from broken rice or wastes into complete rice grains can bring about value-added for producers. In addition, an optimized formulation can improve product diversity and nutritional value. In this study, the effect of addition of Guar and Arabic gums on physicochemical, texture and sensory profiles of extruded rice grains was analyzed. Both gums were used in four concentrations (0.1, 0.2, 0.3 and 0.4 w/w %, d.b), and the effect of their different levels on properties of extruded rice was studied. Results from physicochemical tests on extruded rice samples showed that moisture content, water solubility index, water absorption index and bulk density were increased in samples containing higher concentration of Guar than Arabic gum and initial moisture content of 30% compared to no-gum samples, whereas lateral expansion, cooking loss, and total color change (ΔE) were reduced. Furthermore, results showed that higher levels of Guar than Arabic gum led to an improvement in sensory and textural properties.     

皮革手感品质神经网络分类方法

在选取了皮革手感品质表征参数的基础上,建立了皮革手感品质分类BP神经网络模型。通过样本的训练和模拟,结果证明:基于所选取的表征参数的皮革手感品质分类神经网络,经过训练可以准确地对皮革手感品质进行分类。     

Effect of selected Hofmeister salts on textural and rheological properties of nonfat cheese

Three Hofmeister salts (HS; sodium sulfate, sodium thiocyanate, and sodium chloride) were evaluated for their effect on the textural and rheological properties of nonfat cheese. Nonfat cheese, made by direct acidification, were sliced into discs (diameter = 50 mm, thickness = 2 mm) and incubated with agitation (6 h at 22°C) in 50 mL of a synthetic Cheddar cheese aqueous phase buffer (pH 5.4). The 3 HS were added at 5 concentrations (0.1, 0.25, 0.5, 0.75, and 1.0 M) to the buffer. Post-incubation, cheese slices were air dried and equilibrated in air-tight bags for 18 h at 5°C before analysis. Small amplitude oscillatory rheology properties, including the dynamic moduli and loss tangent, were measured during heating from 5 to 85°C. Hardness was determined by texture profile analysis. Acid-base buffering was performed to observe changes in the indigenous insoluble (colloidal) calcium phosphate (CCP). Moisture content decreased with increasing HS concentration. Cheeses incubated in high concentrations of SCN⁻ softened earlier (i.e., loss tangent = 1) compared with other HS treatments. Higher melting temperature values were observed for cheeses incubated in high concentrations of SO₄²⁻. Hardness decreased in cheeses incubated in buffers with high concentrations of SCN⁻. The indigenous CCP profile of nonfat cheese was not greatly affected by incubation in Cl⁻ or SCN⁻, whereas buffers with high concentrations of SO₄²⁻ reduced the acid-base buffering contributed by CCP. The use of high concentrations (1.0 M) of SCN⁻ for incubation of cheeses resulted in a softer protein matrix at high temperatures due to the chaotropic effect of SCN⁻, which weakened hydrophobic interactions between CN. Cheese samples incubated in 1.0 M SO₄²⁻ buffers exhibited a stiffer protein matrix at high temperatures due to the kosmotropic effect of SO₄²⁻, which helped to strengthen hydrophobic interactions in the proteins during the heating step. This study showed that HS influenced the texture and rheology of nonfat cheese probably by altering the strength of hydrophobic interactions between CN.     

Effects of mulberry pomace on physicochemical and textural properties of stirred-type flavored yogurt

Adding functional ingredients is an important method to develop functional dairy products. Mulberry pomace (MPo), a byproduct of mulberry fruit processing, is rich in phenolic compounds and anthocyanins and can be served as the functional ingredient in functional dairy products. The aim of this work was to prepare a functional flavored yogurt by incorporating MPo into stirred yogurt and to investigate the effects of MPo on the physicochemical and textural properties of the product during cold storage. We supplemented MPo powder up to 3% (wt/wt) in fermented milk, and the changes in color, pH, titratable acidity (TA), total phenol content (TPC), total anthocyanin content (TAC), water-holding capacity, rheological behavior, texture, and microstructure of the functional flavored yogurt were monitored during storage under 4°C for 28 d. The MPo powder brought a pink to dark red color to the yogurt, decreased the lightness (L*) and yellow-blue color (b*) values, increased the red-green color (a*) values, decreased the pH value, and increased the contents of TA, TPC, and TAC in a dose-dependent manner. The addition of MPo at 1%, 2%, and 3% (wt/wt) significantly increased water-holding capacity, consistency, viscosity, and viscosity index, and reduced firmness of yogurt samples. Supplementation of MPo significantly reduced the pore spaces and channels inside the samples and improved microstructure of the functional yogurt. During the 28 d of cold storage, MPo-fortified yogurt samples kept relatively constant color, although their L*, a*, and b* showed a decreasing tendency. The pH of all yogurt samples gradually decreased with increasing of TA. Interestingly, TPC and TAC contents and the texture parameters of MPo-fortified yogurt increased gradually and continuously during the 28 d of cold storage. Mulberry pomace is beneficial to improve the physicochemical and textural properties of yogurt and has the potential as a natural stabilizer to be used in functional yogurt rich in phytochemicals.     

Influence of xanthan gum and gluten on in vitro digestibility and textural properties of rice bread

Starch digestibility of gluten-free bread has been expected to be suppressed for the purpose of decreasing glycemic response. The objective of this study was to investigate the effects of adding xanthan gum and gluten on starch and protein digestibility of rice bread prepared using the developed recipe involving pickering stabilization of foams and emulsions. The extent of starch digestion of gluten-free bread was suppressed by adding 2% xanthan gum from 79.8% to 57.3%. This suppressive effect was diminished by using gluten and that of rice bread containing 2% xanthan gum and 20% gluten was 75.5%. The extent of starch digestion of gluten-free bread was similar or less than that of bread containing gluten. The gluten-free bread with 2% xanthan gum had significantly lower loaf volume, porosity, and sticker structure of breadcrumb than the control. The suppressive effects of xanthan gum on starch and protein digestion were mainly dependent on reducing accessibility of the enzyme into the inner structure.     

The effect of rice bran on physicochemical,textural and glycaemic properties of ready-to-eat extruded corn snacks

In this work, corn extruded snack products were enriched with rice bran (RB) at 10% and 15%. A co-rotating twin-screw extruder was used with a feed moisture content of 16 g 100 g⁻¹, a screw speed of 240 r.p.m. and four heating sections of the barrel (100, 140, 150 and 150 °C). The impact of RB inclusion on nutritional profile, starch digestion, physicochemical and textural properties of snack products was evaluated. RB-enriched extrudates showed a lower specific volume and hardness and higher crispness than control. RB at 15% gave a water-holding capacity lower than control. Rheology of extrudate dispersions indicated an increase in elastic interactions and solid-like behaviour with RB supplementation. Differences in rheological properties resulted in attenuation of predictive glycaemic response for RB-enriched snacks.     

Impact of particle size distribution on rheological and textural properties of chocolate models with reduced fat content

ABSTRACT:  With an increasing consumption of lipids nowadays, decreasing the fat content in food products has become a trend. Chocolate is a fat-based suspension that contains about 30%wt fat. Reducing fat content causes an increase in the molten chocolate viscosity. This leads to 2 major issues: difficulties in the process and a loss of eating quality in the final product, reported to have poor in-mouth melting properties, remain hard, and difficult to swallow. Literature shows that optimizing the particle size distribution (PSD), that is, having one with an increased packing fraction, can decrease the viscosity of highly concentrated suspensions. This study focuses on the impact of the PSD and fat content on the rheological properties, melting behavior, and hardness of chocolate models (dispersions of sugar in fat). We show that optimizing the PSD while reducing the fat content to a critical amount (22%wt) can decrease the viscosity of the molten material and reduce the hardness of the crystallized chocolate models. Melting in the mouth, characterized by an in vitro collapse speed, is faster for the samples with an optimized PSD. The decrease in the viscosity by optimizing the PSD in systems with a constant fraction of medium phase is based on the decrease of interparticle contact, reducing the particle aggregates strength, and structure buildup during flow or meltdown. In its crystallized state, the particle network is less interconnected, providing less resistance to breakage and meltdown.     

Effect of guar gum on the rheological, thermal and textural properties of soybean β-conglycinin gel

The effect of guar gum, a non-gelling neutral polysaccharide, on the thermal gelation of soybean β-conglycinin was analysed using the dynamic oscillatory rheological measurement, differential scanning calorimetry and texture profile analysis. The endothermic peak temperature of β-conglycinin in the presence of 0.5% guar gum was about 89.1 °C. However, the endothermic peaks shifted to higher temperatures as the guar gum concentration increased from 0.05% to 0.5%, which could be attributed to the thermodynamic incompatibility with guar gum, resulting in a promoted aggregation of the thermally denatured β-conglycinin. Furthermore, the elastic modulus increased with increasing concentration of guar gum, with a less frequency dependence. In addition, the springiness, cohesiveness and fracturability enhanced but the hardness decreased, as the guar gum concentration increased. The study demonstrated that incorporation of guar gum improved markedly the thermal and functional properties of soybean β-conglycinin thermal-induced gel, which can help better to design new food formulations.     

Effect of xanthan gum on the physical properties and textural characteristics of whipped cream

Xanthan gum was used as thickening agent to prepare whipped cream in this work. A dose-dependent effect was observed on the average particle size (d_3,2) of whipped cream. At each xanthan gum level (0.025–0.125%) used, whipping time also showed a positive effect on the average particle size. With the increase of xanthan gum level or whipping time, the partial coalescence of fat in the whipped cream increased gradually. However, xanthan gum level showed no significant effect on the overrun of whipped cream. The textural characteristics of whipped cream were also investigated and the results indicated that a positive correlation was found between xanthan gum level and firmness, cohesiveness or viscosity of whipped cream. A different tendency was detected for consistency. The consistency of whipped cream increased with the increase of xanthan gum level to 0.100%, thereafter decreased.     

A combined approach in characterization of an effective w/o hand cream: the influence of emollient on textural, sensorial and in vivo skin performance

To formulate a consumer-acceptable cosmetic product, numerous demands have to be fulfilled, and as the most important, efficacy (both real and perceived), adequate aesthetic (visual perception) and all sensorial characteristics have to be achieved. In this study, four model water-in-oil creams intended for hand care, varying in one emollient component, were submitted to rheological, sensory and textural characterization, and their efficacy was evaluated in in vivo study on human volunteers. Our results indicate that certain alteration restricted to the oil phase induced a change in all investigated characteristics, showing that each instrumental measurement can be used as a sensitive tool in the characterization of cream samples. Regarding the correlation between physical measurements and certain sensory attributes, it is possible to formulate a product with specific sensory characteristics by using pre-defined rheological or textural parameters. To obtain a complete sensory profile of a cosmetic product, a detailed sensory evaluation should be carried out according to the existing standard practices, which are both time- and money-consuming. However, a modified sensory study could be useful for fast in-line screening along with instrumental characterization of a novel cosmetic emulsion product and could be particularly helpful in the process of distinguishing a single formulation from several differing in one component.     

Effect of substituting whey cream for sweet cream on the textural and rheological properties of cream cheese

In the manufacture of cream cheese, sweet cream and milk are blended to prepare the cream cheese mix, although other ingredients such as condensed skim milk and skim milk powder may also be included. Whey cream (WC) is an underutilized fat source, which has smaller fat droplets and slightly different chemical composition than sweet cream. This study investigated the rheological and textural properties of cream cheeses manufactured by substituting sweet cream with various levels of WC. Three different cream cheese mixes were prepared: control mix (CC; 0% WC), cream cheese mixes containing 25% WC (25WC; i.e., 75% sweet cream), and cream cheese mixes with 75% WC (75WC; i.e., 25% sweet cream). The CC, 25WC, and 75WC mixes were then used to manufacture cream cheeses. We also studied the effect of WC on the initial step in cream cheese manufacture (i.e., the acid gelation process monitored using dynamic small amplitude rheology). Acid gels were also prepared with added denatured whey proteins or membrane proteins/phospholipids (PL) to evaluate how these components affected gel properties. The rheological, textural, and sensory properties of cream cheeses were also measured. The WC samples had significantly higher levels of PL and insoluble protein compared with sweet cream. An increase in the level of WC reduced the rate of acid gel development, similar to the effect of whey phospholipid concentrate added to mixes. In cream cheese, an increase in the level of added WC resulted in significantly lower storage modulus values at temperatures <20°C. Texture results, obtained from instrumental and sensory analyses, showed that high level of WC resulted in significantly lower firmness or hardness values and higher stickiness compared with cream cheeses made with 25WC or CC cream cheeses. The softer, less elastic gels or cheeses resulting from the use of high levels of WC are likely due to the presence of components such as PL and proteins from the native milk fat globule membrane. The use of low levels of WC in cream cheese did not alter the texture, whereas high levels of WC could be used if manufacturers want to produce more spreadable products.