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This work is focused on the study of freeze-thaw behavior of double (W1/O/W2) emulsions by the application of a cooling-heating-cooling cycle by differential scanning calorimetry. Emulsions were prepared with sodium caseinate as hydrophilic emulsifier in outer aqueous (W2) phase and sunflower oil (SO) and/or interesterified vegetable fat (VF) plus polyglycerol polyricinoleate as lipophilic emulsifier in lipid phase. The effects of sodium chloride concentration in inner aqueous (W1) phase and solid fat content in lipid phase were analyzed. In all cases, W1 phase froze at lower temperature than W2 phase because higher undercooling was required for the crystallization of inner water droplets. In the absence of VF, the system with low salt concentration showed water diffusion from undercooled W1 phase to frozen W2 phase at the first cooling stage, due to the lower vapor pressure of ice. However, at the second cooling stage, this phenomenon was not observed and partial recovery of inner water was detected, probably because of an osmotic effect. The increase of salt concentration allowed a higher retention of inner water after freezing of W2 phase, attributed to the lowered vapor pressure of W1 phase. The loss of inner water was also restrained or prevented by the presence of VF in lipid phase due to the immobilization of water droplets within a fat crystal network. The crystallization behavior of SO was related to inner water quantity and VF content. This study could be useful for the formulation of W1/O/W2 emulsions with enhanced freeze-thaw stability.

This paper focuses on the comparative study of emulsifying properties of dried tofu-whey, dried soy-whey and their isolated proteins. Oil-in-water emulsions were prepared at equivalent protein concentration (0.1, 0.5 and 1.0 g/100 mL), using sunflower oil as lipid phase (oil mass fraction = 0.33). Tofu-whey and soy-whey were dehydrated by freeze-drying (LTW and LSW, respectively) or thermal-drying (DTW and DSW, respectively). Moreover, a heated LSW sample in anhydrous condition (h-LSW) was included. The emulsion formation and stability at rest was evaluated using a vertical scan analyzer, according to multiple light scattering theory, particle size and oiling off measurements. Even though the stability to gravitational separation and coalescence increased with increasing protein concentration, freeze-dried whey samples exhibited a higher ability to form and stabilize emulsions respect to that of thermally-dried ones, especially for those obtained from soy-whey. Moreover, h-LSW emulsions were more stable than that of LSW sample presumably due to protein glycosylation. The global emulsion stability decreased in the order: LTW>DTW>h-LSW>LSW>DSW. Moreover, at equivalent protein concentration in the continuous phase, the isolation of proteins from lyophilized whey-samples by treatment with cold acetone (LTW-P, LSW-P and h-LSW-P, respectively) improved their emulsifying properties. Again, this improvement was more pronounced for samples obtained from soy-whey, probably due to partial protein denaturation associated to treatment with the organic solvent. In conclusion, this paper should be considered as basis for further studies concerned with the potential application of soy-whey and tofu-whey proteins as emulsifiers in different systems.

The objective of this work was to develop a corrected method for solid fat content estimation by differential scanning calorimetry (DSC), as important differences are usually observed between the results given by DSC and pulsed nuclear magnetic resonance (NMR). Cold storage after full melting of fats was necessary to avoid the appearance of exothermic peaks in the modulated temperature DSC thermograms, in order to make an appropriate estimation of melting energy. Different fats were analyzed by NMR and DSC, obtaining considerably higher solid fat content values with the latter, uncorrected method. These differences were attributed to the fact that consumed energy per unit of melted mass tends to increase with the increase of the melting temperature of each fraction of the fats. A linear correlation between melting enthalpy and melting point of different triglycerides was used to estimate the energy per unit of mass consumed at each temperature. From these data, an estimated transformation of melting energy into melted mass was performed and new solid fat content values were calculated. The results obtained from this correction were much closer to the measurements made by NMR, in comparison to the uncorrected DSC method.

Soybean hull is an agroindustrial waste which has not been fully studied as a food ingredient. The aims of this work were to obtain insoluble fibers from soybean hull and to evaluate the effect of high pressure homogenization (HPH) on its physicochemical properties. Hull insoluble polysaccharides (HIPS) were obtained in a single step, as the insoluble residue after pectin removal. FTIR showed bands corresponding to cellulose and hemicellulose in HIPS, and thermogravimetric analysis showed two degradation events at 236.3 °C and 325.6 °C, corresponding to cellulose and hemicellulose, respectively. HIPS dispersions (pH 3.00) were subjected to HPH by three cycles at increasing pressures (up to 1000 bar), obtaining soybean hull nanofibers. SEM images show that HPH at 1000 bar reduced the dimensions of the fiber bundle from 30 to 90 μm in length and 9–15 μm in diameter to nanofibers of 10–30 μm in length and 100–400 nm in diameter. AFM further confirms a heterogeneous distribution of sizes in HIPS800 and HIPS1000, evidencing the presence of individual nanofibers with diameters around 50 ± 10 nm and 40 ± 10 nm, respectively, with several μm in length. Furthermore, an increase in water holding capacity from 2.1 to 61 gwater/gdry matter and viscosity from 0.39 to 34,945 Pa.s were achieved as HPH at 1000 bar treatment was applied. HPH increased the interfacial area and promoted the interconnection of fibers in a hydrated gel-like structure. This explains flow behavior, which was extensively studied in this work: three-region viscosity profile (shear-thinning, plateau or shear-thickening and shear-thinning) and a pronounced hysteresis loop. Oscillatory rheology was used to study the viscoelastic behavior of HIPS dispersions. HIPS are a source of nanofibers, easy to obtain through a single step of chemical treatment followed by the application of high pressures. It is remarkable that the use of few chemical solvents is favorable from an environmental point of view. This work also suggests a potential application of HIPS to improve physicochemical and structural properties in acidic foods.

Pain involves sociocultural and psychosocial dimensions that influence the experience and expression of the pain phenomenon, as well as the human and technological resources required for its care. This article seeks to understand the meaning attributed by elderly people to care of the person in old age who experiences pain and discuss it from the approach to pain in public health practices. The research was developed using a qualitative anthropological approach and based on the intersubjective contact between the researcher and the individuals researched. Individual semi-structured interviews were conducted with 57 elderly people. The methodology of Signs, Meanings and Actions governed the collection and analysis of the data to investigate behavior associated with pain. The meaning of care of pain in public health practices was observed in three analytical categories, namely pain in the context of life, language in the care of the person in pain, and the pain inflicted in care practices. The care of pain in health care is not limited to the organic aspect, but it mobilizes the whole existence of the elderly person, interferes in the communicative process and causes suffering. Care of pain must include the users in the therapeutic process and mobilize them to regain control over their lives.Pain involves sociocultural and psychosocial dimensions that influence the experience and expression of the pain phenomenon, as well as the human and technological resources required for its care. This article seeks to understand the meaning attributed by elderly people to care of the person in old age who experiences pain and discuss it from the approach to pain in public health practices. The research was developed using a qualitative anthropological approach and based on the intersubjective contact between the researcher and the individuals researched. Individual semi-structured interviews were conducted with 57 elderly people. The methodology of Signs, Meanings and Actions governed the collection and analysis of the data to investigate behavior associated with pain. The meaning of care of pain in public health practices was observed in three analytical categories, namely pain in the context of life, language in the care of the person in pain, and the pain inflicted in care practices. The care of pain in health care is not limited to the organic aspect, but it mobilizes the whole existence of the elderly person, interferes in the communicative process and causes suffering. Care of pain must include the users in the therapeutic process and mobilize them to regain control over their lives.

The influence of the variation of different parameters on the particle size distribution and solid fat content (SFC) of water-in-oil emulsions was studied. The use of solid fat instead of liquid oil, higher polyglycerol polyricinoleate (PGPR) concentration, or higher homogenization energy led to smaller mean particle sizes. The decrease of the emulsifier/water ratio turned the particle size distribution of the emulsions from bimodal to trimodal. The increase of PGPR concentration increased the SFC of the fat in the absence of water, but it did not produce the same effect in the emulsion. This result suggested that the presence of dispersed aqueous phase prevented the modifying action of the emulsifier on the crystallization of the continuous lipid phase. The experimentation indicated that the adsorption of the surfactant at the interface would reduce its availability to affect crystallization in bulk fat, as the SFC in lipid phase decreased with increasing interfacial area.

The aim of this work was to study the effect of xanthan gum (XG) on the gelation process of bovine sodium caseinate (NaCAS) induced by acidification with glucono-δ-lactone (GDL) and on the mixed acid gel microstructure. Before GDL addition, segregative phase separation was observed in all the NaCAS-XG mixtures evaluated. The gelation process was analyzed by using a fractional factorial experimental design. The images of the microstructure of the mixed acid gels were obtained by conventional optical microscopy and the mean diameter of the interstices was determined. Both the elastic character and the microstructure of the gels depended on the concentrations of XG added. As XG concentration increased, the kinetics of the gelation process was modified and the degree of compactness and elasticity component of the gel network increased. The microstructure of gels depends on the balance among thermodynamic incompatibility, protein gelation and NaCAS-XG interactions.

In old age, the ailing patient's body becomes estranged and reveals an awareness of alterity. This paper investigates how the body of the elderly addresses the estrangement as a subject, producing its own actions in the experience of disease and practice of public health. The research, developed using the qualitative approach of an anthropological nature, is based on the assumptions of ethnography. Individual interviews with a semi-structured script in the universe of 57 elderly people were conducted. The methodology of Signs, Meanings and Actions oriented the data collection and analysis enabling the investigation of representations and concrete behaviors associated with the otherness of the body. There was the sense of production of otherness in relation to two analytical categories associated with aging and disease. A split between the active body of the memory and another experienced with limitations in the present is detected, reflecting the confrontation of self-care and adherence to treatment. The body of the elderly individual is heir to a body image that remodels constantly, depriving the elderly of their place as contemporary owners of their bodies, as they become other persons.

The present study compares the emulsifying properties in acidic conditions of hull soluble polysaccharides (HSPS), soybean soluble polysaccharides (SSPS) and its mixtures. These fractions were obtained from byproducts of soybean processing industry (soy hull and residual fiber after isolation of soy cotyledon protein, respectively). Although SSPS is already characterized, HSPS is a novel fraction which has not been studied in deep and it is still unexplored as emulsifier. Dispersions of both fraction and a mixture 50:50 of them at pH 3.0 were used as aqueous phase (1.0–3.0 % w/w ) in coarse and fine oil-in-water emulsions (oil mass fraction = 0.3). Its stability was evaluated through the evolution of backscattering profiles (%BS), particle size distribution and mean particle diameters. The rheology of the emulsions was also analyzed. Both fractions provided stability to creaming when increasing the polysaccharide concentration and energy of homogenization. While coarse emulsions were unstable systems, fine emulsions were stable enough and allowed a deeper analysis of the destabilizing processes. A bridging flocculation phenomenon in the presence of HSPS and HSPS/SSPS mixtures is suggested, which influences the creaming and rheological behavior. Also, coalescence index increases according HSPS and HSPS/SSPS concentrations, but particle sizes reached were smaller than in SSPS emulsions. Fine emulsions with 3 % of HSPS/SSPS mixtures yielded the best results on the overall stability at 28 days. So, functional properties of the fractions may improve by the formulation of emulsions consisting in mixtures of them. These results are of interest to the manufacturing of acidic foods, taking advantage of obtaining byproducts from residual materials.

The objective was to analyze the microstructure, stability, and rheology of model emulsions prepared with distilled water, refined sunflower oil, and different Spans (20, 40, 60, and 80) as emulsifiers. The effects of the water content and Span 60 concentration were studied. The lowest water contents led to w/o emulsions, whereas higher percentages gave w/o/w emulsions. Microscopy analysis showed that w/o/w emulsions of higher water contents had a lower number of internal water droplets. W/o emulsions were destabilized by coalescence and sedimentation, whereas creaming was observed in unstable w/o/w emulsions. In the last ones, the creaming stability decreased with increasing water content and enhanced with higher Span 60 concentration; the same effect was observed in their viscoelasticity: They were from unstable liquids to stable gels. Solid Spans (40 and 60) produced more consistent w/o/w emulsions at low water contents and more stable systems at high water percentages in comparison with liquid Spans (20 and 80).