Structural Properties and Phase Model Interpretation of the Tertiary System Comprising Gelatin, Agarose and a Lipid Phase

Considerable attention has been paid to emulsion gels (EGs) in recent years due to their interesting applications in food. The aim of this work is to shed light on the role played by chia oil in the technological and structural properties of EGs made from soy protein isolates (SPI) and alginate. Two systems were studied: oil-free SPI gels (SPI/G) and the corresponding SPI EGs (SPI/EG) that contain chia oil. The proximate composition, technological properties (syneresis, pH, color and texture) and structural properties using Raman spectroscopy were determined for SPI/G and SPI/EG. No noticeable (p > 0.05) syneresis was observed in either sample. The pH values were similar (p > 0.05) for SPI/G and SPI/EG, but their texture and color differed significantly depending on the presence of chia oil. SPI/EG featured significantly lower redness and more lightness and yellowness and exhibited greater puncture and gel strengths than SPI/G. Raman spectroscopy revealed significant changes in the protein secondary structure, i.e., higher (p < 0.05) α-helix and lower (p < 0.05) β-sheet, turn and unordered structures, after the incorporation of chia oil to form the corresponding SPI/EG. Apparently, there is a correlation between these structural changes and the textural modifications observed.

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Quantifications of Oleocolloid Matrices Made of Whey Protein and Oleogels

Foods ◽

10.3390/foods9111697 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1697

Author(s):

Clifford Park ◽

Rafael Jimenez-Flores ◽

Farnaz Maleky

Keyword(s):

Protein Content ◽

Whey Protein ◽

Structural Properties ◽

Rice Bran ◽

Protein Denaturation ◽

Hydrophobic Interactions ◽

Lipid Phase ◽

Food Protein ◽

Rice Bran Wax ◽

Colloidal Interactions

Consumer demand for high protein content and plant-based fat has necessitated novel approaches to healthy food products. In response to this need, oleogels (OG) (structured liquid oils) emerged as a possible means of not only replacing saturated and trans fats but also delivering food protein. Nevertheless, an in-depth view of the structure of networks made of OG and protein is deficient. Hence, the objective of this study is developing oleocolloid (OC) (whey protein and rice bran wax OG) and hydro-oleocolloid (HOC) (OC + water) matrices with varying protein content (2.5–7.5%) to characterize their structural properties. Thermal analysis of the matrices via differential scanning calorimetry (DSC) documented the effects of hydrophobic interactions on the protein structure and its stability. Whey protein denaturation temperature increased from 74.9 °C to 102.8 °C in the presence of high oleic soybean oil. The effects of vegetable oil on WPI structure was also verified by FTIR spectroscopy. Data analysis revealed slight structural changes of the WPI secondary structure in the hydrophobic oil medium and the α-helix and β-sheet proportion in the emulsion medium was significantly altered. Similar analysis was performed in OC and HOC networks to quantify possible interactions between protein and rice bran wax. Results indicated that the protein was denatured during the thermal and mechanical conditions required for the oleogelation process, while it did not affect the systems’ solid fat content (SFC) and polymorphic patterns of the oleogels. However, DSC analysis showed different onset of melting for OC and HOC samples due to colloidal interactions between the protein and the lipid phase. The role of these chemistry was confirmed by microscopy analyses where OC and HOC matrices displayed notably different microstructural properties. The observed differences in the structural properties between OC and HOC matrices indicate the different colloidal interactions mediated by oleogelation process and the liquid medium type (oil vs. emulsion).

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DSC and DMTA study of annealed cold-drawn PET: a three phase model interpretation

Polymer ◽

10.1016/s0032-3861(03)00589-5 ◽

2003 ◽

Vol 44 (19) ◽

pp. 5771-5777 ◽

Cited By ~ 37

Author(s):

A. Bartolotta ◽

G. Di Marco ◽

F. Farsaci ◽

M. Lanza ◽

M. Pieruccini

Keyword(s):

Phase Model ◽

Model Interpretation ◽

Three Phase

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Geometric structural properties of bonded layers of chemically modified silicas

Journal of Chromatography A ◽

10.1016/s0021-9673(01)91460-8 ◽

1988 ◽

Vol 447 (3) ◽

pp. 103-116 ◽

Cited By ~ 2

Author(s):

A Fadeev

Keyword(s):

Structural Properties ◽

Chemically Modified ◽

Chemically Modified Silicas

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Electronic, vibrational and structural properties of alkali halide clusters

Physica B Condensed Matter ◽

10.1016/s0921-4526(84)92608-5 ◽

1984 ◽

Vol 127 (1-3) ◽

pp. 214-218 ◽

Cited By ~ 14

Author(s):

T MARTIN

Keyword(s):

Structural Properties ◽

Alkali Halide

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Newborn's Preference for Faces

European Psychologist ◽

10.1027/1016-9040.1.3.200 ◽

1996 ◽

Vol 1 (3) ◽

pp. 200-205 ◽

Cited By ~ 12

Author(s):

Carlo Umiltà ◽

Francesca Simion ◽

Eloisa Valenza

Keyword(s):

Visual System ◽

Structural Properties ◽

Sensory Properties ◽

Human Face ◽

System Experiment ◽

Face Experiment

Four experiments were aimed at elucidating some aspects of the preference for facelike patterns in newborns. Experiment 1 showed a preference for a stimulus whose components were located in the correct arrangement for a human face. Experiment 2 showed a preference for stimuli that had optimal sensory properties for the newborn visual system. Experiment 3 showed that babies directed their attention to a facelike pattern even when it was presented simultaneously with a non-facelike stimulus with optimal sensory properties. Experiment 4 showed the preference for facelike patterns in the temporal hemifield but not in the nasal hemifield. It was concluded that newborns' preference for facelike patterns reflects the activity of a subcortical system which is sensitive to the structural properties of the stimulus.

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