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1.
Food Sci Nutr ; 11(6): 3131-3140, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37324841

ABSTRACT

Herein, the effect of incorporation of rosemary essential oil (REO) nanoemulsions with the smallest (98.14 nm) and largest (148.04 nm) droplets' sizes at different concentrations (0%, 2%, and 4% v/v) in Eremurus luteus root gum (ELRG) coating solution on microbial, chemical, and sensory qualities of chicken fillets during cold storage was investigated. The results demonstrated a significant reduction in pH and TBA value and total viable microbial count (TVC) of chicken meat samples after using an active ELRG coating compared with the uncoated sample. Moreover, the properties of active ELRG coatings were more affected by the concentration of REO nanoemulsions than the size of their droplets. More antimicrobial and antioxidant activities were observed in coated samples containing 4% (v/v) REO nanoemulsions (L-4 and S-4). The highest and lowest pHs at the end of storage belonged to uncoated (6.89) and S-4 coated (6.41) samples, respectively. Unlike the control sample (8th day), the microbial population in the active coated samples (>12th day) reached the threshold level (7 log CFU/g) later. The TBA value in the control and coated samples was 0.56 and 0.4-0.47 mg/kg after 12 days of cold storage, respectively. Increasing the REO nanoemulsion content from 2% to 4% (v/v) in the coating solution enhanced the score of sensory parameters such as odor, color, and total acceptance of the chicken meat, especially on the last day of cold storage. The obtained results suggested ELRG-REO coatings as an effective strategy to delay the chemical and microbial deterioration of chicken meat fillets.

2.
J Biochem Mol Toxicol ; 34(10): e22559, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33034947

ABSTRACT

To date, not much study has been done to investigate the mitochondrial DNA (mtDNA) copy number as the potential biomarker for opium exposure. Here, we conducted a cross-sectional study to determine the relative mtDNA content as the potential biomarker for opium exposure. Quantitative real-time PCR was performed to investigate the mtDNA copy number variation across 205 individuals, including blood samples of 45 opium users, 41 cigarette users, 47 dual users, and 72 never users of any product. We found a significantly higher mtDNA content among the opium-only users (adjusted OR: 3.21; 95% CI: [1.34, 7.66]; P = .009) and dual users (adjusted OR: 2.64; 95% CI: [1.15, 6.1]; P = .02) compared to that in never users even after adjustment for confounding factors, age, and sex. Discordantly, analysis of mitochondrial DNA in cigarette smokers revealed an indirect association between cigarette smoking and mtDNA content although it was not statistically significant. The reason behind the increased mitochondrial DNA is unclear. The possible hypothesis is that there might be a way to compensate for the oxidative damage induced by opium consumption. Taken together, our findings indicated that the mtDNA copy number may alter during opium exposure. Since changes in the mitochondrial DNA copy number was associated with the etiology of many diseases including cancer, further investigations on the mtDNA copy number may shed light on the carcinogenicity of opium consumption and means for early detection among the populations who have been exposed to opium and its products.


Subject(s)
DNA, Mitochondrial/metabolism , Opioid-Related Disorders/metabolism , Adolescent , Adult , Aged , Biomarkers/metabolism , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Real-Time Polymerase Chain Reaction , Young Adult
3.
Carbohydr Polym ; 232: 115775, 2020 Mar 15.
Article in English | MEDLINE | ID: mdl-31952586

ABSTRACT

In the present work, we determined the structure-function relationships of basil seed gum (BSG) and whey protein isolate (WPI) mixtures at the start of soluble complex formation, maximum soluble complex formation and predominant thermodynamic incompatibility to understand BSG:WPI blends interaction behavior. Accordingly, turbidity and zeta potential were analyzed in the pH range of 2.0-7.0 and BSG:WPI ratios of 1:4, 1:6.6 and 1:9. Dynamic rheometry was used to evaluate samples at three different pHs. Additionally, dilute solution properties of BSG, WPI and their blends were studied at pH = 7.0. Independent of mixture ratio, all dispersions showed maximum interaction at pH = 5.0, the start of soluble complex formation around pH = 6.0 and thermodynamic incompatibility interaction behavior at pH = 7.0. Cole-Cole plots based on dynamic rheometry supported the Gibbs free energy change of mixtures based on intrinsic viscosity data. These results are important to create new structures from mixtures of proteins and polysaccharides.


Subject(s)
Ocimum basilicum/chemistry , Plant Gums/chemistry , Polysaccharides/chemistry , Seeds/chemistry , Whey Proteins/chemistry , Hydrogen-Ion Concentration , Particle Size , Surface Properties , Whey Proteins/isolation & purification
4.
Int J Biol Macromol ; 151: 1139-1153, 2020 May 15.
Article in English | MEDLINE | ID: mdl-31747568

ABSTRACT

Some rheological, thermodynamic and functional properties of selected hydrocolloids (xanthan gum-cress seed gum (XG-CSG)) blends at different ratios (1-0, 3-1, 1-1, 1-3, 0-1) were characterized to understand physically the biopolymers interaction and networks. XG showed a greater rigidity (elastic modulus, G'LVE = 58.60 Pa), total structural strength (complex modulus, G*LVE = 70.69 Pa), yield stress (limiting value of stress, τL = 7.58 Pa), emulsion capacity (EC = 6.78%) and foam stability (FC = 18.92%) than CSG (G'LVE = 7.05 Pa, G*LVE = 8.53 Pa, τL = 1.44 Pa, EC = 86.48% and FC = 14.98%), respectively. Among blends, 3-1 XG-CSG showed the highest G*LVE, foaming stability (FS) and the extent of recovery (Rr%). The results were summarized using the clustering technique and principal component analyses. The coefficient of the interaction of some parameters, Cole-Cole plots and Gibbs free energy changes (ΔG) of predisturbed and intact networks were investigated. In samples with an intact network, greater compatibility directly related to the extent of synergistic interaction, while in predisturbed samples, the lower compatibility directly related to the extent of synergistic interaction. Although all blends were highly incompatible with antagonistic behavior, 1-1 XG-CSG showed the lowest incompatibility (ΔG = 8028.60 J/mol) among samples with intact structure, while at disrupted state, 1-3 XG-CSG showed the lowest incompatibility (ΔG = 158.6 J/mol).


Subject(s)
Chemical Phenomena , Colloids/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Algorithms , Biopolymers/analysis , Emulsifying Agents/chemistry , Emulsions , Models, Theoretical , Rheology , Thermodynamics , Viscosity
5.
J Texture Stud ; 50(6): 520-538, 2019 12.
Article in English | MEDLINE | ID: mdl-31226217

ABSTRACT

Dynamic rheological and mechanical properties of seven commercial (xanthan [XG], guar [GG], high methoxylated pectin [HMP], κ-carrageenan [κ-Car], agar [AG], alginate [ALG], and carboxymethylcellulose [CMC]) and four emerging hydrocolloids (basil seed gum [BSG], sage seed gum [SSG], Balangu-Shirazi seed gum [BSSG], and cress seed gum [CSG]) were investigated and the classification of the hydrocolloids were carried out based on them. AG belonged to the first class with 0.81 membership function (MF), κ-Car and HMP grouped in the second class with 0.68 and 0.71 MFs, respectively, XG, BSG, and SSG were depended to the third class with 0.61-0.70 MFs, finally, CMC, GG, BSSG, ALG, and CSG related to the fourth class, as the most populated class, with MF > 0.61. The first class contained the highest amount of hardness parameter (43.40 ± 2.76 g), the second class included the highest pseudoplasticity parameter (shear-thinning ratio = -0.54 ± 0.03) and relaxation time (66.25 ± 2.61 s) and the fourth cluster comprised the highest frequency dependency of viscous modulus (exponent of power-law model for viscous modulus vs. frequency = 0.30 ± 0.05). In addition, the results of this study showed that there was a distinct relationship between nonlinear harmonics in the stress wave and fundamental characteristics of hydrogel networks. The investigation of the rheo-mechanical properties of biopolymers in large deformation under shear and normal forces can have an important role in the prediction of the behavior of the material in real processes and application conditions, especially in the food industry. Due to the inconvenience of large deformation mechanical tests, such as Weissenberg effect, the complication of the results analyzing and sampling difficulty of semi-dilute samples; herein, we determined the correlation between large deformation (LAOS and texture analysis) and small deformation (SAOS) tests properties. The studied rheo-mechanical parameters showed high correlation with the four mentioned network parameters (more than 65% similarity index). Using these results, other scientists could rationally design the experiments and avoid experiments with similar parameters.


Subject(s)
Colloids/chemistry , Food Handling , Shear Strength , Brassicaceae/chemistry , Carrageenan/chemistry , Cyamopsis/chemistry , Hydrogels , Ocimum basilicum/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Rheology , Salvia officinalis/chemistry , Seeds/chemistry , Viscosity
6.
J Texture Stud ; 50(6): 493-507, 2019 12.
Article in English | MEDLINE | ID: mdl-31172527

ABSTRACT

Herein, oscillatory rheological measurements were performed to study the interaction behavior of xanthan gum-sage seed gum blends at different ratios (SSG-XG: 1-0, 3-1, 1-1, 1-3, 0-1), from the dynamic viscosity behavior, relaxation spectrum, fracture properties, network parameters, and thermodynamic points of view at the temperature range of 10-90°C. Then, the coefficient of the interaction of four parameters, which were obtained from the clustering technique and Han curves, were used to investigate the interaction behavior quantitatively. At 90°C, SSG showed 2.01 extent of loss modulus overshoot, which was the highest value among different gum dispersions at different temperatures, while XG showed strain softening behavior. At 10 and 90°C, SSG and 1-1 SSG-XG showed the highest spreadability reflected by the slope of loss tangent after flow point stress (tan δAF ) of 0.52 and 0.40, respectively. The high values of ψ parameter, which represented the Gibbs free energy change, of both 1-3 and 3-1 SSG-XG blends and the lowest entropy value of 1-3 SSG-XG, suggested that the role of entropy change in incompatibility behavior of 1-3 SSG-XG was higher than that of 3-1 SSG-XG blend. With the increase in temperature from 10 to 70°C, the XG Euclidean distance from SSG decreased, while it increased from 70 to 90°C and showed the highest Euclidean distance with XG at 10°C (3.92) and 90°C (4.05). Interaction coefficients and Han curves results showed that all blends were incompatible with the lowest antagonistic behavior for 1-1 SSG-XG dispersion at 50°C. Often, a mixture of hydrocolloids, especially xanthan gum and a galactomannan, are employed in processed foods to modify their rheological properties and cut the cost. The synergistic/non-synergistic effect of biopolymers mixture, which is invaluable from the practical and economical points of view, seems to be mainly induced by their thermodynamic status of interaction. Our former study showed that the thermodynamic indices of mixing could be probed by mechanical parameters. On the other hands, we found that the mechanical properties of materials are highly temperature dependent. Therefore, in this study, to better investigate the effect of temperature on the biopolymers interaction, first we classified all the thermodynamic and mechanical properties (relaxation spectrum, fracture properties, and network parameters) of hydrocolloids into four classes, then one parameter was selected randomly from each class. The selected parameters were employed to investigate the synergistic/non-synergistic effect at all temperature ranges by determining the interaction coefficient and decide on the best interaction temperature.


Subject(s)
Biopolymers/chemistry , Plant Gums/chemistry , Rheology , Thermodynamics , Colloids , Galactose/analogs & derivatives , Mannans/chemistry , Models, Biological , Polysaccharides, Bacterial , Salvia officinalis/chemistry , Seeds , Temperature , Viscosity
7.
Int J Biol Macromol ; 124: 270-281, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30481532

ABSTRACT

In this study, viscoelastic properties and textural profile analysis of starches from two canary seed varieties (CDC Maria and C05041) were compared with wheat starch. Based on amplitude sweep, the limiting strain values were 5.7%, 5.4% and 16.3% for CDC Maria, C05041, and wheat starch gels, respectively. The yield stress values at the linear viscoelastic limit (τy) and flow point (τf) of wheat starch (25.4 & 35.5 Pa, respectively) were higher than CDC Maria (14.3 and 24.2 Pa, respectively) and C05041 (6.5 and 9.1 Pa, respectively) starches. On the other hand, canary seed starches showed higher modulus at flow point (Gf, 51.2-108.4 Pa) than wheat starch (41.2 Pa). In frequency sweep, canary seed starch gels showed lower frequency dependency (n' = 0.033-0.009) in comparison with wheat starch gel (n' = 0.063), categorizing the samples between weak and strong gels. On the basis of creep parameters of Burger model, CSSs illustrated more elastic behavior than wheat starch. The results of dynamic temperature sweep showed that canary seed starches exhibited higher peak, final, breakdown and setback viscosities in compare to wheat starch. Textural profile analysis provided the values of hardness (32-101 g), adhesiveness (0.03-0.17 mJ), cohesiveness (0.60-0.97) and gumminess (24.7-83.3 g) for the gels (15% w/w).


Subject(s)
Gels/chemistry , Phalaris/chemistry , Starch/chemistry , Viscosity , Hardness , Rheology , Seeds/chemistry , Temperature , Triticum/chemistry
8.
J Texture Stud ; 49(6): 619-638, 2018 12.
Article in English | MEDLINE | ID: mdl-30246503

ABSTRACT

In this study, we proposed an objective classification of seven commercial hydrocolloids and four novel hydrocolloids. Total of 74 rheological parameters was generated by steady (flow behavior, hysteresis loop, single shear decay, in-shear structural recovery experiments), dynamic (strain sweep and frequency sweep tests), and transient (creep/recovery and stress relaxation) shear measurements. Subsequently, the parameters were classified into seven categories with more than 60% similarity indexes in each group using agglomerative hierarchical clustering based on those properties related to the number of linkage, strength of linkage, distance of linkage, rupture and flow, rate of destruction, the extent of destruction, and the state of destructured samples in the absence of flow field. Fuzzy c-means classifier used to extract patterns for each class. Our results correspond to four different classes; κ-carrageenan and agar gum were categorized in the first class, high methoxyl pectin, xanthan, sage seed gum and basil seed gum in the second class, alginate gum and Balangu-Shirazi seed gum in the third class, and guar gum, cress seed gum and carboxymethyl cellulose in the fourth class. Using this classification technique, complete rheological patterns can be extracted for each class. This classification provides a map for other researchers to rationally design the best test type which could describe adequately different properties of materials and avoid experiments with a similar type of parameters. The main reason for the frequent use of hydrocolloids in various industries is their ability to modify the rheology. A lot of works have been done to study the rheological behavior of many hydrocolloids in model and food systems. As there is still demand for new sources of hydrocolloids with more specific functionality in foods, probing the similarities among commercial and emerging hydrocolloids could help us to rationally design structural features in different formulations, besides gives insight into the structure-function relationship between them. This object could be attained by clustering, a part of the pattern recognition theory. Contrary to the traditional clustering methods, in which the membership of a product is exclusive for only a class, in constraint clustering by fuzzy logic methods, a partial membership can be shared by two or more classes. In this way, using the fuzzy logic clustering method, we clustered a number of commercial and novel hydrocolloids based on the steady, transient, and dynamic shear rheological properties and found a specific pattern among them. PRACTICAL APPLICATIONS: The main reason for the frequent use of hydrocolloids in various industries is their ability to modify the rheology. A lot of works have been done to study the rheological behavior of many hydrocolloids in model and food systems. As there is still demand for new sources of hydrocolloids with more specific functionality in foods, probing the similarities among commercial and emerging hydrocolloids could help us to rationally design structural features in different formulations, besides gives insight into the structure-function relationship between them. This object could be attained by clustering, a part of the pattern recognition theory. Contrary to the traditional clustering methods, in which the membership of a product is exclusive for only a class, in constraint clustering by fuzzy logic methods, a partial membership can be shared by two or more classes. In this way, using the fuzzy logic clustering method, we clustered a number of commercial and novel hydrocolloids based on the steady, transient, and dynamic shear rheological properties and found a specific pattern among them.


Subject(s)
Colloids/chemistry , Food Technology , Plant Gums/chemistry , Humans , Rheology , Viscosity
9.
Food Res Int ; 108: 136-143, 2018 06.
Article in English | MEDLINE | ID: mdl-29735042

ABSTRACT

In this study, the effect of natural macromolecules as carrier agents on the biological activity of nano-encapsulated Bene hull polyphenols (Pistacia atlantica subsp. Mutica) through W/O/W emulsions was evaluated. The W/O microemulsions as primary emulsions and a complex of soy protein isolate and basil seed gum (SPI-BSG), whey protein isolate and basil seed gum (WPI-BSG) and also Hi-Cap 100 in the outer aqueous phase were used to produce W/O/W nano-emulsions. Z-average size of emulsions stabilized by Hi-Cap, WPI-BSG, and SPI-BSG was 318, 736.9 and 1918 nm, respectively. The encapsulation efficiency of polyphenols for powders produced by Hi-Cap, WPI-BSG, and SPI-BSG was 95.25, 90.9 and 92.88%, respectively, which was decreased to 72.47, 67.12 and 64.44% after 6 weeks storage at 30 °C. The antioxidant activity of encapsulated polyphenols at 100, 200 and 300 ppm was measured in oil by peroxide and p-anisidine values during storage and was compared to non-encapsulated extract and synthetic antioxidant. Results showed oxidative alterations in oils containing encapsulated polyphenols was lower than unencapsulated form, which among them capsules produced by SPI-BSG exhibited higher antioxidant effects due to the better gradual release. Generally, the higher antioxidant potential was achieved with increased solubility and controlled release of polyphenols through their nano-encapsulation.


Subject(s)
Antioxidants/chemistry , Food Handling/methods , Nanoparticles , Ocimum basilicum/chemistry , Pistacia/chemistry , Plant Gums/chemistry , Polyphenols/chemistry , Seeds/chemistry , Soybean Oil/chemistry , Soybean Proteins/chemistry , Water/chemistry , Whey Proteins/chemistry , Antioxidants/isolation & purification , Emulsions , Food Analysis/methods , Food Storage , Nanotechnology , Oxidation-Reduction , Particle Size , Plant Gums/isolation & purification , Polyphenols/isolation & purification , Time Factors
10.
J Texture Stud ; 48(5): 470-484, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28967216

ABSTRACT

The viscoelastic (transient and dynamic) and time-dependent rheological behaviors of XG (xanthan gum), SSG (sage seed gum) and their blends at various ratios (1-3, 1-1, and 3-1 SSG-XG) and temperatures (10, 30, and 50C) were investigated using creep and recovery analyses. The creep compliance was converted to stress relaxation data; then, the structural kinetic model satisfactorily fitted the time-dependent relaxation modulus. Furthermore, dynamic rheology of mixtures was investigated using creep analyses. The most important contribution of the Maxwell spring to deformation (53.51%), was that corresponding to the SSG at 50C and the most important contribution of the Maxwell dashpot to the maximum deformation, were those corresponding to the XG (61.44%) and 1-3 SSG-XG (58.91%) samples both at 50C. The breakdown rate constant ( α) of the crosslinked gum structure in SSG and 3-1 SSG-XG under the application of external shear stress increases with temperature from 10 to 50C in the range of 0.14-0.32 (1/s) and 0.14-0.24 (1/s), respectively, whereas other dispersions showed the reverse trend. Among all dispersions, only XG and 1-3 SSG-XG demonstrated crossover frequency at 9.95 and 31.47 rad/s, respectively, at 50C, indicative of the lowest entanglement density for 1-3 SSG-XG. The greatest interaction between SSG and XG occurred for 3-1 ratio at 50C, which was confirmed by the Han curves. PRACTICAL APPLICATIONS: Hydrocolloid blends, particularly those consisting of xanthan gum and a galactomannan from new source can provide a range of attractive textural properties. Rheological studies contribute to the description of the molecular structure and prediction of the structural changes during their manufacturing processes. Sage seed gum (SSG), as a polyelectrolyte galactomannan, has a great potential to exert stabilizing, thickening, gelling and binding properties in food, cosmetics, and pharmaceutical systems. Therefore, we elaborate the interactions between SSG and xanthan gum and also the effect of temperature using transient measurements. In this way, we show that the viscoelastic (transient and dynamic) and time-dependent rheological behaviors may be investigated using single creep/recovery tests. This new insight into transient measurements is useful to characterize the interaction behavior of similar biopolymers blends.


Subject(s)
Galactans/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Rheology , Temperature , Chemical Phenomena , Cross-Linking Reagents , Food Additives/chemistry , Linear Models , Rheology/methods , Thermodynamics , Viscosity
11.
Int J Biol Macromol ; 97: 752-760, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28111297

ABSTRACT

Estimation of the amounts of glucose release (AGR) during gastrointestinal digestion can be useful to identify food of potential use in the diet of individuals with diabetes. In this work, adaptive neuro-fuzzy inference system (ANFIS), genetic algorithm-artificial neural network (GA-ANN) and group method of data handling (GMDH) models were applied to estimate the AGR from native (NWS), cross-linked (CLWS) and hydroxypropylated wheat starch (HPWS) gels during digestion under simulated gastrointestinal conditions. The GA-ANN and ANFIS were fed with 3 inputs of digestion time (1-120min), gel volume (7.5 and 15ml) and concentration (8 and 12%, w/w) for prediction of the AGR. The developed ANFIS predictions were close to the experimental data (r=0.977-0.996 and RMSE=0.225-0.619). The optimized GA-ANN, which included 6-7 hidden neurons, predicted the AGR with a good precision (r=0.984-0.993 and RMSE=0.338-0.588). Also, a three layers GMDH model with 3 neurons accurately predicted the AGR (r=0.979-0.986 and RMSE=0.339-0.443). Sensitivity analysis data demonstrated that the gel concentration was the most sensitive factor for prediction of the AGR. The results dedicated that the AGR will be accurately predictable through such soft computing methods providing less computational cost and time.


Subject(s)
Gastrointestinal Tract/metabolism , Glucose/chemistry , Models, Biological , Neural Networks, Computer , Starch/chemistry , Starch/metabolism , Triticum/chemistry , Digestion , Gels
12.
Int J Biol Macromol ; 93(Pt A): 623-629, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27620465

ABSTRACT

Hydrocolloid interactions with solvent/cosolutes play a vital role in the resolution of their functional properties. Basil seed gum (BSG) is a plant-derived hydrocolloid which has been found many applications in food formulations as stabilizer, emulsifier, thickener and gelling agents. Sucrose and lactose are the most effective sugars in textural and sensorial properties of bakery and dairy products which adding them to solutions containing hydrocolloids can be helpful to approach a proper formula. In this paper, the effect of temperature (25-65°C), sucrose (10, 20, 30 and 40%) and lactose (5, 10 and 15%) were investigated through some molecular parameters of BSG. Results revealed high flexible chain (665.35), intrinsic viscosity (11.38 dl/g) and hydrogel content (73%) of BSG, which may be attributed to some extent by its high molecular weight (1.73×106Da). The density and intrinsic viscosity of BSG were diminished by growing temperature from 25 to 55°C. Among five models, which were applied to estimate intrinsic viscosity, Higiro-2 was the most suitable model at varying temperatures and cosolutes concentrations. The sugars showed a significant effect on the molecular parameters of BSG such as swollen specific volume, shape function, hydration parameter, and coil dimensions. The sugars showed more impact on the [η] of BSG and its molecular parameters than that of temperature. However, lactose had a more prominent effect on the BSG dimensions than that of sucrose, which can be related to its molecular conformation and spatial orientation. It is feasible to make a proper formula by BSG and explain some phenomena in its applications in food and pharmaceutical systems.


Subject(s)
Lactose/chemistry , Ocimum basilicum/chemistry , Plant Gums/chemistry , Seeds/chemistry , Sucrose/chemistry , Temperature , Carbohydrate Conformation , Solutions , Viscosity
13.
Int J Biol Macromol ; 91: 1018-24, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27316768

ABSTRACT

The rheological properties of food hydrocolloids are remarkably influenced by the quality of solvent/cosolutes in a food system. In this work, the steady shear flow behavior of sage seed gum (SSG, 0.5% w/w) at the presence of different levels of salts (KCl & MgCl2, 0-100mM) and sugars (sucrose, lactose & glucose, 0-6% w/w) was studied. It was found that the rheological properties of SSG were affected by the type of sugars and salts and their concentrations as well. Synergistic interaction was observed between SSG and sugars which enhanced the viscosity of gum solutions, while salts addition diminished the viscosity. SSG solutions exhibited a shear thinning behavior at all conditions tested. Various time-independent rheological models were used to fit the shear stress-shear rate data, although the Herschel-Bulkley (R(2)=0.994-0.999) and Sisko (R(2)=0.995-0.999) models showed the best results to describe the flow behavior of SSG. In the presence of salts, the yield stress (τ0), consistency coefficient (k), and flow behavior index (n) values decreased. The k and τ0 values enhanced and the n value lowered in the presence of sugars. Divalent cations of Mg(2+) and sucrose roughly showed more effect on rheological parameters than others.


Subject(s)
Carbohydrates/pharmacology , Plant Gums/chemistry , Rheology/drug effects , Salts/pharmacology , Salvia officinalis/chemistry , Seeds/chemistry , Shear Strength/drug effects , Solutions , Time Factors , Viscosity/drug effects
14.
Int J Biol Macromol ; 87: 123-9, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26902890

ABSTRACT

Dilute solution properties of an unknown starch are important to understand its performance and applications in food and non-food industries. In this paper, rheological and molecular properties (intrinsic viscosity, molecular weight, shape factor, voluminosity, conformation and coil overlap parameters) of the starches from two hairless canary seed varieties (CO5041 & CDC Maria) developed for food use were evaluated in the dilute regime (Starch dispersions in DMSO (0.5g/dl)) and compared with wheat starch (WS). The results showed that Higiro model is the best among five applied models for intrinsic viscosity determination of canary seed starch (CSS) and WS on the basis of coefficient of determination (R(2)) and root mean square error (RMSE). WS sample showed higher intrinsic viscosity value (1.670dl/g) in comparison to CSS samples (1.325-1.397dl/g). Berry number and the slope of master curve demonstrated that CSS and WS samples were in dilute domain without entanglement occurrence. The shape factor suggested spherical and ellipsoidal structure for CO5041 starch and ellipsoidal for CDC Maria starch and WS. The molecular weight, coil radius and coil volume of CSSs were smaller than WS. The behavior and molecular characterization of canary seed starch showed its unique properties compared with wheat starch.


Subject(s)
Phalaris/chemistry , Seeds/chemistry , Starch/chemistry , Triticum/chemistry , Carbohydrate Conformation , Molecular Weight , Rheology , Solutions , Viscosity
15.
J Food Sci Technol ; 53(1): 370-80, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26787956

ABSTRACT

Roasting is an important step in the processing of pistachio nuts. The effect of hot air roasting temperature (90, 120 and 150 °C), time (20, 35 and 50 min) and air velocity (0.5, 1.5 and 2.5 m/s) on textural and sensory characteristics of pistachio nuts and kernels were investigated. The results showed that increasing the roasting temperature decreased the fracture force (82-25.54 N), instrumental hardness (82.76-37.59 N), apparent modulus of elasticity (47-21.22 N/s), compressive energy (280.73-101.18 N.s) and increased amount of bitterness (1-2.5) and the hardness score (6-8.40) of pistachio kernels. Higher roasting time improved the flavor of samples. The results of the consumer test showed that the roasted pistachio kernels have good acceptability for flavor (score 5.83-8.40), color (score 7.20-8.40) and hardness (score 6-8.40) acceptance. Moreover, Partial Least Square (PLS) analysis of instrumental and sensory data provided important information for the correlation of objective and subjective properties. The univariate analysis showed that over 93.87 % of the variation in sensory hardness and almost 87 % of the variation in sensory acceptability could be explained by instrumental texture properties.

16.
J Food Sci Technol ; 52(12): 8377-82, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26604418

ABSTRACT

In this study, some physical properties (principal dimensions, mean diameters, sphericity, area, density and electrical conductivity) of split chickpea were measured as function of soaking time (up to 360 min) and temperature (25-65 °C). Initially, the water absorption rate was high and then it showed a progressive decrease at all temperatures, whereas solid loss exhibited a power function of temperature (P < 0.05). The Peleg model was predicted well the kinetic of split chickpea soaking. No significant difference (P < 0.05) was observed in Peleg rate constant (K1) and Peleg capacity constant (K2) at all temperatures except for K1 at 25 °C. The discrepancy for K1 was in relation to permeability characteristics of split chickpea at temperature of 25 °C. As temperature increased from 25 to 65 °C, the K1 value decreased from 0.04620 to 0.00945 g h(-1), whereas the K2 value increased from 0.08597 to 0.11320 g(-1). Plot for K1 exhibited a slope changes around 45 °C corresponding to gelatinization temperature of split chickpeas. The effect of temperature and time on physical properties of split chickpea during soaking was monitored by regression equations. It was concluded that physical properties of split chickpea affected by its water absorption especially at higher temperatures.

17.
Int J Biol Macromol ; 81: 418-26, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26277752

ABSTRACT

The objective of this study was to investigate the effect of various temperatures (25-65°C) on some dilute solution properties of Alyssum homolocarpum seed gum (AHSG) as a novel potential source of hydrocolloid. Monosaccharide composition, FTIR analysis and molecular parameters were determined to provide more structural information. The results indicated that AHSG had a low molecular weight (3.66×10(5)Da), medium intrinsic viscosity (18.34dl/g) at 25°C, relatively flexible chain with a chain flexibility parameter of 618.54, and activation energy of 0.51×10(7)J/kgmol. With rise in temperature from 25 to 55°C, the intrinsic viscosity decreased as well as coil radius and volume of AHSG. The shape factor of AHSG macromolecule was spherical at all temperatures. The electrostatic interaction and particle size of AHSG solution were -25.81mV (at neutral pH) and 225.36nm, respectively. The results revealed that AHSG had high total sugar content (85.33%), small amount of uronic acids (5.63%) and it is likely a galactan-type polysaccharide. The FTIR spectra showed that AHSG behaved like a typical polyelectrolyte because of the presence of carboxyl and hydroxyl groups.


Subject(s)
Brassicaceae/chemistry , Plant Gums/chemistry , Seeds/chemistry , Carbohydrates/chemistry , Molecular Weight , Spectroscopy, Fourier Transform Infrared , Temperature , Viscosity
18.
Int J Biol Macromol ; 80: 424-30, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26143122

ABSTRACT

The seeds of Lepidium sativum (garden cress) were selected as a new hydrocolloid source to fabricate cress seed gum nanoparticles (CSGN) by the desolvation method. The intrinsic viscosity of the CSGN solutions was measured to evaluate the conformational differences of the CSG resulted by the various production conditions. The intrinsic viscosity of CSGN solutions was estimated by using various models, i.e. Huggins, Kraemer, Tanglertpaibul-Rao and Higiro, and then the intrinsic viscosity was an objective function aimed at optimizing the conditions for the solubilization of CSG nanoparticles by the response surface method. The results indicated that among the conditions for the preparation of nanoparticles, acetone and gum concentrations had significant effects on the intrinsic viscosity of nanoparticles. Hereby, CSG served as a source of anionic polyelectrolyte molecules in dilute solutions with acetone-water mixtures. This compound goes on to display a coil-globule transition above a certain threshold of acetone.


Subject(s)
Nanoparticles/chemistry , Plant Gums/chemistry , Acetone/chemistry , Brassicaceae , Nanoparticles/ultrastructure , Seeds , Solutions , Solvents , Viscosity
19.
Food Funct ; 6(9): 3126-34, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26220451

ABSTRACT

The digestibility and estimated glycemic indices (GI) of native (NWS), cross-linked (CLWS) and hydroxypropylated wheat starches (HPWS) were obtained by in vitro enzymatic hydrolysis. The resistant starch (RS) content and GI were found to be 6.59 and 93.13 for NWS, 7.57 and 92.20 for CLWS, and 13.15 and 89.04 for HPWS, respectively. The amounts of glucose release for CLWS were approximately 6-11%, and for HPWS were 16-19%, lower than that for NWS after digestion under simulated intestinal conditions (SIC). The linear and two-term exponential models were fitted well to the experimental glucose release data under simulated gastric conditions (SGC) and SIC, respectively (R(2) = 0.858-0.991). After digestion under SIC, the consistency coefficient (k) values drastically decreased (73.02-90.27%), while the flow behavior index (n) increased (155.56-363.64%). Therefore, the amounts of glucose release can be controlled by manipulating the structure of native starches using chemical modifications such as cross-linking and hydroxypropylation.


Subject(s)
Gastrointestinal Tract/metabolism , Starch/metabolism , Triticum/metabolism , Digestion , Glucose/metabolism , Glycemic Index , Humans , In Vitro Techniques , Models, Biological , Molecular Structure , Starch/chemistry , Triticum/chemistry
20.
J Food Sci Technol ; 52(5): 2958-65, 2015 May.
Article in English | MEDLINE | ID: mdl-25892796

ABSTRACT

The development of non-destructive methods for the evaluation of food properties has important advantages for the food processing industries. So, the aim of this study was to evaluate the effects of frying temperature (150, 170, and 190 °C) and time (0.5, 1.5, 2.5, 3.5 and 4.5 min) on image properties (L*, a* and b*, fractal dimension, correlation, entropy, contrast and homogeneity) of pellet snacks. Textures were computed separately for eight channels (RGB, R, G, B, U, V, H and S). Enhancing the frying time from 0.5 min to 2.5 min increased the fractal dimension; but its increase from 2.5 min to 4.5 min could not expand the samples. Then, the highest volume of pellet snacks was observed at 2.5 min. Features derived from the image texture contained better information than color features. The best result was for U channel which showed that increasing the frying time increased the contrast, entropy and correlation. Developing the frying temperature up to 170 °C decreased contrast, entropy and correlation of images; however these factors were increased when frying temperature was 190 °C. These results were invert for homogeneity.

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