Rheology of Ice Cream Mix Flavored with Black Tea or Herbal Teas and Effect of Flavoring on the Sensory Properties of Ice Cream

Rheological characteristics and physicochemical properties of ice cream mix flavored with black tea or some herbal teas and sensory profile of flavored ice cream was investigated. In this respect, black tea and three different herbal tea samples (sage, chamomile, and linden) were used to produce a new ice cream formulation. Some physicochemical properties and sensory characteristics of samples were determined. Total phenolic content of ice cream samples increased with the use of tea or herbal teas and it was in the range of 123.37-415.20 mg kg(-1). Incorporation of black tea and herbal tea except chamomile decreased the sensory scores of ice cream compared to control sample. The apparent viscosities of samples were measured as a function of shear rate and consistency coefficient and flow behavior index were calculated by using power law model. All ice cream mix samples showed non-Newtonian pseudoplastic behavior. The apparent viscosities of ice cream mixes treated with no tea at the shear rate of 50 s(-1) were 1.13, 0.91, and 0.76 Pa s at 10, 20, and 30 A degrees C, respectively. The activation energy for the viscosity change of the samples ranged between 10.87-20.25 J mol(-1) at 50 s(-1)

Rheological and some physicochemical characteristics of selected Turkish honeys

In this study, some physicochemical properties and rheological characteristics of four Turkish honey samples were determined. Moisture content, ash content, pH and water activity of the samples were determined using standard procedures. The rheological properties of honeys were investigated using a controlled stress rheometer equipped with a plate-plate configuration over a temperature range of 10-40C. There was no difference among the honey varieties in terms of water activity values. Rheological results indicated that all samples exhibited Newtonian flow behavior. The viscosity varied between 2.8 and 101 Pa.s according to honey type and temperature. Temperature dependence of viscosity was adequately described by the Arrhenius relationship, with determination coefficients of 0.990 or greater. The calculated activation energy of the honey samples ranged from 63.4 to 78.5 kJ/mol. Viscosity of citrus honey, with the lowest activation energy, was found to be less sensitive to temperature change compared with other honey varieties

Effect of temperature on rheological characteristics of molasses: Modeling of apparent viscosity using Adaptive Neuro-Fuzzy Inference System (ANFIS)

In this study, the effect of temperature on the rheological characteristics of apricot and date molasses was studied separately. Rheological characteristics of both molasses were evaluated in the shear rate range of 0.1-100 s(-1) different temperatures (10-40 degrees C). Power law model was used for the calculation of flow behavior index and consistency coefficients of molasses. Consistency coefficients of apricot and date molasses were in the range of 5.408-39.905 Pa s(n) and 0.910-2.852 Pa s(n), respectively. Molasses samples showed a non-Newtonian flow behavior. The effect of temperature on apparent viscosity was described by Arrhenius equation and calculated activation energy at the shear rate of 54.2 s(-1) was 41.42 and 38.19 kJ/mol for apricot and date molasses, respectively. An efficient predictive model for apparent viscosity values of molasses was constructed using Adaptive Neuro - Fuzzy Inference System (ANFIS) and this model showed satisfactory prediction with high coefficient of determination (0.979-0.999) and low root mean squared error (0.12-0.46). (C) 2011 Elsevier Ltd. All rights reserved

Rheological Characterization of Binary Combination of Gleditsia triacanthos Gum and Tapioca Starch

In the current study, Gleditsia triacanthos gum and tapioca starch were combined and rheological characterization of the binary mixture was performed. Gleditsia triacanthos gum at four different concentrations (0.1, 0.4, 0.7, and 1.0%, w/v) was mixed with tapioca starch at a constant level (2.5%, w/v). Steady shear and dynamic shear rheological properties of samples were determined using a stress/strain controlled rheometer at a constant temperature (25oC). Oswald de Waele model was used to describe the shear rate effect on apparent viscosity values of the samples. Increase in the Gleditsia triacanthos level increased the apparent viscosity and consistency coefficient of the samples. Similarly, dynamic shear rheological parameters of the samples increased with the increase of Gleditsia triacanthos gum. The concentration of 0.7% for Gleditsia triacanthos gum was determined to be cross point for the liquid-solid phase. From this level, the elastic behavior became more dominant compared to viscous behavior because tangent delta was equal to one in this concentration. To describe the effect of Gleditsia triacanthos level on the studied rheological parameters, the Power law and exponential type models were used.In the current study, Gleditsia triacanthos gum and tapioca starch were combined and rheological characterization of the binary mixture was performed. Gleditsia triacanthos gum at four different concentrations (0.1, 0.4, 0.7, and 1.0%, w/v) was mixed with tapioca starch at a constant level (2.5%, w/v). Steady shear and dynamic shear rheological properties of samples were determined using a stress/strain controlled rheometer at a constant temperature (25C). Oswald de Waele model was used to describe the shear rate effect on apparent viscosity values of the samples. Increase in the Gleditsia triacanthos level increased the apparent viscosity and consistency coefficient of the samples. Similarly, dynamic shear rheological parameters of the samples increased with the increase of Gleditsia triacanthos gum. The concentration of 0.7% for Gleditsia triacanthos gum was determined to be cross point for the liquid-solid phase. From this level, the elastic behavior became more dominant compared to viscous behavior because tangent delta was equal to one in this concentration. To describe the effect of Gleditsia triacanthos level on the studied rheological parameters, the Power law and exponential type models were used.</p

Enrichment of wheat chips with omega-3 fatty acid by flaxseed addition: Textural and some physicochemical properties

In the present study, wheat chips enriched with flaxseed flour were produced and response surface methodology was used for the studying the simultaneous effects of flaxseed level (10-20%), frying temperature (160-180 degrees C) and frying time (40-60 s) on some physicochemical, textural and sensorial properties and fatty acid composition of wheat chips. Ridge analysis was conducted to determine the optimum levels of processing variables. Predictive regression equations with adequate coefficients of determination (R-2 >= 0.705) to explain the effect of processing variables were constructed. Addition of flaxseed flour increased the dry matter and protein content of samples and increase of frying temperature decreased the hardness values of wheat chips samples. Increment in flaxseed level provided an increase in unsaturated fatty acid content namely omega-3 fatty acids of wheat chips samples. Overall acceptability of chips increased with the increase of frying temperature. Ridge analysis showed that maximum taste score would be at flaxseed level = 10%, frying temperature = 180 degrees C and frying time = 50 s. (C) 2013 Elsevier Ltd. All rights reserved