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In this study, the flow behavior and creep parameters of saffron desserts containing gum tragacanth combinations of three species were modeled by the mixture design approach. Flow behavior and creep-recovery experiments were performed and models were predicted for apparent viscosity, consistency index, flow index, instantaneous compliance, and viscoelastic compliance. Five representative samples regarding the range of apparent viscosity at the shear rate of 50 s-1 were subjected to sensory evaluation. According to rheological measurements, the addition of GT species of A. gossypinus led to the production of a dessert with a strong structure. Then, two samples with the highest consistency index and the lowest creep parameters were compared with two commercial saffron desserts. The results revealed that the overall acceptance of the two selected samples [containing 4% (w/w) A. gossypinus or 2.66% (w/w) A. gossypinus and 1.33% (w/w) A. fluccosus] was similar to those of the two commercial samples.

In addition to the nutrients, acorn fruits contain a large amount of Polyphenolic compounds. For this reason, acorn can be considered as a suitable raw material for making bread and sweets. The use of acorn flour in food products leads to enhancing their nutritional value, creating added value for this forest fruit and then, helps to preserve oak lands and forests. Therefore, the purpose of this research was to enrich bread using acorn flour. So, the effect of replacing 10 -30% acorn flour with wheat flour along with 1 -4% gluten on the quality characteristics of the produced bread was investigated. Optimization of bread formula was done based on response surface method. The results showed that the use of acorn flour leads to an increase in hardness in bread and the addition of gluten moderates part of this effect. The initial hardness and specific volume of the samples were obtained in the range of 7.31 to 9.1 N and 2.94 to 3.7 cm3/g corresponding to the samples with the lowest and highest amount of acorn flour. The results of image processing of bread crumb showed that with the increase in the percentage of acorn flour usage, the percentage of porosity decreased significantly, although the porosity value was increased by the addition of gluten (p<0.05). It was also found that the addition of acorn flour caused a decrease in the brightness of the crumb and crust of the bread. Finally, the optimized formula with 10% acorn flour and 4% gluten was more accepted by the panel taste, with a score of 4.83, compared to the sample without acorn flour, which scored 4.08. Therefore, it is possible to remove the disadvantages of bread containing oak flour by adding gluten and even achieve bread with a more favorable overall acceptance than wheat bread. [ABSTRACT FROM AUTHOR]

Abstract: The effect of voltage gradient, pH and S/L ratio during ohmic heating up to 90 °C on the heating rate, system performance coefficients (SPCs), yield, and quality of pectin was investigated. The results showed that the rate of heating was increased with increasing of voltage gradient (from 5 to 30 V/cm) and decreased with decreasing of pH (from 4 to 1.5). With increasing of voltage gradient and decreasing of pH and S/L ratio, SPC was increased and the highest SPC was 84.4%. The yield of pectin was increased sharply from 1.17 to 10.69 g/100 g d.m. by decreasing of pH from 4 to 1.5. Finally, the highest SPC and yield of pectin with good quality (high DE and galacturonic acid) were obtained at the voltage gradient of 30 V/cm, pH of 1.5 and S/L ratio of 1:20 g/ml. Practical applications: Ohmic heating technology has a good potential to extract some components from plant waste because it heats the material rapidly with high energy efficiency (SPC) in comparison to the conventional heating, therefore it can be an appropriate alternative method for extraction of pectin industrially. In addition to obtaining the highest pectin with good quality, determination of ohmic heating rate (or time of heating) and SPC at different conditions is necessary to design the industrial ohmic extraction. [ABSTRACT FROM AUTHOR]