No abstract

The influence of glycerol, sorbitol, maltitol and propylene glycol on shelf life and quality of Barbari, Iranian flat bread, fortified with soy flour, was examined. Effects of different levels of polyols (0, 1 and 5 g/100 g) were analyzed during 2 weeks of storage at room temperature. Specific volume and width/height ratio of fresh breads were not affected by polyol addition, while it significantly decreased the moisture content of the bread. Propylene glycol significantly decreased water activity to 0.871 (1 g/100 g propylene glycol) and 0.867 (5 g/100 g propylene glycol) in comparison with the control (0.883). Evaluation of crumb hardness and moisture indicated that sorbitol and propylene glycol were able to diminish bread staling. The rise in hardness in polyol‐supplemented bread samples was not significantly more than the control between the first and second days of storage. Increase in hardness of bread samples was observed lower than the control after the second day in both levels of the sorbitol and 5 g/100 g propylene glycol. Acceptability of the breads, as indicated by panelists, was found to be higher than control bread for 5 g/100 g propylene glycol with 3.8 and 4.8 values, respectively. Results showed that propylene glycol can present the greatest effect on quality and shelf life of Barbari flat bread fortified with soy flour. PRACTICAL APPLICATIONS Flat bread plays a significant role in the diet of large portion of the Middle East population, but it is a highly delicate product. The three most common forms of bread deterioration are staling, moisture loss and microbial spoilage. One of the most frequent ways to prevent or control these problems is the use of additives such as polyols. Polyols may be a good choice to diminish the hardening phenomena, moisture loss and water activity, and increase the shelf life and sensory acceptability of bakery products. On the other hand, incorporation of soybean flour into food products, especially in developing countries, can provide good nutritional quality besides prolonging the shelf life of bread. The changes due to polyol addition need to be characterized if a viable commercial product should be achieved.

Saffron petal, as a byproduct of saffron processing, contains a considerable amount of antioxidant compounds. In the present study, the effect of drying methods (spray and freeze) and different wall structures (maltodextrin and pectin) was investigated on the physicochemical characteristics of microcapsules of saffron petal extracts. Results showed that the increase of the pectin ratio in wall composition leads to the increase of polyphenols content and antioxidant activity of microcapsules. Microencapsulation efficiency and loading capacity in pectin‐contained samples were higher than pure maltodextrin samples. Moreover, microcapsules obtained from spray drying method had higher microencapsulation efficiency and loading capacity in comparison with microcapsules obtained from freeze drying method. Also, scanning electron microscopy, X‐ray diffraction, and differential scanning calorimetry have been shown to be useful tools for establishing the difference between produced microcapsules. High‐performance liquid chromatography was used to evaluate the polyphenolic compounds of the microsphere. The chromatograms obtained from both encapsulation methods indicated high levels of routine in microcapsules of saffron petal extract. In addition, the release of polyphenols from microcapsules of saffron petal extract was evaluated under simulated gastrointestinal conditions. The results indicated that the release behavior of the microcapsules varied according to the type of drying method and wall composition. To assess the shelf life, the microcapsules were kept at different temperatures and relative humidities for 16 weeks. The microcapsules produced by freeze drying and containing high levels of pectin in wall composition had the highest antioxidant activity when kept in relative humidity of 11% and temperature of 4 °C. Practical Application Saffron petal is the huge amount of saffron by‐product and contains a number of various antioxidant compounds. Microencapsulation of its valuable compounds results in preventing the destruction of these compounds by environmental factors and their increased bioavailability. Indeed, this paper focuses on the release of microencapsulated powder in the simulated system of the digestive system that helps us to improve the shelf life of the final product during the process and controlled release of compounds in the food and pharmaceutical industries.

The fructans, inulin and oligofructose, were known to possess many physiologic properties. In the present study, the Box-Behnken design was used to determine the optimum extraction conditions of fructan from Eremurus spectabilis root powder (Serish) with water extraction, direct and indirect ultrasound assisted extraction methods that gave the maximum yield. Sonication amplitude (20-100 %), sonication temperature (30-70°C) and sonication time (5-40 min) were considered variables of direct and indirect ultrasound extractions while for conventional extraction the following variables were water to solid ratio (30-50 v/w), temperature (40-90°C) and time (5-40 min). A second-order polynomial model was fitted to each response and the regression coefficients were determined using least square method. There was a good agreement between the experimental data and their predicted counterparts. In addition to establishing the difference of these extraction methods, the scanning electron microscopy, Fourier-transform infrared spectroscopy, zeta potential and particle size analysis have been shown to be useful tools to investigate, approximate and predict characteristics of extracted fructan. Moreover, comparison of conventional extraction, direct sonication extraction, indirect sonication extraction showed the indirect sonication extraction is a suitable method for fructan extraction.

No abstract