فهرست مطالب h. behmadi

The new gluten-free pasta formulations based on the ratio of corn: rice: quinoa flours (20:60:20) enriched with the different percentages (0.5, 1, 1.5, and 2%) of β-glucan and xanthan (XG) were produced to reduce the gluten-related diseases and glycemic responses. These were then compared with each other and the control (wheat flour) in terms of texture, chemical composition, rheology, color, cooking quality, sensory analysis, prebiotic activity, glucose release, rapidly and slowly digested starch (RDS and SDS), and resistant starch (RS). The highest and lowest values of loss and storage moduli were for the control and sample 1 (2% β-glucan and 0.5% XG), respectively. The control and sample 1 were also comparable in terms of textural and sensorial characteristics. The L* (brightness) of cooked and raw sample 3 reached maximum level, and the highest values of b* and a* were associated with the cooked and raw control. The superior cooking quality was related to the sample 3 (1.5% β-glucan and 1% XG) while sample with 0.5% β-glucan and 2% XG had the minimum value. Regarding functional properties, the sample 3 was the superior sample in terms of prebiotic activity, glucose release, RSD, and RS while the control showed the maximum glucose release in all digestion intervals.

Nowadays, there is a great interest in using yogurt sauce as a flavored dressing for salads and foods. The current study aimed to determine the possibility of producing probiotic yogurt sauce and evaluate its physicochemical, microbiological, sensory and rheological properties throughout refrigeration storage. Lactobacillus rhamnosus was encapsulated with sodium alginate and resistant starch using the emulsion method. The survival of free and microencapsulated L. rhamnosus was studied in simulated gastrointestinal conditions. Two forms (free and microencapsulated) of L. rhamnosus were added to the yogurt sauce. The samples were kept for 30 days at 4 ˚C and evaluated on interval days (1st, 10th, 20th, and 30th) for the above mentioned properties. Survival improvement was demonstrated in microencapsulated L. rhamnosus compared to free L. rhamnosus.  After two hours, the free form of L. rhamnosus showed five logarithmic cycles decreasing in cell viability, while microencapsulated L. rhamnosus presented only one logarithmic cycle reduction. Similarly, on day 30 of storage, the number of viable microencapsulated L. rhamnosus cells in the probiotic yogurt sauce was 6.61 log CFU/g, while the viable count for a sample containing free L. rhamnosus was 5.00 log CFU/g. The produced probiotic yogurt sauce was considered a pseudo-plastic fluid and presented mayonnaise behaviour. Moreover, samples containing microencapsulated probiotic bacteria displayed lower post-acidification values than samples containing free bacteria. The microencapsulation of probiotic bacteria improved the sensory quality of the produced probiotic yogurt sauce.  Hence, producing a probiotic yogurt sauce with desirable properties is possible.

In this study the rheological and textural properties of Iranian white cheese produced by ultrafiltration technique containing gum tragacanth and xanthan gum each in the range of 0-0.1%, and basil seed and linseed mucilages each in the range of 0-0.2% were evaluated. According to the results obtained, values of Elastic (G/) and viscous (G//) moduli increased with increasing frequency sweep in all the cheese samples. G/ was always greater than G//. The values of G/ and G// in the samples containing 0.05% of gum tragacanth, 0.05% of xanthan gum and 0.1% of basil seed mucilage and containing 0.05% of xanthan gum, 0.1% basil seed and 0.1% linseed mucilage were maximum and in samples containing 0.1% of xanthan gum and 0.2% of linseed mucilage and containing 0.1% of gum tragacanth were minimum. By increasing basil seeds mucilage in the samples, hardness, cohesiveness, gumminess and chewiness increased in comparison with the control sample (p<0.01). According to the results obtained, for preparation of white cheese produced by ultrafiltration technique, using 0.05 % of gum tragacanth, 0.05 % of xanthan gum and 0.1 % of linseed mucilage, is recommended.

The halophyte Salicornia was recently introduced as a fresh vegetable crop that thrives in extreme salty conditions. In this study, the ash, minerals, heavy metal and nitric and nitrite anions in different parts (root, aerial parts and seeds) of Salicornia europaea L. were evaluated. The results showed that the ash content and sodium in the aerial parts was the highest and in the roots the lowest (P<0.05). But, potassium, copper and calcium between different organs and seed were not significant. While zinc and magnesium in seed and iron in root were higher, and zinc, manganese and magnesium content were lower in the root than other parts (p<0.05). Salicornia roots had the lowest arsenic and cobalt and the highest lead (p<0.05). The seeds containeed the lowest lead, cadmium, mercury and nickel. The aerial parts of this plant also had the least chromium and the highest levels of cadmium, mercury, nickel and cobalt. The mercury in different parts of the Salicornia was lower than the standard value. The lead in the root and cadmium in the aerial parts and chromium, arsenic and nickel in all parts were higher than the limit allowed. The highest nitrate content and the lowest nitrite content in aerial parts and the lowest nitrate content and the highest nitrite content were observed in the seeds (p <0.05). In all studied parts, the nitrate content was found in standard limit. According to the results, aerial parts of Salicornia can be used as a source of calcium, iron, zinc and magnesium.

The purpose of this research was to stop the proliferation of insects and microorganisms in dried fruits of fig cv. Sabz EStahban and to preserve the quality of the fruits by decreasing O2 and increasing CO2 and N2 in modified atmosphere packaging. Mold and yeasts, total counts of bacteria, commercial color, Lab factors, acidity, moisture, mold mycelium, alive and dead larva, alive and dead insects were evaluated. The properties were evaluated after 3 and 6 months storage of samples at 25 and 40°C. Gas treatments were: a) 70% N2 + 25% CO2 + 5% O2; b) 75% N2 + 50% CO2 + 5% O2; c) 20% N2 + 75% CO2 + 5% O2; d) 80% vacuum; e) control sample: 78% N2 + 0.3% CO2 + 21% O2. The effects of gas treatments were insignificant on color, acidity, and moisture, while they were definitely significant on granary pests such as larva, molds and yeasts, and bacteria. Reducing oxygen killed larva, fungi and bacteria. Control sample had the lowest dead larva. Modified atmosphere packaging and vacuum treatment caused significant depletion in granary pests in dried figs. So it can be a good replacement for methyl bromide.

Salicornia is a valuable halophyte annual plant in the most species. This salinity tolerance plant that grows in salt water marshes are found all over the world. Since salinity is a major stress factor, Salicornia is a priceless edible vegetable, considered to be a favourable resource for cultivation in arid and semiarid coastal zones. However, the important thing is that its properties should be well known especially as a leafy vegetable. On the other hand, Salicornia bigelovii is a perishable vegetable, with short storage life under ambient conditions. Thus, knowing its characteristics can be a great help to preserve it longer. Accordingly, the physicochemical properties, chemical composition and respiration rate of Salicornia biglovii grown in Aq-Qalla Salinity Research Station, Golestan Agricultural and Natural Resources Research and Education Center, Iran were investigated in this paper. The results showed that the moisture content, total soluble solidscontent, pH, titratable acidity, ascorbic acid content, salinity content, respiration rate, maximum force, displacement, and color indices (L*, a*, b*) of S. bigelovii are 89.67%, 15.83%, 6.11, 0.05%, 0.03%, 56ds/m, 26.80 mgCO2/kg.hr, 1.4 N, 1.47 mm, and 23.69, -6.77, 15.73, respectively. With respect to S.bigelovii plant as a leafy green vegetable, this plant is considered as a high respiration vegetable group.

Interesterification as an efficient tool in fat manipulation and producing tailor-made fats is an important process in oil technology. In this project random chemical interesterification was used as a substitute for hydrogenation to produce zero-trans fats, suitable for margarine and shortening production.

A mixture of sunflower oil and fully hydrogenated soybean oil (soy flake) (70:30 w/w) was interesterified, with sodium methoxide (0.5 %) as catalyst, at 110 °C, 100 mm Hg. vacuum, and 30-min processing time. The physical and chemical characteristics of the mixture, including slip melting point, acid value, iodine value, peroxide value, remaining soap, and moisture content, were determined before and after interesterification. In addition, in order to study the trend of random equilibrium before and after interesterification, the following were determined: the cis- and trans- (elaidic acid) fatty acid composition by gas chromatography (GC), the solid fat content (SFC) by NMR, and the type of fatty acid in the 2- position of triglyceride by enzymatic (lipase) hydrolysis, followed by thin layer chromatography (TLC) and GC.

The results showed that the tailor-made fats produced by interesterification had a significantly lower slip melting point (34 °C) compared to that of the mixture before interesterification (56 °C), which is considered suitable for producing shortening and margarine. As expected, the difference between the iodine values of the oil mixture and the structured product was not statistically significant. As a result of rearrangement of the fatty acid residues, SFC decreased and the SFC curve indicated better plastic properties in the product. The fatty acid composition did not change, indicating that the process had not affected the chemical structure of fatty acids, and the amount of trans isomers derived from the flake was constant (0.36 %). The product had a high content of polyunsaturated fatty acids, with P/S+T=1/13, implying better nutritional quality of the interesterified product, as compared to hydrogenated oil.

According to the results obtained, chemical interesterification for manipulation and rearrangement of fatty acid residues in triglyceride molecules, with a view to producing margarine and shortening base stocks with suitable nutritional and functional properties, is possible at a pilot scale. Continuation of the work at the industrial scale is recommended.