m. h. haddad khodaparast

Hydrocolloids, playing different roles including thickening, stabilizing, gelling and improving texture of foods are among additives widely used for improvement of quality in food industry. Recently, demand for hydrocolloids with special functional properties has grown, therefore, finding new sources of gums with proper attributes is of enormous importance. Therefore, this study aimed at investigating the effect of variables including temperature (30-80°C), concentration (5-9%) and shear rate (0.1-1000 s-1) on apparent viscosity and flow behavior of malva flower mucilage solution. The results showed that malva flower mucilage was rheologically pseudoplastic with this behavior being enhanced at higher concentrations (<n). The effect of temperature and concentration on flow index and consistency coefficient was also significant (p≤0.05). At low concentrations, power law model and at high concentrations, casson and bingham models best fitted with mucilage solution. Also mucilage solution at 5% and 9% concentrations showed the lowest and the highest temperature dependency, respectively.

Marshmallow (Althaea officinalis) belonging to Malvaceae family possesses mucilage containing cells in stem, petiole, petals and seeds showing antimicrobial activity, anti-inflammatory, immunomodulatory effects among others. In this study, in order to determine the characteristics of marshmallow seed mucilage, as a potential new source of hydrocolloid, some instrument methods (Scanning Electron Microscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, etc.) were used and viscosity of mucilage was determined. SEM analysis showed that the mucilage had an amorphous structure and disordered particle size. Mucilage solution at pH of 7 had negative charge; zeta potential of -22.4 mV, electrical conductivity of -1.753 mS /cm and particle size being 255.1 d.nm. Its glass transition temperature (Tg) was 37.9 °C and the melting process started at 34.3 °C to 182.2 °C. An endothermal peak was observed at 92.6°C. Heat of infusion was 199.19 J/g. The most important functional groups identified by FTIR were an asymmetric stretching of double-bond (C=0) in the deprotonated carboxylated groups at 14.3 and 1627 cm-1 vibratory stretching ring of pyranose at 1280 cm-1 and 1115 cm-1 as well as glycoside bonds at 617 and 780 cm-1. Marshmallow seed mucilage solution showed a shear–thinning (pseudoplastic) behavior and the most predominant elements found in the mucilage were carbon (26.59%), potassium (26.39%).

Gundelia Tournefortii L. seed oil could be potent enough to consider as edible oil possessing antioxidant properties. To investigate that, the antioxidant activity of this oil and its effects as a natural antioxidant agent was studied. The oil was extracted by maceration method using ethyl ether as a solvent. Then, DPPH method was applied to investigate the radical scavenging activity of the oil and its fractions. Peroxide (PV) and TBA values of the soybean oil (including either 5% or 10% of G. Tournefortii L. seed oil) were determined through an oven test. Moreover, HPLC-UV was employed to qualify and quantify the phenolic compounds. The results indicated that radical scavenging activity of unfractionated oil (TF) was 123.26±0.42 µM; and the methanolic fraction (MF) (85.82±0.58 µM) had a lower scavenging activity than the ethanolic one (EF) (55.09±0.18 µM). However, it was vice versa for non-soluble methanolic (MLF) and ethanolic fractions (ELF) (106.28±0.64 µM and 145.76±0.09 µM, respectively). Luteolin 7-aglycone (0.1878 mg/g oil) and Chlorogenic acid (0.1113 mg/g oil) were determined by HPLC-UV as the most major phenolic compounds of this oil. Total amount of the phenolic compounds was 0.7935 mg/g oil. Finally, a 13day oven test revealed that the highest antioxidant activity was measured during the 8th and 9th day of the test, considering PV and TBA, respectively. This study states that Luteolin 7-aglycone and Chlorogenic acid are among the most abundant phenolic compounds in G. Tournefortii L. seed oil and these compounds are mainly ethanol soluble.

In the present study, the oxidative stability of nine Iranian commercial olive oils, including four virgin samples and five deodorized ones, was compared to that of two foreign virgin olive oils. In total, the foreign samples had the MUFA/PUFA ratios (av. 9.27) higher than those of domestic ones (av. 5.70). The peroxide and acid values of the olive oils studied ranged from 8.5 to 14.5 meq/kg and from 0.1 to 4.27 mg/g, respectively. Tocopherols content of the foreign olive oils (av. 436.7 ppm) was averagely higher than that of the domestic olive oils and even about two times that of domestic virgin ones (223.4 ppm). On average, the foreign virgin olive oils contained phenolic compounds (154.0 ppm) higher than that of the domestic ones (112.3 ppm) and especially deodorized olive oils (46.0 ppm). The oxidative stability of oil samples was suitably interpreted in terms of chemical composition data, so that the foreign virgin olive oils had more appropriate chemical composition in total, and therefore, indicated oxidative stabilities higher than those of the domestic virgin and deodorized olive oils.

Battered foods are popular due to appearance and taste characteristics such as their crispy texture, desirable color and flavor. The quality of coated products is influenced by rheological properties of the batter. In this study, the rheological properties of two types of batters (batter with typical formulation and batter with 2% Methyl Cellulose) were investigated. The batters were formulated using different ratios of wheat, soy and corn flours. The batters in power-law model showed shear-thinning behavior. The rheological properties varied with different types of flours and their combination ratios. MC increases the batter consistency and enhanced the shear-thinning behavior of the batters. The values of flow behavior index (n) in different batter formulations were found between 0.36 to 0.62. Batters viscosity varied from 0.68 to 7.33 Pa.s at 200 s -1 shear rates. In all samples, batter with 50% soy flour provided the highest apparent viscosity among all formulations.

Types and contents of the chemical compounds found in olive oil, including fatty acids, antioxidants and pigments, indicates the oil quality, which in turn depends on several factors, including cultivar, climate, extraction method, and maturity of he olive fruit. Research has shown that tocopherol and polyphenol contents depend on cultivar and the cultivation region, respectively, while fatty acid content depends on both of these factors. Iranian olive oils have a different chemical composition and, consequently, different oxidative stability. Therefore, the aim of the present study was to investigate the chemical composition and physicochemical chartacteristics of commercial types of Iranian virgin and refined olive oils.

Iranian olive oils, including four virgin (C, D, F and H) and five deodorized (A, B, E, G and I) samples, as well as two foreign virgin samples (1 and 2) were purchased from local stores. To determine fatty acid compoition and compositional, chemical and physical indicators, national and international laboratory methods were used. All determinations were performed in triplicates.

The results showed that the main fatty acids in the Iranian commercial olive oils were monounsaturated fatty acids (MUFA), particularly oleic acid (C18:1); saturated fatty acids (SFA), particularly palmitic acid (C16:0); and polyunsaturated fatty acids (PUFA), particularly linoleic acid (C18:2). However, the compositional, physical and chemical characteristics, such as peroxide value, acid value, polar compounds, the unsaponifiable matters, phenolic compounds and tocopherols, which affect the oxidative stability of fats and oils, were significantly different among the different olive oils.

The available literature shows that no comprehensive research has been conducted on the physicochemical properties of commercial olive oils in Iran, despite the fact that the domestic production of olive oil, because of its special importance with regard to its more desirable fatty acid composition compared to other edible oils, as well as its unique microstructure, has had an increasing trend. Hence, investigation into the effects of climate and agricultural conditions on the properties of olives and a better knowledge of raw material characteristics will make it possible to produce edible oils with higher quality and greater stability.

Nowadays, consumption of whole flours and flours with high extraction rate is recommended, because of their large amount of fiber, vitamins and minerals. Despite nutritional benefits of whole flours, concentration of some undesirable components such as phytic acid is higher than white flour. In this study, the effect of several sourdough lactic acid bacteria on toast bread was investigated. Sourdough was made from lactic acid bacteria (Lb. plantarum, Lb. reuteri) with different dough yields (Dy) and incubated at 30˚C for 20 hours, then added to dough in the ratios of 10, 20 and 30% replacement. Breads supplemented with Lb. plantarum sourdough had lower phytic acid. Higher replacement of sourdough and higher DY caused higher decrease in phytic acid content. Sourdough made from Lb. plantarum, DY = 300 and 30% replacement caused the highest decrease in phytic acid content (49.63 mg/100g). As indicated by the panelists, Lb. reuteri sourdough can present the greatest effect on overall quality score of the breads. DY reduction caused a decrease in bread quality score. Sensory score of toast bread was 81.71 in the samples treated with Lb. reuteri sourdough with DY = 250 and 20% replacement.

In this research, antimicrobial activity of extract of Salvia leriifolia were investigated with different concentrations of the extract (5000, 10000, 15000 and 20000 mg/kg) on Staphylococcus aureus count and Total viable count in hamburger at different time intervals: after treatment (day 0) and after storage for 15, 30 and 45 day at -12˚C, all microbiological analyses performed at 3 replication. The results showed that both of microbial total count and the number of Staphylococcus aureus in all samples with different concentrations of extract, decreased during storage. This decreasing effect was significant on day 15 and 30 for Staphylococcus aureus and total count, respectively. Our data also showed that the extract of Salvia leriifolia at highest concentration (20000 mg/kg) caused maximum reduction compared to other concentrations and extract at lowest concentration (5000 mg/kg) was less effective in initial Staphylococcus aureus population and microbial total count. These data indicate that Salvia leriifolia extract can exhibit antimicrobial activity against Staphylococcus aureus; so it can be considered as an alternative natural preservative in food products.

The effect of two types edible coatings, based on methylcellulose (MC) and gum tragacanth (GT) in combination with soy flour on physiochemical properties of fried donuts were studied. Dough was prepared with 0, 5 and 10% substitution of wheat flour with soy flour. Dough surface coated with hydrocolloid solutions (1% w/w) then fried at 150°C. Addition of soy flour did not show significant effect on moisture and oil content of the fried donut (P>0.05) but significantly (P<0.001) reduced the volume of the fried donuts. However, coating was effective method to reduction of oil content. Because of film forming properties, GT and MC coatings significantly (P < 0.05) reduced oil uptake but they did not have significant effect (P > 0.05) on moisture content and volume of the fried donut. Farinograph evaluation of dough showed that the addition of 10% soy flour considerably (P< 0.001) increased water absorption.

In commercial, technological and scientific aspects, control of colorants compounds, produced from tow different source: sugarcane and processing is very important. As an example of colorants with plant source, anthocyanins, xanthophylls, flavonoids and beta-carotene can be mentioned. Some material like bentonite can act like as active carbon and dioxide sulfur in absorbing polyphenol oxidase, phenols, charged molecules and etc. The adsorption of phenols from extracted products reduces the rate of enzymatic reaction colorful materials are usually affecting the efficiency and quality of final products and should be removed from raw sugarcane juice. In this study, first of all, raw sugarcane juice treated by bentonite compared with the sample purified with lime and so optimum quantity of bentonite and pH were recognized. Experimental results indicated 1.5gr/l bentonite and pH=4.5 had the best results in reduction of syrup color. As a second step, in order to increasing the effectives of bentonite adding gelatin was checked and it is compared by pure bentonite for optimizing the time and temperature of process. The experimental results indicated that 0.02gr/l gelatin in 100C° for 60 min are optimum conditions for purification of raw sugarcane juice in processing with bentonite.