Time filter

Source Type

Nezhad M.H.,Khorasan Research Institute for Food Science and Technology | Knight M.,Australian Department of Primary Industries and Fisheries | Britz M.L.,University of Tasmania
Food Science and Biotechnology | Year: 2012

In this research, changes were observed in cell surface proteins of a typical strain of the Lactobacillus casei was investigated in response to acidic growth conditions. Two dimensional electrophoresis and Western blot analyses were carried out to detect changes in relative abundance of proteins at the cell surface. The identity of the differentially expressed proteins extracted by LiCl, a chemical routinely used to extract surface proteins of lactic acid bacteria, was determined by MALDI-TOF/TOF MS. Many enzymes involved in glycolysis were up-regulated in the cell surface fraction following growth at low pH, including enolase, lactate dehydrogenase, and glyceraldehyde-3-phosphate dehydrogenase. Several of these proteins were also related to adhesion and generalized stress responses. It is demonstrated that growth of L. casei under acidic conditions caused molecular changes at the cell surface to develop an adaptive strategy corresponding to slower growth at low pH. © 2012 The Korean Society of Food Science and Technology and Springer Netherlands.

Hossein Nezhad M.,Khorasan Research Institute for Food Science and Technology | Stenzel D.J.,Queensland University of Technology | Britz M.L.,University of Tasmania
Iranian Journal of Microbiology | Year: 2010

Background and Objectives: Although members of the Lactobacillus casei group are known to survive under acidic conditions, the underlying mechanisms of growth at acidic condition and the impact of low pH on the relative level of protein expression at the cell surface remain poorly studied. Material and Methods: After confirming the taxonomy of L. casei strain GCRL 12 which was originally isolated from cheese and confirmed by 16S rRNA sequence analysis, the impact of acidic pH on growth rate was determined. Results: Late log-phase cells cultured at pH 4.0 showed obvious changes in Gram staining properties while transmission electron microscopy analysis revealed evidence of structural distortions of the cell surface relative to the controls cultured at pH 6.5. When comparing cytosolic or whole cell preparations on SDS-PAGE, few changes in protein profiles were observed under the two growth conditions. However, analysis of surface protein extracted by 5M LiCl demonstrated changes in the proportions of proteins present in the molecular weight range of 10 to 80 kDa, with some proteins more dominant at pH 6.5 and other at pH 4. Conclusion: These data suggest that surface proteins of this strain are associated with growth and survival at low pH. The function of these proteins is subject to further investigation.

Koocheki A.,Ferdowsi University of Mashhad | Kadkhodaee R.,Khorasan Research Institute for Food Science and Technology
Food Hydrocolloids | Year: 2011

Response surface methodology was used to investigate the influence of Alyssum homolocarpum seed gum (0.25-1%), Tween 80 (0.1-1%) and NaCl (0-1%) on characteristics of ultrasonically prepared corn oil-in-water emulsion. For each response, a second-order polynomial model was developed using multiple linear regression analysis. It was shown that increasing the gum concentration and Tween 80 content decreased the mean diameter of droplets, span and creaming index. Although the increase of gum concentration had a positive effect on viscosity, Tween 80 revealed to have no significant effect on these responses. Optimum formulation for a stable emulsion was found to be 1% A. homolocarpum seed gum, 0.96% Tween 80 and no NaCl. However, using salt at higher gum concentration did not have negative effect on the emulsion properties. © 2010 Elsevier Ltd.

Najafi M.N.,Ferdowsi University of Mashhad | Kadkhodaee R.,Khorasan Research Institute for Food Science and Technology | Mortazavi S.A.,Ferdowsi University of Mashhad
Food Biophysics | Year: 2011

The retention and shelf stability of cardamom oil entrapped in freeze- and spray-dried microcapsules coated with skim milk powder and modified starch was investigated. It was found that the retention of flavor in freeze-dried matrices was low and independent from the composition of wall material, whereas for the spray-dried microcapsules, it was much higher and markedly dependent on the type and percentage of coating material. It was also shown that the particle size of spray-dried powder greatly contributed to the flavor retention and surface oil content of microcapsules. Additionally, microscopic observation of powder particles revealed that the type of wall material and drying method distinctly influenced the morphological characteristics of powders which presumably caused a difference in their capability of cardamom oil retention. © 2010 Springer Science+Business Media, LLC.

Asadzadeh Shahir A.,Tarbiat Modares University | Javadian S.,Tarbiat Modares University | Razavizadeh B.B.M.,Khorasan Research Institute for Food Science and Technology | Gharibi H.,Tarbiat Modares University
Journal of Physical Chemistry B | Year: 2011

Interaction of a food dye, tartrazine, with some cationic conventional and gemini surfactants, tetradecyltrimethylammonium bromide (TTAB), N,N′-ditetradecyl-N,N,N′,N′-tetramethyl-N,N′-butanediyl- diammonium dibromide (14,4,14), and N,N′-didodecyl-N,N,N′,N′- tetramethyl-N,N′-butanediyl-diammonium dibromide (12,4,12), were first investigated comprehensively employing conductometry, tensiometry, and UV-visible spectroscopy. Tartrazine was found to behave in the same manner as aromatic counterions. The formation of ion pairs reflected as a considerable increase of the surfactant efficiency in tensiometry plots and their stoichiometry were determined by Job's method of continuous variations. For the tartrazine/TTAB system, nonionic DS3, ionic DS2-, and/or DS2 - ion pairs, their small premicelles, and tartrazine-rich micelles were constituted as well as dye-containing TTAB-rich micelles. Insoluble J-aggregates of DS- ion pairs and cylindrical surfactant-rich micelles were also formed in tartrazine/gemini surfactant systems and recognized by transmission electron microscopy. The zeta potential and the size of the aggregates were determined using dynamic light scattering and confirmed the suggested models for the processes happening in each system. Cyclic voltammetry was applied successfully to track all of these species using tartrazine's own reduction peak current for the first time. © 2011 American Chemical Society.

Soleimanpour M.,Ferdowsi University of Mashhad | Koocheki A.,Ferdowsi University of Mashhad | Kadkhodaee R.,Khorasan Research Institute for Food Science and Technology
Food Research International | Year: 2013

The effect of composition (whey protein concentrate, Lepidium perfoliatum seed gum, and oil content) of corn oil-in-water emulsions on their physical properties, droplet size and viscosity was studied using response surface methodology (RSM). For each response, a second-order polynomial model was developed using multiple linear regression analysis. The results indicated that the response surface models were significantly fitted for all response variables studied. It was shown that all emulsion components greatly influenced the physical properties of emulsion and its overall stability during storage. The main effect of L. perfoliatum seed gum was observed to be significant in most of response surface models. Therefore, the concentration of this gum should be considered as a critical variable for the formulation of emulsions. The overall optimum region resulted in a desirable emulsion was predicted to be obtained by combined level of 0.59% L. perfoliatum seed gum, 6% WPC and 21.95% oil volume fraction. © 2012 Elsevier Ltd.

Soleimanpour M.,Ferdowsi University of Mashhad | Koocheki A.,Ferdowsi University of Mashhad | Kadkhodaee R.,Khorasan Research Institute for Food Science and Technology
Food Hydrocolloids | Year: 2013

In this study the effect of Lepidium perfoliatum seed gum on the properties of whey protein concentrate (WPC) stabilized corn oil-in-water emulsions at pH 7 was investigated. Various concentrations (0-0.6% w/v) of L. perfoliatum seed gum were used together with 2% (w/v) WPC to emulsify corn oil in water at a ratio of 1:5. Quality attributed such as particle size distribution, creaming profile and coalescence rate during storage at 4 and 25 °C; surface and interfacial tension; zeta potential and viscosity of the emulsions were determined. The results indicated that the addition of L. perfoliatum seed gum had no significant effect on zeta potential but the surface and interfacial tension increased with the rise of gum concentration. It was also found that the addition of L. perfoliatum seed gum to WPC emulsions at a critical concentration of 0.2% (w/v) caused flocculation of oil droplets, which resulted in marked increase in particle size and the creaming rate. However at higher gum concentrations beyond this value, the particle size remained constant, apparently because of the high viscosity of the aqueous phase. At all concentrations tested, emulsions stored at 4 °C were more stable except for those containing 0.2% L. perfoliatum seed gum. © 2012 Elsevier Ltd.

Mollafilabia A.,Khorasan Research Institute for Food Science and Technology
Acta Horticulturae | Year: 2010

Saffron (Crocus sativus L.) is used in food industries, cosmetics, medicine, dyeing, perfume making and art and is one of the most valuable products in agriculture. Iran is the largest producer (60%) and exporter (90%) of the world. There have not occurred any considerable modifications in saffron cultivation since medieval centuries in Spain. Yield average of Iranian saffron is 4.7 kg/ha. This research presents the findings of the application of a new method of cultivation for four years aiming at shortening farm ages, optimum utilization of production resources and finally yield increase/ha. Extension of its results to the respective locations of saffron cultivation and increasing income of national economics compared with traditional (conventional) method is the ultimate purpose of such a study. The research was arranged in the form of a randomized complete block design (RCBD) with four replicates. In the new method there were three factors (time of planting: early in June, planting corms of 8 g and higher and one summer irrigation in early August). In the traditional method planting was in September, without sorting corm weight and without summer irrigation. The rest of cultivation practices were the same for both methods. Annually, flower weight, stigma and style (bunched saffron), and stigma/m 2 were recorded in each replicate during the flowering period and the data were statistically analyzed and mean comparisons were grouped. In the first year, all observations were significant at ≤0.01. In the fourth year, flower weight and subsequently, yield of stigma + style, and stigma were significant at P≤0.05 and plant height, biomass (yield of dry leaves) and weight of produced corms were significant at P≤0.01. In the final year (fourth year) characters under study were combined and analyzed. Results were significant at P≤0.01. So with 99% confidence, it can be suggested that the new method can be recommended. Four year means of characters under study were calculated by Duncan's test; all characters are placed in group (a) and for the traditional method in group (b). Yield average of stigma + style, and stigma were 11.61 and 8.64 (48% superiority and about two fold) in the new method and 6.01 and 4.47 kg/ha in the traditional method, respectively. Yield average of biomass (forage of dry leaves) was 1.55 in the new method and 1.1 t/ha in the traditional method (29.4% superiority) and also average of corm weight was 14.1 in the new method and 7.57 t/ha (44.1% superiority) in the traditional method. These results correspond with those obtained by Iranian and foreign researchers. Cost-effective saffron production is related to the number and flower weight in different ages of farms. In the new method, economical yield of saffron is harvested in 4 years and farm age can be decreased by half.

Vahid B.R.,Ferdowsi University of Mashhad | Saghatoleslami N.,Ferdowsi University of Mashhad | Nayebzadeh H.,Ferdowsi University of Mashhad | Maskooki A.,Khorasan Research Institute for Food Science and Technology
Chemical and Biochemical Engineering Quarterly | Year: 2012

Solvent-free technique was employed in this work in order to assess the influence of the calcination temperature on the activity of Al-promoted sulfated zirconia. The catalyst was analyzed by XRD and IR-spectrum method, and catalytic activity was examined by esterification reaction of oleic acid. XRD analysis revealed that a decline in the percentage of tetragonal phases of zirconia was observed by increasing the calcination temperature from 500 to 900 °C. In addition, a reduction of sulfate groups as SO 4 2- on zirconia surface was observed. As a consequence, a decline in Brønsted sites with calcination temperature enhancement also prevailed. Therefore, the size of Al-promoted sulfated zirconia particles was increased accordingly. On the other hand, with the aluminum sulfate loading, the amount of sulfate ions on Al-promoted sulfated zirconia surface was enhanced and a reduction in particle size of Al 2O 3/S-ZrO 2 was also observed, as compared to non-promoted. The result of this study revealed that an increase of sulfate and alumina groups causes a raise in the acidity of catalyst. Furthermore, the calcined Al-promoted and non-promoted sulfated zirconia would convert 96.10 % and 89.36 % of oleic acid to biodiesel, respectively. Therefore, Al 2O 3/S-ZrO 2 as a catalyst exhibits a higher activity than S-ZrO 2.

Mirzaee H.,Khorasan Research Institute for Food Science and Technology | Pourzaki A.,Khorasan Research Institute for Food Science and Technology
International Review on Computers and Software | Year: 2011

Product miniaturization with progressively decreases costs, because of increasing consumer demands in Computers, Telecommunications, Instrumentation & Test Equipment, Military & Aerospace, and Consumer & Automotive. In this paper, characteristics of passive components such as resistors, capacitors, and inductors, as the non-active elements, in the microelectronic packaging industry have been described. In this work, trends of articles and patents in passive components have been achieved. New electronics designs are requiring that greater functionality fit into smaller, more portable products, and the number of passive devices required for these products has increased significantly. Fabrication and commercialization of embedded passives have been also discussed. Finally, current and future of integrated passive devices such as RFID tags are discussed and forecast marketing of them has been prospected. © 2011 Praise Worthy Prize S.r.l.-All rights reserved.

Loading Khorasan Research Institute for Food Science and Technology collaborators
Loading Khorasan Research Institute for Food Science and Technology collaborators