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In this study, the effect of different amounts of konjac gum (KG) (0 to 0.2%) and sage seed gum (SSG) (0 to 0.2%) as experimental variables of the mixture design and fat content (0 to 3%) and homogenization rate (0 to 24000 rpm) as experimental variables of the process design on the viscoelastic characteristics of low-fat stirred yogurt were investigated. Based on the results of stress sweep test for different samples, the storage modulus (G') had a value more than the loss modulus (G''), explaining a solid-like behavior of the samples. Also, according to the stress sweep test, G' LVE (G' at linear viscoelastic region), G'' LVE (G'' at linear viscoelastic region), γc (critical strain), τy (yield stress), τf (yield stress at flowing point), and Gf (elastic modulus at flowing point) of the samples were significantly increased, especially for samples containing higher sage seed gum, with increasing fat content and homogenization rate. To optimize the properties in this study, G" LVE were considered to be minimum and G' LVE, γc, τy and τf were considered to be maximum. According to the mentioned properties, the optimized amount of KG was 0.19%, the amount of SSG was 0.01%, the fat content was 0.59% and the homogenization rate was 12075 rpm.

In this study, a double emulsion system was developed based on an optimized initial simple emulsion with the view to increase the stability of effective saffron compounds (crocin, picrocrocin and safranal). To this end the effect of various concentrations of surfactant (10, 12.5 and 15%) and different types of carbohysrates (sucrose, sorbitol, and dextran) on the stability of simple emulsion was investigated. The principal component analysis method was used to identify the relationships between the quantitative changes of the active components and quality attributes of the emulsion. Based on the results, day 7 was recognized as a critical point on which dramatic changes in the quality attributes of the emulsion coincided with the loss of saffron active compounds. In other words, physical changes in the stability of emulshion correlated well with the destruction trend of active compounds, although picrocrocin changes were found to be of independents. Also, it was revealed that the incorporation of 1% w/w sorbitol into the aqueous extract of saffron significantly decreased the loss rate of saffron active compounds in the emulsion. In addition, the double emulsion increased the half-life of saffron active compounds during a 14 day storage period. The results showed that double emulsion system was a suitable method for saffron extract, but the qualitative properties of initial emulsion also had a great influence on their stability. Multivariate analysis methods can also be used to clarify the relationships between the qualitative properties of the emulsion and the active compounds entrapped within it.

Introduction Escherichia coli is an important bacterial pathogen transmitted through contaminated water and food. The aim of this study was to evaluate the physical characteristics of nanoliposome essential oil (EO) and its antibacterial effect on E. coli. Materials and Methods Nanoliposomes were prepared by thin-film hydration and sonication. Particle size, polydispersity index, and encapsulation efficiency were assessed. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of free EO and nanoliposome barije EO were determined by broth macrodilution against E. coli. Also, effect of different concentrations of the MIC of EO was evaluated before and after encapsulation against the growth of bacteria over 24 h. Results The average particle sizes of the empty and EO loaded nanoliposome were 138.76 and 81.47 nm, respectively. Also, EO loaded nanoliposome had lower polydispersity. Moreover, the encapsulation efficiency of nanoliposomes was determined about 73.26%. MIC and MBC levels for EO loaded nanoliposomes decreased in comparison with free EO. Using 75% MIC of free EO in comparison with control, the bacterial count decreased by 3.528 and 1.12 log (CFU/mL) after 12 and 24 h, respectively. This reduction in the EO loaded nanoliposomes was 3.40 and 2.33 (CFU/mL) log (p

In this study the ability of Saccharomyces cerevisiae PTCC 5052 to adsorption of aflatoxin M1 was assessed. In order to improve operational efficiency, Alumina ceramic was analyzed as a potential support for immobilization of yeast cells. In immobilization process, results indicated that the binding abilities of AFM1 by live cells of Saccharomyces cerevisiae were higher than non-live immobilized cells on alumina ceramic within 48 hours (P1 solution (0.2 ppb) was passed through a ceramic substrate containing immobilized saccharomyces cerevisiae (both of live and non-live immobilized cells) in 5, 10 and 20 minutes. The results showed that the residual aflatoxin M1 in the solution after 20 minutes of circulation was minimal and the highest percentage of AFM1 reduction was 75. Alumina beads containing live immobilized yeast cells compared non- live yeasts, significantly reduced aflatoxin M1. The results of this study showed that the alumina ceramic can be used as a suitable bed for immobilization of saccharomyces cerevisiae to remove aflatoxin M1.

Saffron which has traditionally been used in different industries as well as in folk medicine, is considered one of the valuable resources of antioxidant. However, there is little information about extraction of antioxidant compound from different parts of this plant especially its petal. Solvent-assisted extraction is considered one of the most important methods for extraction of the most valuable compounds from plant sources and is applicable in both laboratory and industrial scales. In this study, box-behnken design was used in order to investigate the effect of time (60-200 min), temperature (25-85 ºC) and ethanol percentage (20–60%) on the yield of polyphenol, flavonoid and anthocyanin, and also the antioxidant activity and optimization of extraction process. Results showed that maximum yield of antioxidant compounds is achieved with extraction time of 104.29 min, extraction temperature of 66.31º C and ethanol percentage of 58.96%. Under these conditions, the values were 1134 (mg gallic acid/100 g) for polyphenol, 85.44(mg quercetin/100 g) for flavonoid, 3584.13(mg/100 g) for anthocyanin, 60.60% for DPPH free radical scavenging activity and 3.24 (mM) for ferric ion reducing antioxidant power.

Doughnut is a special fermented and fried snack. There are a few studies about wheat flour fortification with soy protein isolate to produce doughnut. The present research was done to study the effect on quality features of doughnut during preservation. Partial substitution of wheat flour with soy protein isolate at the levels of 0, 1, 2 and 5 g/100 g was carried out to determine its influence on quality characteristics of doughnuts. The water absorption and protein content of the samples were measured by Farinograph and kjeldahl method respectively. Quality characteristics of doughnut such as porosity and color were determined with Image J software. Sensory evaluation of doughnuts was carried out on 9-point hedonic scale by a panel of 12 judges.The protein content and water absorption of the fortified samples were higher, but their Volume, porosity and lightness were lower than the control. Control sample had the highest overall acceptability rating although the difference between samples were not significant (P>0.05). So it is possible to produce a doughnut fortified with 1-5% soy protein isolate with higher protein content without having significant negative effect on its acceptability.

Whey proteins are of wide application in the formation and stabilization of food emulsions. However, due to their high sensitivity to environmental conditions they quickly lose their functional properties. Glycolation of whey protein fractions is one of the methods used to modify their structure and improve their functional characteristics. The present work was carried out with the aim to prepare whey protein- starch conjugates and investigate the effect of protein to polysaccharide ratio on the quality attributes of oil-in-water emulsion. The results indicated that surface electrical charge decreased by increasing starch to protein ratio. On the other hand, changes in the surface and interfacial tension did not follow a clear trend in response to altering the mass ratio of protein. The drop size distribution curves were monomodal and nearly normal for all samples and became noticeably sharp with minimum width at protein to starch ratio 1:1. The finest and largest droplets were observed in the aforementioned sample and the one stabilized by modified starch, respectively. Studying the flow behavior of emulsions also revealed that starch containing sample exhibited the characteristics of near-Newtonian fluid, whilst the others were shown to have shear thinning pseudoplastic properties which became more distinct by increasing protein ratio leading to highest consistency index and lowest flow behavior index at %100 whey protein.

The purpose of this study was to investigate the effect of Lallemantia royleana seed gum on the properties of oil-in-water emulsions stabilized by whey protein using “Response Surface Methodology (RSM)”. For this purpose, emulsions with different whey protein concentrates (0.5_ 3%), seed gum (0 - 0.3%), and oil volume fraction (20- 50%) were prepared. Several properties of emulsions including mean diameter of droplets, zeta potential, surface tension and interfacial properties were studied. Selecting an appropriate model, the response-surface graph was drawn. For each response, a second-order polynomial model was developed using “Multiple Linear Regression Analysis”. Results indicated that increasing the gum concentration from 0 to 0.15% the mean diameter of the droplets will be diminished but its further increase would enlarge the size of particles. Zeta potential analysis showed that the more concentration of resin emulsions the more negative zeta potential of emulsion will be. The optimum formulation was suggested to be: 0.12% Lallemantia royleana seed gum, 4.69% whey protein and 21.59% oil.