mohammadali sahari

Advanced glycation end products (AGEs) are a group of compounds formed during the Maillard reaction, which can have adverse effects. This study aims to investigate the formation of fluorescent AGEs using the response surface method (RSM). Factors such as protein type ((whey protein 2.0, 3.5, and 5.0 %w/v) and casein (1.0, 2.0, and 3.0 %w/v)), three types sugar ((glucose and frouctose (0.2, 0.6, and 1.0 M) and lactose (0.1, 0.3, and 0.5 M)), and pomegranate peel (PPE) concentration (250.0, 500.0, and 750.0 ppm) along with their interactions are analyzed. The results of this study showed that, the type of protein, type of sugar, and concentration of phenolic extract from pomegranate peel were effective in preventing the formation of AGEs, and the pomegranate peel extract (specially at 750.0 ppm) was able to effectively prevent glycation reaction. According to the results, protein type and concentration significantly influence AGEs formation. The inhibitory activity of the extract in the model system containing casein was lower than the system containing whey protein, and overall, the inhibitory power decreased with an increase in protein concentration. By changing the type of sugar present in the model system, the inhibitory behavior of the pomegranate peel extract became complex, showing increased, decreased, or no effect in some cases. Further investigations can suggest the use of this extract, especially in the formulation of food products, including infant formulas.

Consumers prefer not to use synthetic preservatives so, natural ones such as essential oils (in this research, garlic oil (GO) are mostly consumed in food products as an antimicrobial agents. Application of garlic oil in food industries is limited. Because of its water insolubility, volatility, pungent odour and flavor, and low stability. Encapsulation could eliminate its restrictions. In the present study, different concentrations of free and encapsulated garlic oil in ß-cyclodextrin (GO/ß-CD) were used for formulation of sausage

Five types of sausage were produced, including control (without garlic oil), containing free garlic oil (GO), and three samples containing 546, 818, and 1364 mg of encapsulated garlic oil per kg. After that, changes of pH, color, oxidation indices (PV and TBARs(, monitoring of B. cereus, S. aureus, E. coli, and S. enterica, and sensory (taste, color, odor, and acceptability by 8-point hedonic test) properties were studied during 29 days storage at 4oC.

By increasing the GO/ß-CD content of samples, the overall color changes decreased. The pH of all produced sausages remained constant. At the end of storage, PV was not significantly changed, and TBARs changing was very low. S. aureus was the most susceptible, followed by S. enterica, E. coli, and B. cereus. In sensory evaluation, the panelists did not distinguish between the control and the samples containing GO/ß-CD. Encapsulation of garlic oil with beta-cyclodextrin did not affect the taste of the produced sausages. Due to good antimicrobial properties of garlic oil, it can be used in meat products as a natural preservative.

This research study was accomplished for the extension of meat-based hamburgers during frozen storage. Control hamburgers were produced at three ground meat concentrations (30, 70, and 90%). Also, potassium lactate (PL) and sodium diacetate (SD) were added to the hamburger by 3% and 0.15%, respectively, to investigate their effects on moisture content, oxidative stability, and microbial growth. The results showed that the addition of PL and SD relatively maintained the moisture especially when meat ground was 70%. On this basis, after 150 days of storage, moisture was 59.70% for the hamburger with 70% compared with 58.56 obtained for the control. Higher oxidative stability was obtained for the hamburger with PL and SD and meat ground of 30% so that peroxide values were 2.49 and 1.97 meq O2/kg, and 1.82 mg and 1.52 MDA/kg respectively for control and sample after 150 days of storage. The addition of PL and SD inhibited the growth of salmonella, limited the E.coli, molds, and yeasts growth.

Fresh garlic includes several preservative and medicinal characteristics; however, its major bioactive components react and convert to other chemical compoundsas soon as its tissues are injured. Garlic oil is extracted from garlic and its use in food industries is limited due to its strong odor, taste, volatility and low solubility in aqueous solvents. The aim of the present study was to investigate physicochemical, microbial and sensory properties of low-fat salad dressings containing encapsulated garlic oil in ß-cyclodextrin (GO/ß-CD).

Five types of salad dressing, including control with no garlic oil, a sample with free garlic oil and three samples containing 546, 818 and 1364 mg GO/ß-CD kg-1salad dressing were prepared. Then, pH, color and antioxidant [(peroxide value and thiobarbituric acid reactive substances], antimicrobial (monitoring of four pathogens of Bacillus cereus, Staphylococcus aureus, Escherichia coliand Salmonella enterica) and sensory (taste, color, odor and acceptabilityby 8-point hedonic test) properties of the samples were assessed during 41 days of storage at 4 oC.

The minimum and the maximum color differences belonged to GO/ß-CD-3 sample containing 1364 mg GO/ß-CD kg-1salad dressing and sample containing free GO, respectively. Yellowness of samples containing encapsulated GO decreased and direct relationships were seen between decreasing of the sample yellowness and quantity of GO/ß-CD sample. During the storage, pH and peroxide value PV slightly increased. Staphylococcusaureuswas the most sensitive strain to free and encapsulated garlic oil.Escherichiacoli, Salmonella entericaand Bacillus cereus showed lower sensitivities to the oil. Sensory results showed no significant differences between the tastes of control and free or encapsulated garlic oil and GO/ß-CD-2 samples containing 818 mg kg-1encapsulated garlic oil, equal to 90 mg kg-1free garlic oil. However, these two treatments included significant differences with samples containing free garlic oil. Results revealed that encapsulation of garlic oil with ß-CD included no adverse effects on taste of the salad dressings. Therefore, GO/ß-CD-2 (818 mg GO/ß-CD kg-1salad dressing) can be suggested as a natural antimicrobial agent for the functional mayonnaise production.

A novel approach for bio-lubricant production from rapeseed oil-based biodiesel using ultrasound irradiation: Multi-objective optimization Moringa oil is used as a useful oil in the food, medicinal, cosmetic and health industries. Also past research has shown that microwaves can increase the extraction efficiency of oil by disintegrating the cellular structure of oil seed. Therefore, in this research, for increasing oil extraction efficiency, microwave pretreatment was used before oil extraction from Moringa seeds by spiral press. In this study, the optimization of oil mechanical extraction from Moringa seeds was done using the Response Surface Methodology. In this study, extraction experiments were done with microwave pretreatment at different level of times (2, 3 and 4 min) and powers (200, 400 and 600 W). The results showed that the extraction efficiency increases and then decreases by increasing microwave time and microwave power. The optimum extraction efficiency was 56.55% during the microwave action time of 3.02 min and the microwave power intensity of 380.92 W. Due to the high values of correlation coefficients (R2 = 0.97) the predicted model for oil extraction efficiency can be evaluated properly.

This study evaluated the ability of fennel extract to improve the quality of refrigerated minced silver carp over a period of 16 days. Minced silver carp were treated with fennel extract (0.5, 1 and 1.5% w/w), and beta-hydroxy toluene (BHT 200 ppm). The control and the treated fish samples were analyzed periodically (every 4 days) by chemical analysis (Peroxide value (PV), thiobarbituric acid (TBA) and free fatty acid (FFA). Results showed that the fennel extract and BHT could reduce lipid oxidation in the samples compared to the control.  Moreover, minced silver carp treated with 1.5% fennel extract showed the lowest amount of lipid oxidation. The results indicated that fennel extract was improving the quality characteristics of treated fresh minced fish.

Application of garlic oil in food industry can be improved by encapsulation. There is no study about the formation of inclusion complex of garlic oil by beta-cyclodextrin. The aim of the present study is comparison of the antioxidant and antibacterial activities of free and encapsulated garlic oil with beta-cyclodextrin.

Antioxidant activity was determined by 1, 1- diphenyl-2- picryl-hydrazyl assay, and antibacterial properties by agar well diffusion, minimum inhibitory concentration, minimum bactericidal concentration and bacterial growth assay. Statistical analysis was performed by Minitab statistical software.
Results and

Garlic oil had poor antioxidant activity (EC50, 5222 µg ml-1 ) and EC50 because garlic oil/beta-cyclodextrin (containing 1495 µg ml-1 released garlic oil) was achieved after 5 h and 25 min. Agar well diffusion showed no inhibition zone on Muller Hinton Agar for garlic oil and garlic oil/betacyclodextrin (with initial release (shaking at 150 rpm for 24 h at 37ºC) and without initial release). Staphylococcus aureus was the most susceptible bacterium to garlic oil, and garlic oil/beta-cyclodextrin with and without initial release (minimum inhibitory concentration 10-5 , 10-4 and 10-3 % w v -1 , respectively); however, Bacillus cereus was the most resistant. The effect of initial release for garlic oil/betacyclodextrin on inhibiting the growth of all four bacteria was significant. There was no significant difference (P>0.05) between the inhibitory effect of garlic oil and garlic oil/beta-cyclodextrin with initial release on Staphylococcus aureus and Bacillus cereus, also Salmonella entrica and Escherichia coli. Garlic oil showed a weak antioxidant activity in 1, 1- diphenyl-2-picryl-hydrazyl assay. Garlic oil and its complex were not able to penetrate to the solid media; therefore, no inhibition zone and no antibacterial activity in the agar well diffusion assay were observed. Initial release of garlic oil/beta-cyclodextrin had significant impact on the inhibition of four bacterial growth, similar to free garlic oil. Since encapsulation of garlic oil can cover its drawbacks (low solubility in water, liquid form, and intense odor), garlic oil/beta-cyclodextrin could be considered as an nonsynthetic antibacterial agent.

Recently, due to the interest of healthy lifestyle demand for research on novel methods of increasing the shelf-life of food products without the necessity of using preservatives has extended rapidly in the world. Ability of nanoemulsions to improve global food quality has attracted great attention in food preservation. This is as a result of a number of attributes peculiar to nanoemulsions such as optical clarity, ease of preparation, thermodynamic stability and increased surface area. This review discusses the potential food applications of nanoemulsions as vehicles for the delivery of antimicrobial compounds. Moreover, the preparation, structure, and functional properties of nanoemulsions and their antimicrobial effects on foodborne pathogens and biofilms will be reviewed in detail. Antimicrobial nanoemulsions are formulated from the antimicrobial compounds that are approved by the Food and Drug Administration (FDA) for use in foods.
Results and The antimicrobial activity of nanoemulsions is nonspecific, unlike that of antibiotics, thus they have a broad-spectrum of antimicrobial activity against bacteria (e.g., Escherichia coli, Salmonella, and Staphylococcus aureus), enveloped viruses (e.g., HIV, and herpes simplex), fungi (e.g., Candida, Dermatophytes), and spores (e.g., anthrax) at concentrations that are nontoxic in animals (while limiting the capacity for the generation of resistance) and kill pathogens by interacting with their membranes. This physical kill-on-contact mechanism significantly reduces the possibility of the emergence of resistant strains. In general, more research is needed to improve the application processes of antimicrobial nanoemulsion, especially sensory aspects, to be appropriate for each product.
Conflict of interests: The authors declare no conflict of interest.

Hyssopus officinalis L. is one of the most important medicinal plants. Medicinal herbs arecontaminated by microorganisms. Conventional methods for reducing of microbial loads such as ethylene oxide, propylene oxide and also use of steam are hazardous and instead, non-thermal process such as microwave and gamma radiation are being used widely in order to eliminate the microbial contaminations with no or a little side effect. In the present study the effect of gamma and microwave irradiation on antioxidant and antimicrobial activities of Hyssopus officinalis L. was investigated. Hyssopus samples were exposed to gamma irradiation at doses 10, 15, 20 and 25 kGy and microwave irradiation at power of 300, 450 and 600 W for 5 min. In order to undergo the sequence experiments, the hydroalcoholic (EtOH 50%) extracts of plant were prepared. The antioxidant activities of irradiated and control samples were evaluated by DPPH radical scavenging (RS), ferric reducing power (FRP), β-carotene bleaching (BCB) and total phenolic content (TPC) of sampels. In order to study the antimicrobial activity, for determination of minimal inhibitory concentration (MIC) on E. coli and S. aureus, broth diluting method was used. Results showed that gamma irradiation had no significant effect on antioxidant parameters, phenolic content and antimicrobial activities of sampels. Microwave treatment of Hyssopus at 300, 450 and 600 W for 5 min increased its antioxidant and antimicrobial activities. Results indicated that gamma and microwave irradiation do not have any negative effect on antioxidant and antimicrobial activities of Hyssopus.

Tannase has several important applications in food, feed, chemical and pharmaceutical industries. In the present study, production of tannase by mutant strain, Penicillium sp. EZ-ZH390, was optimized in submerged fermentation utilizing two statistical approaches. At first step, a one factor at a time design was employed to screen the preferable nutriments (carbon and nitrogen sources of the medium) to produce tannase. Screening of the carbon source resulted in the production of 10.74 U/mL of tannase in 72 h in the presence of 14% raspberry leaves powder. A 1.99-fold increase in tannase production was achieved upon further screening of the nitrogen source (in the presence of 1.2% ammonium nitrate). Then the culture condition variables were studied by the response surface methodology using a central composite design. The results showed that temperature of 30°C rotation rate of 85 rpm and fermentation time 24h led to increased tannase production. At these conditions, tannase activity reached to 21.77 U/mL, and tannase productivity was at least 3.55 times (0.26 U/mL.h) in compare to those reported in the literature. The present study showed that, at the optimum conditions, Penicillium sp. EZ-ZH390 is an excellent strain for use in the efficient production of tannase.

Virgin olive oil due to having unsaturated fatty acids is exposed to various types of corruptions such as enzymatic reactions and lipid oxidation. One way to prevent oxidation of oils and fats is addition of antioxidants. Rosemary due to phenolic compounds and other antioxidant compounds have antioxidant as well. In this study, the extraction phenolic compounds of rosemary leaves in virgin olive oil with was performed using by ultrasonic technique. In this method, rosemary leaves with three levels (5, 7 and 10%) and three ultrasonic times (10, 15 and 20 minutes) were added to the olive oil. Phenolic compounds present in the extracts, was measured. The results showed that in the ultrasonic method the sample of virgin olive oil with 10% rosemary and 10 minute extraction time has the highest total polyphenols (457.59 ppm). In this case study the effect of this extract in retarding oxidation of virgin olive oil during the 4-month by determining the peroxide value, thiobarbituric acid, oxidative stability, at the end of each month were reviewed. After four months keeping, the ultrasonic's peroxide number, the thiobarbituric acid (20.75meq O2/kg oil, 1.32 molonaldehyde/kg oil, respectively) significantly decreased. The results of antioxidant activity of the extracts using rancimat method showed that during the period of induction at 110 °C in the ultrasonic's sample (29.10 hours) with respect to control's sample (6.28 hours) are increased. The acidity value of the ultrasonic's sample (2.05 FFA %) and thermal's sample (1.84 FFA %) are less than the control's (3.18 FFA %). Measurement results showed that the amount of chlorophyll pigments within ultrasonic's sample (1.4mg/kg) had the highest value and with respect to control's sample (0.63mg/kg) had high value. Also in the sensory evaluation, the ultrasonic's sample has top rated in terms of taste, odor, bitter and won general acceptance. Therefore, the phenolic compounds in the olive oil containing rosemary and extracted by ultrasonic method, be able to retard the oxidation process well. Thus, rosemary can be recommended as a source of natural antioxidants for increase virgin olive oil oxidative stability.

Recently there has been a tendency towards natural antioxidants due to the undesirable effects of synthetic antioxidants. In the present study Ultrasonic and Thermal methods were used to extract the components of Red Pepper (Capsicum annuum). In the first section of the research, in order to evaluate the treatment with the highest percentage extraction of phenolic compounds in Ultrasonic method, two factors, time (10, 15 and 20 minutes) and a pepper to oil ratio (5, 7 and 10%) were used. In the Thermal Extraction Method, pepper to oil ratio (5, 7 and 10%) was assessed with constant time factor (60 minutes in 80 ºC). Amount of phenolic components were measured by Folin–Ciocalteu method. Phenolic components of ultrasonic and thermal sample were determined 314.61 and 272.55 respectively. Retarding effect of treatments on the oxidation of virgin olive oils were studied through measuring of acidity index, Thiobarbituric acid number and evaluating thermal stability (Rancimat) and polyphenol content by keeping them in ambient temperature for four months. After four months, both the Ultrasonic sample and Thermal sample showed less peroxide (23 and 20/33 meq O2/kg oil respectively) compared to the control sample (35 meq O2/kg oil). Thiobarbituric acid, that indicate secondary oxidation products, showed a decrease in Ultrasonic and Thermal samples (0/28 and 0/20 respectively) compared to the control sample (0/33) at the end of period. The result from assessing the antioxidant activity of extracts by Rancimat method showed that the length of induction period in Ultrasonic and thermal samples (12/48 and 13/26 respectively) were increased compared to the control sample at 110 ºC. At the end of the four months, It was proved that Phenolic components of pepper in virgin olive oil has an antioxidant effect, and Ultrasonic treatment of red pepper extract compared to thermal treatment, has more antioxidant effect.

We studied the antioxidant activities of the essential oils of Zataria multiflora Boiss. (ZEO) and Bunium persicum (Boiss.) B. Fedtsch (BEO) in mixed form on linseed oil using (DPPH•), (ABTS•), H2O2 scavenging, and reducing power assays. After calculation of IC50 for ZEO and BEO separately, interactions of the essential oils were investigated at the form of mixture and the results were given in isobologram. The interactions between antioxidant effects of ZEO, BEO, TBHQ, and α-tocopherol; and isobologram results showed synergistic effect for DPPH• except for BEO with TBHQ and α-tocopherol (1:1) and for ABTS• in ZEO with TBHQ (1:1). However, we could not find any synergistic effect for H2O2 scavenging and reducing power assays in any of the interactions. Statistical results showed that the best antioxidant levels of reductive oxidation were 600 ppm for ZEO and BEO, and 20 ppm for TBHQ in mixed form in linseed oil.

Olive oil is a valuable and popular oil among the oils consumed and the demand for its production and consumption is increasing continuously. Therefore, the purpose of this study is to evaluate the effect of refining operation on the physico-chemical characteristics of virgin and refined olive oils. Two olive cultivars (Bladi and Arbequina) were collected from Fadak Farm (Iran – Qom region). The oils were extracted, bleached and deodorised using two different conditions. The first batch was bleached and deodorized at 50 for 30 minutes and the second batch was bleached at 70 and deodorized at 135 for 45 minutes. Tests concerned with the determination of fatty acid composition, free fatty acid content, peroxide value, conjugated dienes and trienes, total poly phenols, colour and induction periods were carried out on the oils. The results indicated that moisture, oil content of whole fruit, kernel and pulp were significantly different. Fatty acid compositions were not affected after the two treatment methods with the exception of Bladi variety that slight changes concerned with saturated and unsaturated acids occurred. The total polyphenols in Bladi and Arbequina varieties in the first treatment were 51.87% and 34.92% and in the second treatment were 68.67% and 92.67%, respectively. Conjugated dienes and trienes for each sample after the treatment decreased and increased respectively and the change after the second treatment was higher. The application of higher temperature for longer period affected both oils qualitatively. However the changes in acidity and peroxide values were similar.

Omega-3 fatty acids (FAs) have been shown to prevent cardiovascular disease. The most commonly used omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are highly vulnerable to oxidation and therefore, have short shelf life. Recent advances in nanoliposomes provided a biocompatible system for stabilizing omega-3 FAs. Several methods could be implemented to prepare nanoliposomes. To the best of our knowledge, the performances of these methods in preparation omega-3 FAs have not been examined. Nanoliposomes were prepared by thin film hydration followed by one of the following 1- extrusion, ultrasonic irradiation; 2- bath sonication; 3- probe sonication; or 4- combined probe and bath sonication. The size of liposomes obtained from methods 1 to 4 were 99.7 ± 3.5, 381.2 ± 7.8, 90.1 ± 2.3, and 87.1± 4.10 nm with ξ potential being -42.4 ± 1.7, -36.3 ± 1.6, -43.8 ± 2.4, and 31.6 ± 1.9 mV, respectively. The encapsulation efficiency (EE) for DHA was 13.2 ± 1.1%, 26.7 ± 1.9%, 56.9 ± 5.2%, and 51.8 ± 3.8% for methods 1 to 4, respectively. The corresponding levels for EPA were 6.5 ± 1.3%, 18.1 ± 2.3%, 38.6 ± 1.8%, and 38 ± 3.7%, respectively. The EE for DHA and EPA of liposomes for both methods 3 and 4 increased significantly (p < 0.05). Propanal, as the major volatile product formed during liposomal preparations, amounts from 81.2 ± 4.1 to 118.8 ± 2.3 µgg-1.

Pomegranate fruit is a rich source of bioactive compounds. The serious concern over unprocessed fruit juices is microbial contamination, which effectively inactivated by thermal processing, but it significantly affects juice functional compounds. Therefore, the effect of gamma irradiation and ultrasonic on inoculated microbial to pomegranate juices was studied.

Two pomegranate cultivars were purchased from the Agricultural Research Center of Saveh, and their juices were extracted by a manual device and immediately centrifuged. Then the studied microorganisms were resuspended in sterile pomegranate juices. The juices were continuously sonicated at amplitude levels of 50, 75 and 100% and times of 0, 3, 6, 9, 12 and 15 min at temperature of 25 ± 1°C. Irradiation treatment was also carried out at various doses of 0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3 kGy.

The results showed that lower amplitude levels (50 and 75%) did not inactivate E. coli and S. cerevisiae significantly (<1.5 log reduction), while at 100% amplitude level for 15 min, their population reduced by 3.47 and 1.86 log cfu/mL, respectively. Gamma irradiation treatment at 1 kGy also reduced E. coli by 6.66 log cfu/mL, whereas at 3 kGy it reduced S. cerevisiae by 5.08 log cfu/mL.

The low-dose gamma irradiation could potentially inactivate the studied microorganisms compared to the sonication, which had less destructive effects on their populations. Further research is needed to determine the effect of these methods on other fruit juices for industry purposes.

Tannase can be obtained from the various sources for example tannin rich plants; however microbial sources are preferred for industrial production. In microbial sources, the Aspergillus and Penicillium genus and lactic acid bacteria mostly produce tannase. However, it has been identified that this enzyme is produced by many fungi and bacteria, but researches are continuing to find new species.. The aim of this study was to isolate a tannase-producing fungi from moldy tea leaves and to study some properties of its enzyme.. The present study was done via two steps. At first, industrially important tannaseproducing fungi were isolated from moldy tea leaves using the simple agar plate method followed by the screening of organisms capable of producing tannase using the enrichment culture technique in modified Czapek Dox’s agar. Finally, tannase obtained from the best isolate was partially purified and characterized.. Tannase produced by Penicillium sp. EZ-ZH190 isolated from moldy tea leaves was partially purified and characterized. Maximum enzyme production (4.33 U.mL-1) was recorded after 96 hours of incubation at 30 °C in submerged culture (100 rpm) utilizing 1% (w/v) tannic acid as a sole carbon source. This tannase exhibited optimum activity at 35 °C and at pH of 5.5, and showed nearly 50% of its maximal activity at 50 °C. In the present study, tannase from Penicillium sp. EZ-ZH190 had KM and Vmax values of 1.24 mM and 17.09 U.mL-1, respectively, and showed more than 50% stability at salt (NaCl) concentration of 1 M for 24 hours.. Tannase productivity of Penicillium sp. EZ-ZH190 (0.045 U.mL-1.h-1) is comparable with the maximum tannase productivity in the reported literatures, and the biochemical characteristics showed by Penicillium sp. EZ-ZH190 tannase are considered favorable for tannin biodegradation in the industry. So, we concluded that Penicillium sp. EZ-ZH190 is a good strain for use in the efficient production of tannase..

Oxidation of oils has an important effect on nutritional and organoleptic properties of foodstuffs. Nowadays, new tendency has created a necessity to use natural compounds such as essential oils for producing functional foods. In this study, antioxidant, antifungal, and organoleptic properties of Zataria multiflora Boiss.(ZMEO) and Cinnamon zeylanicum essential oils (CZEO) have been checked as two natural preservatives in the cakes.

The antioxidant activity of essential oils were determined by measuring thiobarbituric, peroxide, and free fatty acid values of prepared cakes during 60 days storage at 25˚C. Antifungal properties of essential oils were determined and given as the ratio of colony number in samples containing ZMEO and CZEO to the control.

Different concentrations of essential oils prevented oxidation rate and reducd preliminary and secondary oxidation products compared with butylate hydroxyanisole (BHA (100 and 200 ppm)) and control cakes. Moreover, ZMEO and CZEO at three concentrations (500, 1000, and 1500 ppm) reduced the fungal growth more than samples containing BHA (100 and 200 ppm) and the control.

Our results showed that optimum concenteration of ZMEO and CZEO for using in the cakes was 500 ppm therefore it can be replaced instead of synthetic preservatives in foodstuffs.

Essential oils of medicinal plants such as chamomile are very complex natural mixtures which can contain compounds at quite different concentrations and some of their components have antioxidant and antimicrobial activities in foodstuff. The antioxidant and antimicrobial effects of chamomile essential oil in cake preparation were evaluated during 75 days of storage. Cake were produced: cakes were treated with chamomile essential oil in three levels (0. 05%، 0. 1%، 0. 15%)، cakes were not treated with synthetic and natural antioxidant and antimicrobial agents، and a commercial cake containing synthetic antioxidant (tert butyl hydro quinine= TBHQ) and antimicrobial (potassium sorbate) agents. In all samples peroxide value، thiobarbitoric value، acidity، microbial test (yeast and mould) and sensory test (color، flavor، texture، taste and overall quality) were determined at time intervals 1، 7، 15، 30، 40، 60 and 75 days. Statistical results showed that، the sample containing chamomile at 0. 15%، had good antioxidant and antimicrobial activity in comparison with the control samples (without any synthetic and natural antioxidant and antimicrobial agents) (p<0. 01). But its activity was less than that of synthetic ones (TBHQ and potassium sorbate as antioxidant and antimicrobial agent) (p<0. 01). In sensory evaluation، the sample containing chamomile at 0. 05% had higher score in flavor، taste and overall acceptability than the samples at 0. 15 and 0. 1% (p<0. 05). Chamomile essential oil as a natural antioxidant and antimicrobial agent can increase shelf-life of food products and due to absence of synthetic agents are safe with no side effect on human health.

Oxidation of lipids causes reduction of different properties of products that contains lipids. Nowadays, there is a growing demand for the natural antioxidants due to the harmful effects of synthetic antioxidants such as BHA, BHT and TBHQ. In this study, extract of aerial parts of Echinacea purpurea L. was used instead of synthetic antioxidants in cake then, antioxidant and antifungal activity of Echinacea purpurea L. extract (EPE) were evaluated in cake. The antioxidant activity of EPE and synthetic antioxidant was compared by measuring peroxide and thiobarbituric acid values during 60 days storage at 25 ºC. Antimicrobial properties of EPE were evaluated by counting of molds in Dicholoran Glycerol agar (DG18%) medium and free fatty acid analyses were assessed by IUPAC method. The effect of the extract on the color, texture, taste and total acceptability of the cake samples was carried out by a group of 20 trained panelists using Hedonic test. Different levels of EPE were able to retard the oxidation rate of cake, the 1000 ppm of it showed the lowest PV and the antioxidant activity of EPE was higher than BHA 200 ppm (p<0.01). EPE at 1500 and 2000 ppm showed the best antimicrobial activity (p<0.01). Cakes which containing the extract were well acceptable in terms of sensory parameters. Results showed that EPE was more effective in controlling growing molds and lipid oxidation during 60 days storage at 25 ºC and it can be used instead of synthetic antioxidant and preservatives.

Because of some adverse effect of chemical food additives such as synthetic antioxidants, it has been considered by researchers to replacing these materials by natural products. To measure the total phenolic content of Malva sylvestris extract (MSE); to evaluate the antiradical activity of this extract by DPPH°, ABTS°+ and β-carotene bleaching methods (BCB) and to study its application as natural antioxidant in soybean oil. Total phenolic content (TPC) of MSE was determined by Folin- Ciocalteau method. Antiradical activity was measured by DPPH°, ABTS°+ and BCB methods and compared with synthetic antioxidant BHA. The antioxidant activity of extract was studied in soybean oil (oven test at 70 oC) by measuring peroxide value (PV), thiobarbituric acid value (TBA) and conjugated diene (CD) and compared with BHA and BHT (at two level 100 and 200 ppm). MSE was possess 4.5% phenolic compounds in base of dry matter. In DPPH° assay, EC50 of MSE was 0.37 ± 0.01 mg/ml. In ABTS°+ assay, maximum antioxidant activity was related to 5 mg/ml concentration of MSE (70% inhibition). In BCB test, maximum antioxidant activity of 0.05 – 10 mg/ml concentration of MSE was related to its 10 mg/ml concentration of it (52.6 %). This extract could retard oxidation process of soybean oil at 400 ppm that was almost equal to BHA at 100 ppm. MSE showed antiradical activity and it seems it can be applied as natural antioxidant in foods containing edible oils.

It has been considered by researchers to study the possibility of replacing chemical food additives such as synthetic antioxidants by natural products especially medicinal plants. The aims of this study were as follow: (i) to determine the major components of the essential oil of Lavandula angustifolia. (ii) to evaluate the antiradical activities of this essential oil by DPPH°, ABTS°+ and β-carotene bleaching assays and (iii) to evaluate the antioxidant activity of this essential oil in crude soybean oil. The main chemical components of essential oil were identified by GC/MS. Antiradical activities of mentioned essential oil was measured by different methods and finally, its antioxidant activity was determined in crude soybean oil system by Oven method. Six main compounds were identified: linalool (27.89%), camphore (10.82%), 1, 8 cineol (9.05%), inalol acetate (8.86%), borneol (7.29%) and α-terpineol (5.04%). EC50 of essential oil was 35.54 ± 1.58 mg/ml. In ABTS°+ assay, maximum antioxidant activity was related to 40 mg/ml concentration of essential oil. In β-carotene bleaching assay, maximum antioxidant activity of essential oil was related to the 10 mg/ml concentration of it (54.4 percent radical scavenging activity). In oven test, essential oil could inhibit of primary and secondary oxidation products of crude soybean oil at 0.8 mg/ml that was almost equal to BHA at 0.2 mg/ml. Antiradical activity of essential oil of Lavandula angustifolia was proved and it seems that after complementary examination, it can be used as natural antioxidant in food, especially those containing edible oils.

Although the importance of ω-3 and ω-6 essential fatty acid has been known but functional and physiological properties of ω-3 and ω-6 fatty acid are different. The balance use of ω-3 and ω-6 fatty acid is more important because in vivo cant make them. Possibility production of the functional oil from vegetable sources such as flaxseed (containing ω-3) and safflower (containing ω-6) oils including extraction, formulation and preservation. After extraction of the oils from flaxseed and safflower, physicochemical properties of the oils were examined and the product underwent the fractionation process in order to increase the ω-3 ratio. Then, functional oil was formulated using a 1:1 mixture of ω-3 and ω-6. Storage conditions and stability of the oil were also investigated for four months (0, 1, 2, 3 and 4 months) by studying peroxide, thiobarbituric acid and Rancimat indexes. Results showed that the ω-3 ratio may be increased from 50.19 to 52.59% (p<0.05) through fractionation. During the storage of the functional oil in the four months, the peroxide index increased from zero to 100.43 and 4.99 (meq O2 /k oil), the thiobarbituric acid index also increased from zero to 4.99 and 0.026 (malondialdehyde mg /k oil), and the Rancimat index decreased from 2.10 to 0.33 and from 2.10 to 1.35 (p<0.05) in the refrigerator and freezer, respectively. With the fractionation process can increase the amount of ω-3 fatty acid about 4/78 percent (p<0.05). Diagnostic examination showed that during the storage of the functional oil peroxide value of oil were under standard, so recommended using refrigerator in order to preserve functional oils.

Nowadays, there's a growing demand for the natural antioxidants due to the harmful effects of synthetic antioxidants. Therefore, introduction of new natural antioxidants (especially those with plant origin) is very important. The present study explores the chemical constitution and antioxidant activity of leaf extract of Hyssopus officinalis L. and extract of aerial parts of Echinacea purpurea L., as two valuable natural antioxidants in soybean oil. Total phenolic content of the water extract of Hyssopus officinalis L. and Echinacea purpurea L. were determined by Folin–Ciocalteu method. The antioxidant activity (AOA) of these two extracts were evaluated with DPPH•, ABTS•+ and beta carotene bleaching (BCB) methods. Furthur, the oven tests including peroxide and thiobarbituric acid values were done at 70º C in soybean oil system. Total phenolic content of Hyssopus officinalis L. and Echinacea purpurea L. were 200 and 60 mg/g phenolic components (galic acid equivalent), respectively. In DPPH• test, EC50 value of Hyssopus officinalis L. and Echinacea purpurea L. were 35.6± 4.7 and 123.0± 10.9 ppm, respectively. In the oven test (in soybean oil), AOA of all concentrations of HOE was comparable to BHT and BHA at the concentration of 100 ppm. AOA of EPE was comparable to BHT at concentrations of 100 and 200 ppm, but lower than that of BHA. In all three DPPH•, ABTS•+ and beta carotene bleaching tests, the antioxidant activity of Hyssopus officinalis extract (HOE) was greater than that of Echinacea purpurea extract (EPE). The antioxidant activity of both extracts improved with increase of the concentration. Further, HOE and EPE were able to reduce the oxidation rate of soybean oil under conditions of the oven test at 70° C. Thus, these two extracts could be appropriate natural alternatives to synthetic antioxidants.

A group of the natural antioxidants is the polyphenols in green tea leave extracts (GTE). In this research، the extraction of antioxidants from the leaves was done with aqueous solution and then the extract was purified and finally dried and made into powder. Then the antioxidant effects of produced powder and α -tocopherol at 200 and 500 ppm، butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) at 100 and 200 ppm، and the combination synergistic effect of mixtures: 200 ppm GTE+500 ppm α -tocopherol، 500 ppm GTE+200 ppm BHA and 500 ppm GTE+200 ppm BHT in two types of sunflower oil (with and without citric acid as a chelator) at 50oC and time intervals of 0، 5، 8، 12 days were examined and compared for peroxide value (PV) and thiobarbituric acid (TBA) test. Results showed that the individually antioxidant effect of GTE at both concentrations was better than that of other antioxidants. Combination of GTE+BHT demonstrated antagonistic effect but no remarkable synergism or antagonisim was observed in other combinations.