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In this research, the effect of vacuum pressure and storage time were investigated on the postharvest quality of tomato and carrot. Three levels of vacuum pressure, 0.6, 0.4 and 0.2 bar were considered and during 12 days of carrot storage every three days and during 20 days of tomato storage every five days the sampling were performed. The effects of these treatments on the factors such as weight loss, firmness, soluble solids, titrable acidity and pH in carrots and tomatoes were investigated as factorial test based on Completely Randomized Design. Analysis of variance results showed that the effect of vacuum pressure and storage time on all mentioned factors were significant. Weight loss of both products was low at vacuum pressure of 0.4 bar. Also, tirable acidity and pH of these products were preserved better at vacuum pressure of 0.4 bar. The highest firmness was observed at vacuum pressure of 0.4 bar. Based on the results, storage of these two products at high vacuum pressure (0.6 bar) reduced the quality. In general, vacuum pressure of 0.4 bar was resulted in higher storage time of tomato and carrot.

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Time-temperature indicators (TTIs) are used to check the safety of the fresh foods with reduced oxygen packaging (ROP). Already, the behavior of TTIs with zero-order kinetic was described based on Skinner-Larkin model. For TTI expiration before toxin formation, the Arrhenius curve of TTI (in the coordinates system of lnk versus 1/T) should be located above the zero-order Skinner-Larkin-Arrhenius curve (SLA0) for all possible temperatures. However, SLA0 may incorrectly describe TTIs behaviors since they often provide first-order kinetic (similar to most natural processes). Developing a new model to describe the behavior of all types of TTIs (with zero or first-order kinetic) for fresh seafoods with ROP is the main goal of this research. In this paper, the first-order Skinner-Larkin-Arrhenius (SLA1) model is proposed as a pencil of curves to extend SLA0 for the TTIs with first-order kinetic. Furthermore, because of including the SLA0 curve, the SLA1 model can be equivalently used for both zero-order and first-order TTIs. Simulation results demonstrated that SLA0 could not correctly predict the behavior of first-order TTIs. By using the proposed model, we can successfully predict the behavior of both zero-order and first-order TTIs for fresh seafoods with ROP. 

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  Freshness of vegetables and fruits in the short term and long term is one of the important challenges of postharvest process. In this research, the effects of packaging type, modified atmosphere and temperature on the post harvest quality of tomato were investigated during storage. The treatments were considered as modified atmosphere packaging (passive and active) with two gas combinations (4%O₂+8%CO₂+88%N₂ and 8%O₂+4%CO₂+88%N₂), two types of package (polypropylene and polyethylene films) and two storage temperatures (4±1) and (20±2)ºC. The effects of above mentioned treatments were investigated using Completely Randomized Design with three replicates on the weight loss, firmness, soluble solids, titratable acidity and pH of tomato during 20 days storage. Analysis of variance results indicated that the effects of all treatments on the measured factors were significant (p<0.01). Tomatoes stored in polypropylene due to less thickness and more O₂ permeability preserved the quality of tomatoes better than those of polyethylene film.Also,storage temperature of(4±1)ºC maintained the quality of tomato much better than (20±2)ºCdue to slow down metabolic activities. The first gas combination (4%O₂+8%CO₂+88%N₂) was suitable due to higher CO₂ and respiration reduction. Tomatoes stored in polypropylene film and first gas combination at (4±1)ºC had the best quality after 20 days storage. In general, storage of products in the packages with modified atmosphere resulted in preserving quality and shelf life.  

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  The aim of the study was to evaluate antimicrobial effect of extract of Lamiaceae plants (Thymus vulgaris L., Mentha spp. and Ziziphora tenuir L.) to prevent growth of pathogenic bacteria (Staphylococcus aureus, Geotrichum candidium) was studied  industrial Doogh samples. For this purpose, three levels of concentration of extract that containing (0, 0.075, 0.15 v/v) was prepared. Survival or decrease in the bacterial population in 40 treatments (3 times repeated) in the samples of sterilized Doogh, which that contain a suspension of pure specific strains of Staphylococcus and Geotrichum in the during 24 hours and 14 days by measuring the kinetics of bacterial pathogens was investigated using response surface design. Analysis Results in the inhibition effects of natural antibiotic agent in the Doogh samples revealed that  concentrations of thymus extract % 0.14 (v/v) , Mentha oil % 0.11 (v/v) and Ziziphora oil % 0(v/v)  is the inoculation rate, which in most circumstances Reduction Staphylococcus aureus in 24 h 2.84Log/ml, 7 days in the 1.63 Log/ml

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Today, many studies are doing to identify the lipolytic microorganisms because of the important role of them in the production of microbial lipases. Oilseed meals are a good place to achieve these microorganisms. In this field, yeasts are more important in comparison with other microorganisms. In this study, we isolated 27 types of fungi from Yazd sesame meal. After the evaluation of macro and micro morphological features, it was identified that 16 of them were from yeast group. Lipolytic yeasts were screened using Tween 80 agar medium and were identified to genus and species by colony and cell morphology observations and evaluation of fermentation reactions and the use of carbon and nitrogen sources. 4 lipolytic  screened  yeasts were included Sporidiobolus pararoseus, Sporobolomyces salmonicolor, Cryptococcus albidus and Yarrowia lipolytica .The ratio of areola diameter to the well diameter was  between 2.314 – 2.714. S. pararoseus showed  the maximum ratio of areola to well diameter (2.714) .Lipase activity of these four types of yeasts was measured in submerged cultures with Cezepek Dox medium for 7 days at 30 °C and 200 rpm by using of photometry method and p-nitrophenyl palmitate substrate. Lipase activity range was between 0.866 – 4.333 U/ml, and Cryptococcus albidus had the highest lipase activity 4.333 U / ml, while it showed the least biomass growth among other yeasts (OD= 0.577). Yarrowia lipolytica showed lipase activity of 3.466 U/ml and also, the highest biomass growth OD =0.806.  

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  The aim of this work was identified lactic floraas a traditional fermented food and then evaluates antimicrobial activities of some strains. A total of 140 Gram-positive and catalase-negative isolates were subjected to grouping by physiological and biochemical tests and carbohydrates fermentation. Based on the resultsthese 140 isolateswere dividedinto 9 groups. Two or three isolated were selected from each group and 16S rRNA was amplified using universal primers. Diversity of lactic acid bacteria in horreh was as followings:Lactobacillus fermentum (30.00%),Lactobacillus plantarum (28.57%), Lactobacillus brevis (15.00%), Weissellacibaria(8.57%),Enterococcus (faecium and faecalis) (7.14 %), Leuconostoc (citreumand mesenteroides subsp.Mesenteroides) (6.42%) and Pediococcus pentosaceus (4.28%). Antagonistic activity of 20 isolates (strains) of lactic acid bacteriaobtained fromhorreh was evaluated against food- borne bacteria. Sixteen isolates in Agar spot method and 14 isolates in well diffusion assayshowed antibacterial activity against at least one of these indicators. Eight isolates including:Ent. faecium (1), Ent. faecalis (1), P. pentosaceus(1) and Lb. plantarum (2) exhibited  the  highest  antagonistic  activity toward Listeria innocoa. Antagonistic activity of cell free supernatant (CFS) from Lb. plantarum showed the highest thermal stability. Also, two isolates belonging to:Ent. faecium, Ent. Faecalis presented antibacterial activity at pH=7. Only, the supernatant of Lb. plantarum was not influenced by proteinase K.The results showed that the supernatant of some isolatestestedcan be used as a bio preservative in food products.

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The purpose of this study was to evaluate the effect of time, kind of extract, extract concentration and temperature on the dynamically the population of Escherichia coli (infectious agents) in the complex food system (frankfurter sausage) and Genetic Algorithm - Artificial neural network and neuro fuzzy system (CANFIS) were used for dynamic modeling of population of E.coli. At this research laboratory, Minimum Inhibitory Concentration (MIC (and Minimum Bactericidal Concentration (MBC) of aqueous and ethanolic extracts were studied using the micro broth dilution method. GA- ANN, neuro fuzzy (CANFIS) were fed with four inputs: concentration at the five level (0, 2000, 4000, 6000, 8000 ppm), kind of extract ( watery, ethanol), temperature at the three level (5,15, 25  ̊С) and time (1-20). The results showed that the ANN with 1 hidden layer comprising 10 neurons, Tangent hyperbolic function, momentum training rule and percent of used data 30/30/40 for training/cross validation/testing respectively gives the best fitting with the experimental data, which made it possible to predict with high determination coefficient (R2 equal to 0.995). Also the correlation between CANFIS predictions and experimental data was very good (R2 equal to 0.96). It's worth to mention that in this research GA- ANN was better approach to simulation dynamically the population of E.coli.

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Kimchi is a fermented herbal supplement, and appetizer that according to a raw material, process and geographical location are classified more than161 types. In this study, after kimchi production, isolation and identification of microorganisms was performed by molecular method. Lipase producing strain, Trichosporon asahii was isolated from kimchi sample (19.01 ±3 U/ml). The various medium components and culture parameters to achieve a more cost effective and economically viable bioprocess were screened and optimized using Design Expert software. PBdesignsare used to screen the most effective variables on lipase production that fermentation temperature and initial pHfor 48 hours 30 . According to the results, extract of nigella sativa, olive oil, yeast extract, magnesium chloride, respectively, were the most variable. Variable particle size and pepton ehavenegative effect. The variable selection and optimization on was performed more efficiently. Finally, lipase activity was 35 ± 0.5 U/ml in the optimal conditions using a medium containing15% sativa extract, 10 g/l yeast extract, 22.5 g/l olive oiland25 mM/l magnesium chloride in the rotation speed of 150 rpm, respectively, as well as enzyme activityafter84/1times the optimal state before optimization. The kinetic parameters V (max) and K (m) was 0.367 mM / min and 0.53 mM through Michaelis–Menten Chart, respectively. Low K_m indicates high affinity between enzyme and substrate and high V_max demonstrates high catalytic performance of the enzyme

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Kimchi is a general term for fermented vegetables.The aim of this study was to isolate and identify the Lactic Acid Bacteria involved in spontaneous fermentation of this product used biochemical and molecular methods. In this study, after successive culture on specific media, in order to classify of 85 selected isolates that according to preliminary experiments seemed Lactic Acid Bacteria, physiological and biochemical tests were done and then fermentation of 10 different carbohydrates were performed. Based on these tests, 85 isolates were divided into 10 groups. Some isolates were selected from each group and 16S rRNA was amplified using universal primers. Diversity of lactic acid bacteria in Kimichi was as followings: Lactobacillus plantarum (41.17%), Lactobacillus fermentum (9.41%), Enterococcus faecalis (3.52%), Enterococcus faecium (7.06%), Leuconostoc citreum (2.35%), Leuconostoc mesenteroides (3.52%), Pediococcus pentosaceus (8.23%), Wisella cibaria (24.70%). This fermented product has a wide microbial diversity which originates from natural microbiota presented in the raw vegetable. Lactic acid bacteria can produce a variety of acids and enzymes which play an important role in development of unique flavor and tasteTherefore, this strains that isolated from Kimchi can be used in the food industry.

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Infectious diseases created by strains of Antibiotic resistance Escherichia coli and Staphylococcus aureus, is increasing in many countries such as Iran. Therefore, many efforts are performing in order to find a new composition as replacement for antibiotics. In this experimental research, an antimicrobial effect of the ethanolic and aqueous extract of Hibiscus Sabdariffa was investigated on several strains of Escherichia coli and Staphylococcus aureus resistant to common clinical antibiotics.The extract of Hibiscus Sabdariffa was prepared using rotary. Twenty strains of Escherichia coli and Staphylococcus aureus were provided from Mashhad University of Medical Sciences. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using Serial Dilution Method in six concentrations onto strains of Escherichia coli and Staphylococcus aureus in broth media.The results showed that Escherichia coli was resistant to antibiotics of penicillin (75.9%), erythromycin (58.3%), tetracycline (56.9%), and cefixime (37%), and Staphylococcus aureus showed resistant to antibiotics of penicillin (83.5%), cefixime (80%), erythromycin (55.6%), and tetracycline (26.1%), respectively. Also, the ethanolic extract of Hibiscus Sabdariffa has acceptable effect on antibiotic resistant strains of Escherichia coli and Staphylococcus aureus that MIC of the Hibiscus Sabdariffa ethanolic extract was 4 and 16 mg/mL for Escherichia coli and Staphylococcus aureus, respectively.The overall, the Hibiscus Sabdariffa extract has inhibitory ability on Antibiotic resistant Escherichia coli and Staphylococcus aureus strains. So, the ethanolic and aqueous extract of Hibiscus tea can be used in in pharmaceutical industry for medical treatments with perfect study.

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  With emerging of infectious diseases and spread of antibiotic resistant strains, use of antimicrobial compounds with plant origin seems necessary. In this study, ethanolic extract of Cordia myxa fruit was used to evaluate antimicrobial effects against microorganisms including Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella typhi, Aspergillus niger and Candida albicans. Ultrasound-assisted extraction was performed to investigate three independent variables: time (5- 40 min), temperature (20- 50°C) and sonic power (20- 100%). Response surface methodology was also employed to optimize multiple variables to predict the best process conditions. Antimicrobial activity was done by methods including disk diffusion agar, pour-plate, minimum inhibition concentration and minimum bactericide (fungicide) concentration. The results showed that the highest amount of extraction rate of ethanolic extract which was equal to 8.5%, was obtained in extraction time of 39.8 min, temperature of 42.2°C and sonic power of 94.4%.In all above-mentioned methods, inhibitory effect of optimum ethanolic extract was more significant againstBacillus cereus, Staphylococcus aureus and Candida albicansthan other strains (p≤0.05).

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   Ice cream is a complex food colloid including fat droplet and air cells that dispersed on the relatively frosted aqueous phase. In this research work, the effect of the fat at the four level  ( 2.5, 5, 7.5, 10 % ) , pekmez  at the three level ( 0, 9, 18 %) ,  two types of hydrocolloids (Carboxyl Methyl Cellulose and balangu ) each at the four level ( 0.1, 0.3 ,0 .5 , 0.7 % ) on the viscous flow properties and total acceptance of  ice cream by response surface methodology (RSM) was investigated.  The flow behavior of all samples using Power law, Casson, Bingham and Herschel- Bulkley models was investigated. According to the R² (≥0.99) and RMSE (≤0.9314) values, it is obvious that the Power law model is highly appreciated for describe flow behavior of ice cream samples. Also the Result indicated that casson plastic model was highly significant for evaluate yield stress of ice cream samples. Samples containing Balangu gum has higher consistency coefficient and yield stress and lower flow behavior index than samples containing CMC. Its worth to mention that Herschel-Bulkley model gave negative values for yield stress which has no physical meaning. Balangu seed gum (BSG) in comparison to carboxyl methyl cellulose did not have a significant effect (P > 0.05) on the total acceptance. The Desirability function has been achieved as 0.93 which, itself, indicates the accuracy of optimization. The optimum formulation has been found as following: fat of 5.6%, BSG of 0.6% , Pekmez of 18%, respectively.

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    In this study to determine the effect of sonication time and intensity on the activity of the alpha-amylase, Aspergillus Oryzae PTCC 5164 as a Producer of enzyme was used in the solid staste fermentation system.  A combination of wheat and barley (0:100, 50:50, 100:0) as a substrate, Ultrasound with the intensity treatment (35, 5/67 and 100%) and 5, 10 and 15 minutes were used. Statistical analysis with software Design Expert 6.0.2 showed that the effect of ultrasound on enzyme produced in culture platform is different. Alpha-amylase production with barley as the substrate had more resistant during the sonication. Also by increasing the time and intensity of sonication, negative effects of cavition became more apparent and enzyme activity decreased. Diminishing activity of the alpha-amylase produced, depends on the duration and intensity of sonication and combination of solid culture. Probably the π₀ → π* amide transitions and secondary structural components, especially b-sheet, of the enzyme was significantly influenced by ultrasound.

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Yarrowia lipolytica is unusual yeast that has the ability to produce important metabolites such as lipase enzymes. Lipase enzyme has many applications in different industries including manufacturing of detergents, food industry, pharmacy, fuel and etc. In this paper, we studied the lipase enzyme produced by the yeast under different treatments of nitrogen sources such as yeast extract, peptone, soybean meal, sesame meal and sesame meal extracts on the medium of Czapek Dox Broth. Selected treatments of nitrogen resources include treatment solution (100%), solution (50%) containing with sesame cake extract (3.6%), solution (50%) containing with sesame cake extract (3.6%) in distilled water, solution (50%) containing with yeast extract (3.6%) in distilled water and solution (50%) containing with peptone (3.6%) in distilled water on the medium (CDB). Fermentation time levels are considered 3, 4 and 5 days. Among examined treatments, Treatment solution (50%) containing with sesame cake extract (3.6%) on the medium (CDB) showed the highest lipase activity (91.5900±0.56241 and 67.5200 ± 0.01000 enzyme units, respectively) in the fourth day of incubation with stirring speed (120 rpm) and temperature (30 °C). The results show use of sesame cake extract increases lipase activity more than use of yeast extract and peptone at the level of 5%. Also, statistical analysis of resulted data showed use of sesame cake extract increases lipase activity significantly at 5% level in comparison with yeast extract and peptone.

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  Studies have shown that camel milk and its fermented products have therapeutic properties and high nutritional value. Lactic acid bacteria play important role in Fermented dairy products. The aim of this study is to determine the lactobacillus community of camel milk. A total of 9 Lactobacillus were isolated from camel milk of Golestan province in Iran. The log₁₀ CFU of Lactobacillus per ml on MRS medium under anaerobic condition at 20, 37 and 45⁰C included 8.792± 0.14, 8.301±0.07 and 7.301±0.03 respectively. Isolates were identified on the basis of Biochemical and Phenotypic Characteristics as Lactobacillus paraplantarum, Lactobacillus ferintoshensis, Lactobacillus brevis, Lactobacillus pantheris, Lactobacillus johnsonii, Lactobacillus mali. Presence of Lactic acid bacteria was confirmed by band formation of PCR product in 1500 bp (amplification 16S rRNA gene using B27F-U1492Runiversal bacterial primer). Evaluation of their technological properties of isolates showed that isolated Lactobacillus fromcamelmilkhave lipoliticy, Proteolytic activity and high acidifying activity (except for Lb. mali and Lb. johnsonii). Also, allisolates, except Lb. Johnsonii, have autolytic activity in fair level. Based on technological properties ofisolates, Lb. paraplantarum, Lb. Brevis and Lb. pantheris are suggested as good candidates for camels milk processing or other fermentation process.  

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The lipase is used broadly in different industries such as food, drug, petroleum and detergent industry due to the catalyst ability of wide range of conversion reactions such as hydrolyzed, esterification and transesterification . Yeasts are one of the main generators of lipases. In this paper, we use RSM and CCD in order to examine the effect of PH (5.5-7.5), time incubator (3-7days) and sesame meal extracts added to experimental medium (0-100%) on lipase generation and activity, generated biomass of Cryptococcus albidusand optimization of lipase generation process and generated biomass. The results showed that the percentages of sesame meal extracts added to experimental medium and time incubator are the most effective factors on lipase generation and activity and amount of generated biomass, respectively. Based on conducted experiments, optimized conditions of lipase generation and amount of generated biomass are determined PH 5.56 time incubator 7 days and percentages of sesame meal extracts added to experimental medium 100 percent in order to achieve maximum lipase activity (98.96 unit enzyme) and cell dry weight (1.14 gram per 100 mili liter medium).

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