مجله میکروبیولوژی کاربردی در صنایع غذایی
سال دوم شماره 3 (پاییز 1395)

History of pickles dates back to the time of the Median people, in Iran, while only 70 years been passed in the industrial production of pickles. Winter Salad is a kind of pickle made of different vegetables that consumed specially in Khorasan province. The aim of this study was to investigate the effect of different levels of Jerusalem artichoke in Winter Salad formulation on biodiversity of product and determine some probiotic properties of Lactic Acid Bacteria strains. Winter Salads with three different levels of Jerusalem artichoke (contain 0%, 10% and 20%) were produced and the effect of this prebioticJerusalem artichoke contains inuline as prebiotic) on the gowth of lactic acid bacteria was studied in five interval times.Confirmatory tests include evaluation of acid resistance, evaluation of resistance to bile salts and evaluation of antibacterial activity, were performed to determine the probiotic characteristics of isolates. Results showed that, in early fermentation period, Lactic Acid Bacteria attended as part of the vegetables microbial population and lactic acid bacteria count increased by increasing the percentage of Jerusalem artichoke in products. The results indicated that Pediococcusand Lactobacillusshowed good probiotic propertiesamong evaluated isolates. Product fermentation until the twenty-first day was associated with a decrease in pH and an increase in lactic acid bacteria.

The aim of this study was to evaluate the antimicrobial properties of a dominant LAB isolated from barley sourdough and it’s cell free culture filtrate (CCF) as native and neutralized obtained from logarithmic and stationary phasesagainst some of foodborne bacteria (Escherichia coliStaphylococcus aureusListeria monocytogenesBacillus subtilis) and foodborne fungi (Aspergillus flavusAspergillus niger). After identification of LAB isolate by specific PCR, antimicrobial properties of the isolate and it’s CCF were investigated based on disc diffusion and microdilution (antibacterial) and overlay and agar spore spot (antifungal) methods, respectively. Sequencing results of PCR products lead to identification of Lactobacillus curieae,which hadsignificantly higher antagonistic effect on Lmonocytogenes in comparison to other indicator bacteria (PBsubtilis by 59.78% reduction of it’s survival. Furthermore, there was not significant different between antifungal activity of Lcurieae against Aflavus and Aniger (pAniger

In this study, the effect of starter culture, incubation temperature andfinal pH on the viability ofBifidobacterium lactis and Lactobacillus acidophilus, sensory characteristic and rheological properties of doogh were studied Samples were fermented at temperatures (37, 40 and 44C) till the pH value dropped to 46, 44 40 or 38 by two starters culture (ABY1 and ABY2) Statistical evaluation showed that the relationship between the variables listed and viability Probiotics were significant effect Compound treatment of ABY2 starter culture, incubation temperature of 37◦c and 46 and 44 for final pH resulted in highest viability of both probiotic bacterias final pH and incubation temperature exhibit a significant effect on flow behavior and particle size distribution, By reducing of pH from 46 to 4, increased the diameter of particles and then diameter of particles decreased with dropping of the pH to 38 Incubation temperature of 44°c to 40°c and 37°c increase the diameter of particles range and viscosity it changed mouthfeel as the Best flavor, mouthfeel and overall acceptability were observed at samples that were fermented at 44°c and Samples with the highest viability of Probiotic bacteria have lowest overall acceptance and the sensory properties of them was evaluated intermediate

In this study, some properties of biodegadable antimicrobial dextran based films for packing of food materials were evaluated. Therefore,biodegadable antimicrobial films based on dextran were made using chitosan, nisin, streptomycin and nanoparticles of PLGA and were compared with control samples. Analysis of thickness, light absorption, percent of transmittance, anti- microbial properties and permeability to oxygen and water vapor also were carried out. Also, elongation index was measured by texture analyzer. At the control samples and films containing chitosan and nisin, microbial zone gowthwas not observed, while in samples containing streptomycin and nanoparticles, microbial gowth zonewas created, and nanoparticles was effective than streptomycin. Regard to mentioned findings and films conditions on other tests, it seems that films containing chitosan and nisin had better conditions as a film, but nanoparticle and streptomycin based film had more capability as an antimicrobial biodegadable film.

Eggs are one of the common sources of infection transmission to humans and their contamination with germs such as Yerisina Entrocolitica may be followed by side-effects of them. The present study is conducted to identify Yersinia entrocolitica in eggs based on two methods of culture and PCR. Within a period between January 2015 to May 2016, 400 eggs were bought randomly from egg stores in Arak County and they were tested to identify Yersinia Entrocolitica based on bacteriology method. The species of this pathogen were separated and put to PCR test in order to determine Yersinia entrocolitica. In all,48 out of 400 sampled eggs, (12%) Yersinia entrocolitica was separated based on bacteriology method which in PCR test, 8 out of 48 samples which were reported positive in terms of serotype O3.

Probiotics are microorganisms that will be useful for host healthy, if sufficiently add to food products. Great part of probiotics belong to lactic bacterias. Treditionally, cold dairy product is superior way for production and cultivation of probiotics. Diluted yoghurt is one of the native drinkable in Iran that has long historical antecedent. Heracleum Persicum is usable as flavouring and also as pharmaceutical herb. In this investigation, Heracleum Persicumherb essence has extracted with distillation way by water and studied minimum inhibitory concentration (MIC) and Heracleum Persicumherb fatality with dilution method in agar medium on Plantarum Lactobacillus (PTCC 1058), in five concentration 0, 0.5, 1, 2, 3, 4, 5 in laboratory. Heracleum Persicumherb essence in three concentration 3, 2, and 1% accompanied by Plantarum Lactobacillus added to diluted yoghurt. Then evaluated essence effect on Plantarum Lactobacillus bacteria survival, acidity, pH changes, sensory properties. Finally, results assessed in three replication by SPSS. The results distinguished that probiotic bacteria decreased when storage time increased. Nevertheless, the number of Plantarum Lactobacillus significantly (PHeracleum Persicumherb essence concentration. Also, Heracleum Persicumherb essence caused increase pH and decrease acidity that this caution resulted in increase survive of Plantarum Lactobacillus. It should mention, this essence was no significant on flavour, odor and total acceptable.