جستجوی مقالات مرتبط با کلیدواژه « پونه کوهی » در نشریات گروه « صنایع غذایی »

In present study, the effect of different levels of oregano essential oil (0, 250 and 500 ppm) and gellan gum (0, 0.25, 0.5 and 0.75%) on the physicochemical, microbial and sensory properties of doogh during 60 days of storage in refrigerator conditions. The results showed that gellan gum and oregano essential oil had no significant effect (p<0.05) on the chemical properties of doogh including acidity, pH, fat and dry matter. Adding gellan gum to doogh increased the viscosity and stability of Doogh. Oregano essential oil significantly increased (p<0.05) DPPH radical inhibition and reduced oxidation. The minimum inhibitory concentration and the minimum bactericidal concentration of oregano essential oil on Escherichia coli are 1.6 and 3.12 mg/ml, respectively, and for Staphylococcus aureus, 0.4 and 0.80 mg/ml, respectively. was reported. In terms of sensory characteristics, the use of oregano essential oil and gellan gum did not have a significant effect (p<0.05) on the color of doogh, but the essential oil improved the flavor of doogh, gellan gum improved the mouth feeling. The doogh containing 0.5% gellan gum and 250 ppm of oregano essential oil had more acceptability and stability in terms of sensory properties and was free of contamination, which was recognized as the best treatment.

in recent years, the use of bioactive compounds in the formulation of meat and meat products has attracted the attention of experts.This research was conducted in two phases. In the first phase, aqueous, ethanolic and hydro-ethanolic extracts of Allium sativum controversum(Varcoaz) andMentha pulegium were extracted by soaking and the total phenols, flavonoids and antioxidant activity of the extracts were measured. The results of the first phase showed that the ethanolic extract of both plants had the highest amount of total phenol, flavonoids and antioxidant activity and as a result, this extract was selected for injection into sausage formulation at levels of 0.5, 1 and 1.5%. In the second phase, the treatments were kept at refrigerator temperature on1,15 and30 days, during which time a number of microbial tests were performed on them and a control sample (sausage without any extract). In terms of coliform count, no countable colony was observed on first day. During the 15th to 30th days, the control sample showed the highest number and the treatment containing 1.5% of Varcoaz extract showed the lowest number of coliforms. In terms of the number of Staphylococcus aureus, during the 15th to 30th days, the control sample had the highest number of this bacterium, while the treatment containing 0.5% ofAllium sativum controversum extract showed the lowest number. During the first 15 days, no countable number of molds and yeasts were observed in the studied treatments, but on 30th day, the treatment containing 1.5% of Varcoaz extract showed the lowest number of molds and yeasts and the control sample had the highest number of them.

The emergence of antibiotic resistance has a serious challenge to the control and treatment of pathogenic bacterial infections. Nanotechnology and the use of nanoparticles are some of the most effective approaches to overcome this topic. Silver nanoparticles have been studied as an antibacterial agent more than other nanoparticles by researchers. In this study, the antibacterial effect of silver nanoparticles synthesized by three methods including; bacterial, plant extract, and chemical procedure were compared. So, we synthesized silver nanoparticles using the supernatant of Bacillus spp. with Zarshouran gold mine source, oregano extract, and sodium borohydride chemical. Then, the minimum inhibitory concentrations (MIC) of silver nanoparticles against Escherichia coli, Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa were investigated. Comparison of the MIC results showed that the antibacterial effect of nanoparticles synthesized with Bacillus spp. was more than fivefold higher than the plant extract and chemical synthesis method. We showed that the minimum inhibitory concentration of nanoparticles synthesized with Bacillus spp., oregano extract, and sodium borohydride ranged from (1.4-5.6 μg / mL), (5.6-22.5 μg / mL), and (22.5-45 μg / mL), respectively.

Edible films, which in addition to creating beneficial effects by carrying antimicrobial compounds, antioxidants, etc., have biodegradable properties, have attracted the attention of many researchers. In this study, the gum obtained from the inner pod of bean with two concentrations of glycerol (40 and 60%) and three concentration of oregano essential (1, 2 and 3%) oil was used to produce biofilms. After studying the physicochemical and mechanical properties of the resulting films, the best treatment was combined with titanium oxide nanoparticles in two concentrations of 1 and 2% and its antimicrobial properties were also investigated. The results showed that increasing the essential oil raised the film thickness, while high concentrations of essential oil decreased the moisture content of the films. Although the addition of essential oil reduced the solubility of films compared with control sample, but in the treatments with essential oil, increasing the essential oil reduced the solubility of the film. Increasing the concentration of essential oil also increased turbidity and free radical DPPH activity. High concentrations of essential oil decreased the lightness of the films but increased the yellowing and redness compared to the control sample. Due to the interaction of the oil in the essential oil with the gum, the cohesion of the polymer network decreased and consequently, the tensile strength and the elongation factor at the break point decreased. Antimicrobial effect of films with 3% essential oil and 2% titanium oxide had the highest inhibitory area in the disk diffusion test with other samples on Staphylococcus Aureus, Escherichia coli, Salmonella Typhoid, Bacillus Cereus and pseudomonas Aeruginosa significantly (p<0.05)

Nowadays, due to some problems, such as allergic reactions and high fat content, the partial replacement of cow's milk with milk of other animals, such as goat's milk, is so crucial by proper techniques to improve the quality with the aim of yogurt production. The aim of this study was to evaluate the effect of Zataria multifliora and Mentha longifolia L extract on the qualitative characteristics of probiotic yogurt produced from the cow-goat milk in proportions 10: 90, 30: 70, 50: 50 and 0: 100. Sensory evaluation was performed on produced samples one day after production to selecting the best samples and then, the experiments were carried out on selected samples during 28 days. The results showed that, over time, acidity and syneresis values increased and pH value, viscosity and probiotic count decreased. The highest viscosity was related to the equal ratio of cow - goat milk and 0.05% of Zataria multifliora extract. The antioxidant activity (AA) trend was irregular but descending and extracts had a significant effect on AA. The treatment of cow-goat milk (10 : 90%) and 0.03% of Zataria multifliora extract had the highest probiotic count. The treatment of cow's milk (100%) containing the equal concentrations of two extract (0.02%), showed the highest color, taste, consistency and overall acceptance scores by panelist. As a conclusion, it can be concluded that in order to achieve the best quality of probiotic yogurt, various concentrations of extracts and optimal ratios of cow-goat milk should be used. .

The use of synthetic antioxidants has reduced due to its harmful effects on consumer health. The present study was conducted to evaluate the antioxidant properties of Mentha pulegium as a source of natural antioxidants. In order to prepare extracts of Mentha pulegium from a methanol solution, a ratio of 5: 1 was used. The levels of tocopherol and phenolic compounds of the extracts were measured by spectrophotometric methods. Finally, methanolic extract of Mentha pulegium at concentrations of 400 ppm and 800 ppm was added to canola oil, and after heating for 24 hours at 180°C, color index, conjugated dienes value, acid value and peroxide value were evaluated to comparison with the sample containing TBHQ. The results showed that extract at concentration of 800ppm has thermal stabilization efficiency comparable to TBHQ(p<0.05). Therefore, Mentha extracts can be recommended as a potent source of natural antioxidants for the stabilization of canola oil or other unsaturated vegetable oils.

The oxidation of fats and oils during food processing and storage not only causes loss of nutritional and digestive quality, but also produces compounds such as free radicals that lead to potentially biologically adverse and chemical reactions, Therefore, the use of antioxidants is essential to prevent the onset of corruption. Although many oils contain natural antioxidants such as flavonoids and tocopherols, due to insufficient efficacy of these compounds, they should be added to edible oils (Ibrahimzadeh et al. 2008). Synthetic antioxidants such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), and tertiary butylated hydroquinone (TBHQ) are commonly used to delay the oxidation spoilage of oils (Semnani et al. 2006). extraction and purification of rosemary extract and its extensive supply for nutrition and hygiene as a natural antioxidant (sunjae et al. 2011) or extract of iranian oregano extract and evaluation of antioxidant activity and competition with BHT synthetic antioxidant in sunflower oil there have been some of these efforts (kamkar et al. 2010). Other plant sources that have been studied in recent years for antioxidant compounds in their essential oils or extracts can be found in Laurus nobilis</em> (Inan et al., 2012), Citrus aurantium</em> (Saro et al. 2013), Pulicaria  gnaphalodes</em> (Kamkar et al. 2013), lavender (Tahanjad et al. 2010) and Malva sylvestris</em> (Tahanjad et al. 2012) were noted.In order to investigate the antioxidant potential of the active ingredients in aromatic plants, the present study evaluated the antioxidant properties of the essential oil of Oregano in comparison with the synthetic antioxidant of TBHQ in frying oil stability.

Oregano was collected from the area around Shooshtar in Khuzestan province in mid-autumn and after wash and rinse to remove dust, it was dried at laboratory (temperature 28 ° C and 44% relative humidity) and then 100 g of The dried plant was transferred to a Clevenger apparatus and extracted for 3 hours and then dehydrated with sodium sulfate and stored at 4 ° C. Compounds of extracted essential oil by injection of 0.5 μl Cyclohexane diluted essential oil to Agilent 6890A gas chromatograph containing HP-5 column (30 m length, 250 μm internal diameter and 0.25 μm constant phase thickness) attached to Agilent 59 mass spectrometer is identified. Total phenol content of the essential oil was determined by Folin-Ciocalteu method and its antioxidant activity by DPPH and ABTS tests. Antioxidant activity of oregano essential oil at three levels of 200, 500 and 1000 ppm and TBHQ synthetic antioxidant at 200 ppm in antioxidant-free frying oil (consisting of 60% soybean oil, 40% palm and 100 ppm citric acid) at 90 ° C on days 0, 1, 2, 3, 4, 5 and 6 were evaluated by measuring peroxide value and thiobarbituric acid test.

Based on the results, twenty-two compounds were identified by water distillation. It contained 95.3% of the essential oil. Of these, polygon (31.54%), cineol 1-8 (15.88%), menthofuran (11.8%) and cis iso-polygon (9.74%) constituted the major constituents of the plant essential oil. The results of this study were somewhat different from those of others. The differences in the type of essential compounds and their percentages in the essential oils can be attributed to differences in climatic and plant growth, harvest time, shelf life, method of extraction, and finally genetic variation of the plant. Each gram of oregano essential oil contained 7.5 mg phenolic compounds based on gallic acid on dry matter. There was a direct relationship between the essential oil concentration and its DPPH scavenging effect. The EC50 index of oregano essential oil was 1 mg / ml. Radical inhibitory power of oregano essential oil was compared with synthetic antioxidant TBHQ and the results showed that oregano essential oil at a concentration of 1 mg / ml had inhibitory power equivalent to 0.06 mg / ml of TBHQ antioxidant. Based on the results and comparison of EC50 essential oil with those investigated by other researchers, it is clear that the essential oil has good antioxidant activity and has good antioxidant activity compared to other antioxidant sources. There was a direct relationship between the essential oil concentration and ABTS radical scavenging ability. Evaluation of antioxidant activity of essential oil in fried oil for 6 days at 90 ° C in terms of peroxide and thiobarbituric acid values showed that Peroxide value was dependent on the concentration of treatments and decreased with increasing concentration of treatments and hence there was a significant difference (P<0.05). On the other hand, no significant difference was observed between the concentrations of 500 and 1000 ppm (P<0.05). In the first days of the test, concentrations of 500 and 1000 ppm of Oregano essential oil and TBHQ antioxidant reduced the same amount of peroxide but were weaker than TBHQ antioxidant on day 4 and reduced peroxide to a lesser extent. The concentration of 200 ppm essential oil from day 4 did not show any significant difference with control. Concentration of 500 ppm of Oregano Essential Oil during the Test with TBHQ Antioxidant Reduced Thiobarbituric Acid. The results of this study showed that Oregano essential oil has high potency in inhibiting DPPH and ABTS radicals and in terms of changes in peroxide and thiobarbituric acid during storage under oxidation conditions and the effect of essential oil concentrations in comparison with synthetic antioxidants. The results of this study indicated that oregano essential oil can be used as a replacement for synthetic antioxidants in oil and in addition to eliminating synthetic antioxidants, which can cause cancer by accumulating in tissues and organs, enhancing the thermal stability of the oil without causing undesirable changes.

Different concentrations of oregano essential oil showed antioxidant activity and decreased oxidation rate. Volatile compounds, although they play the most important organoleptic role in oils, have a negative effect on the sensory properties of the product during frying and over time, possibly due to oxidation and formation of substances. It produces a bad taste and smell. Also, because of its ability to react with oxidation-induced radicals, this essential oil can be used as a natural antioxidant in food products, especially fatty foods and prolong their shelf life. In addition, natural antioxidants are safe and beneficial to the consumer

Consumer demands have led to a renewed interest in using natural antimicrobial for food products. Biopreservatives such as essential oils and Probiotics have recently gained an increased attention to achieve an enhanced level of product safety and stability in food preservation industry. The study was designed to evaluate the antimicrobial effect of Mentha Longifolia L. essential oil in combination with Lactobacillus casei on Staphylococcus aurous in Iranian white cheese. The essential oil of this plant was obtained by steam distillation and analyzed by GC/MS. Effect of different concentrations of this essential oil and Lactobacillus casei on Staphylococcus aurous were determined by the growth culture on the selective media at different intervals of production, ripening and storage of Iranian white cheese. It was demonstrated that 0.03% and 0.015% of this essential oil had the highest inhibitory effect on the growth of Staphylococcus aurous when it was used in combination with Lactobacillus casei, and its reduction rate at the end of the storage period in experimental treatments were 1.89 and 2.32 Log more than the control group respectively. Furthermore, 0.015% of this essential oil combined with Lactobacillus casei has not only had the inhibitory effect on the growth Staphylococcus aureus but it also maintained concentration of the acceptable range. The synergistic effects between the above mentioned concentration levels of the essential oil and lactobacillus casei compared to the control and only essential oil was significant. Thus, the lower concentrations of essential oil can be used when it is combined with the probiotic to exert an inhibitory effect against Staphylococcus aureus.