Mitra Mansouri Bani; Vahid Samavati; Marzieh Bolandi
Abstract
Introduction: The Cholesterol in our diet is a risk factor for the prevalence of cardiovascular diseases. One of the effective ways to reduce the incidence of such diseases is to remove cholesterol, including animal fats, from our food sources. In this research, attempts were made to investigate the ...
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Introduction: The Cholesterol in our diet is a risk factor for the prevalence of cardiovascular diseases. One of the effective ways to reduce the incidence of such diseases is to remove cholesterol, including animal fats, from our food sources. In this research, attempts were made to investigate the effect of operational factors on reducing cholesterol in cream by beta-cyclodextrin using RSM and to examine its physicochemical properties. The variables in this study were beta-cyclodextrin concentration, mixing temperature and mixing time. Materials and Methods: The 3.5% fat raw milk was pasteurized at 72°C for 16 s, and then it was cooled to 55°C. The milk cream was separated by a separator and adjusted to 36% fat. Beta-cyclodextrin was added in 0.5, 1, 1.5% concentration in water bath at three levels of 10, 30, 50 ° C. It was mixed at three time intervals of 5, 15, 25, min. Cream containing beta-cyclodextrin was centrifuged to eliminate the complex formed in different periods and the beta-cyclodextrin and cholesterol complex was isolated. Beta-cyclodextrin of 99.2% purity was purchased from Sigma-Aldrich and all chemical agents from Merk, Germany. To measure cholesterol content in the preparation phase, hexane and ethanolic solution of potassium hydroxide (Merk) and the standard solution of cholesterol (Merk) were used. To determine the level of cholesterol in the samples, Lee et al. (1999) method was used after a few modifications. Firstly, cholesterol was extracted from the specimens and the cholesterol levels in the samples were determined with a chromatography apparatus equipped with flame ionization. The quantitative measurement of cholesterol was conducted by comparing the peak areas with a response from the internal standard. The experiments were designed, using the response surface method and the Box-Behnken Design (BBD), to achieve a high-efficiency process in reducing the highest cholesterol level and determining optimum conditions. The viscosity was determined using a Brookfield viscometer, and the over run and foam stability of the cholesterol cream samples were determined using a Graduated cylinder. Results and discussion: Due to the cavity in the central part of beta-cyclodextrin molecular arrangement, it can form a stable cholesterol-insoluble complex and help to isolate it from the product. The results showed that time, mixing temperature, and beta-cyclodextrin concentration all had a positive effect on reducing the level of cholesterol, and the effect of independent factors was almost the same, as the time factor had the highest effect, supported in Makoto et al. (1999). Concentration factor had the least effect on cholesterol reduction, contrary to studies by Aryafar et al. (2007) and Yen et al. (1995). Among the interactions of the investigated factors, the highest effect was due to the simultaneous effects of temperature and time (88.9%) and the least effect was due to the simultaneous effect of concentration and temperature (85.5%). Findings of this study showed that the use of beta-cyclodextrin resulted in a successful reduction of cholesterol from the product without affecting tissue properties, increasing viscosity and volume, or reducing stability of the foam. The absorption of cholesterol by beta-cyclosporine depends on its concentration. The mixing time and temperature also boosts the effect. After examining the effects of each independent variable, it can be concluded that all three investigated variables have an incremental effect on the level of cholesterol in the evaluated levels. Increasing mixing time has the highest effect on increasing cholesterol and increasing the concentration of beta-cyclodextrin has the lowest effect on cholesterol reduction. Investigating the interaction effects of variables also showed that the simultaneous effect of temperature and time with the proper concentration of beta-cyclodextrin could have a significant effect on cholesterol reduction. The response surface method and Box-Behnken Design as statistical optimization and modeling techniques enabled the researchers to predict the optimal conditions for maximal removal of cholesterol by beta-cyclodextrin at the decided levels. The optimal operating condition obtained by the model for 36% fat cream contains 42.1% beta-cyclodextrin concentration, 76.75 ° C temperature and 87.83 min of mixing time. The predicted cholesterol reduction in these conditions was 89.92%, which was very close to the experimental value obtained in predicted optimal conditions. It indicates the accuracy and predictive power of the intended model.
Hajar Shahsavar; Marzieh Bolandi; Homa Baghaei
Abstract
Introduction: Plant extracts have antimicrobial properties and can be substituted as chemical flavorings in food. Preservatives are compounds that are used to inhibit the growth or to eliminate harmful microorganisms to increase the shelf life of foods. Nowadays, the use of natural preservatives derived ...
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Introduction: Plant extracts have antimicrobial properties and can be substituted as chemical flavorings in food. Preservatives are compounds that are used to inhibit the growth or to eliminate harmful microorganisms to increase the shelf life of foods. Nowadays, the use of natural preservatives derived from medicinal plants is increasing due to their greater compatibility and the presence of volatile compounds (Celiktas et al., 2007). The antimicrobial properties, antioxidant and anticancer effects of these natural additives have been proven (Tajkarimi et al., 2010). In this study, the antimicrobial activity enhancement effect of the combination of hydroalcoholic extracts of basil, cinnamon and salvia on Escherichia coli, Staphylococcus aureus and Saccharomyces cerevisiae yeast in Iranian yoghurt drink (doogh) was investigated for 4 weeks at ambient temperature. Materials and Methods: The milk was boiled in hygienic conditions at 95 ° C for 5 min. After cooling to 45 ° C, they were inoculated. The aerial parts of the studied plants were milled and powdered. Cinnamon, basil and salvia extracts were then soaked. The food strains of Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 700728 and Saccharomyces cerevisiae PTCC 5193 were prepared as lyophilized ampoules. The microdilution broth method was used to determine the minimum inhibitory concentration. The minimum bactericidal concentration (MBC) was determined in accordance with the minimum inhibitory concentration (MIC) results. To determine the antimicrobial effect of the extracts on the yoghurt drink, 9 ml of the prepared yoghurt drink was poured into each test tube. Then 1 cc of each extract and 1 cc of microbial suspension (1.5 × 108 CFU / ml) were added. One tube was considered as positive control (bacteria + yoghurt drink), one negative control tube (extract + yoghurt drink) and one control tube (yoghurt drink only) and the tubes were placed at ambient temperature. Then, on day 7, 14, 21 and 30 during storage, 20 µl of each tube, were cultured on Muller Hinton agar medium and the same amount of yeast was cultured on blood agar medium. After incubation for 24 h at 37 ° C, the colonies were counted. The interaction of antimicrobial activity of the combination of basil, cinnamon and sage extracts was evaluated on the basis of differential inhibitory concentration index (FIC). Results and discussion: The results showed that the minimum inhibitory concentration of the combined basil, cinnamon and sage extracts against Staphylococcus aureus and Saccharomyces cerevisiae and Escherichia coli were 0.4, 0.4 and 3.12 mg / ml, respectively. Also, Staphylococcus aureus was more susceptible to the extracts, which were used alone, and was inhibited by a lower concentration of used extract (Ahmadi et al., 2018). However, due to the maximum minimum inhibitory concentration (MIC), Escherichia coli was less sensitive to the extracts which was used alone. The combined usage of all three extracts significantly reduced the maximum minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), indicating that their antimicrobial activity was more effective against the studied microorganisms than each of the extracts which was used alone. The results of this study showed that synergistic effect against Staphylococcus aureus and Saccharomyces cerevisiae was more effective with the combination of the aforementioned extracts (p <0.05). The results of the Escherichia coli population counting during storage indicated that most of the extracts had a good effect on preventing the growth of Escherichia coli in the doogh environment compared to the control sample (p <0.05). Addition of the extract significantly prevented pH reduction over time (p <0.05), so that the control sample had the highest and the sample containing all three extracts showed the lowest pH changes over time (p <0.05). Therefore, it can be concluded that acid production by Lactobacillus bacteria in samples containing extract during storage period was higher than control. The results of this study were in agreement with the results of Mortazavian et al., (2007) and Voosogh et al., (2009). The acidity of the doogh samples increased significantly over time (P<0.05), while the addition of the extract significantly prevented the acidity increase over time (P<0.05). Sensory properties are the main factors of acceptance and satisfaction of many products. In this study, the mean viewpoint of doogh samples containing the combination of the three above mentioned extracts in terms of taste, odor, color and general acceptance are acceptable. Additionally, it was found that about 90% of participants were willing to use it. Although studies of the overlapping or synergistic effects of medicinal plant extracts in real food environments are not extensive, their results have shown that, the addition of different medicinal plants compounds can increase antibacterial effects. Therefore, the simultaneous use of these extracts can be used in effective control of food pathogens as a complementary method. The results of this study were in agreement with the results of Karimi (2007).
Ashraf Nazarian; Seyed Ali Mortazavi; Majid Arab Ameri; Marzieh Bolandi; Mohammad Mahdi Karimkhani
Abstract
Recently great afford have focused on the production of food and beverages which are rich in phenolic and antioxidant components. The epidemiology investigations have proved that the regular Composition of food and beverages are richer in phenolic and antioxidant components can strongly decrease the ...
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Recently great afford have focused on the production of food and beverages which are rich in phenolic and antioxidant components. The epidemiology investigations have proved that the regular Composition of food and beverages are richer in phenolic and antioxidant components can strongly decrease the cardiovascular disease. This was done after the preparation of components such as soymilk mixed with sour cherry and barberries juice. In this research, the DPPH free radical method bas been used in order to analyses the antioxidant activity, Folin-Ciocalteau and pH differential method were to estimate the amounts of phenolic compounds and antioxidant and anthocyanin . Also the amount of vitamin c was estimated by standard method which is used for fruit juice . The data's were analyzed by SAS software . The maximum scavenging capacity of radical DPPH wsa seen in sample (20 %soymilk and 80% juice ) with the average of 41. 88 %SC (ppm) ,85. 5 mg/100ml of anthocyanin content,10. 12 mgGAE /gr dry extract phenolic contents and 4. 192 mg/100ml of vitamin c were reported which showed reduction in order samples . corrolational researches shows appositive and significant relation ship between the phenolic contents and anthocyanin and vitamin c of compound and their ability in neutralization of DPPH radical.
