Food Biotechnology
َAlireza Hemmati; Ali Ganjloo; Kambiz Varmira; Mandana Bimakr
Abstract
Introduction It is believed that edible oils and fats with high levels of unsaturated fatty acids are susceptible to oxidation. Soybean oil as one of the four important edible oils has high content of polyunsaturated fatty acids and so prone to oxidation. Generally, lipid oxidation leads to deterioration ...
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Introduction It is believed that edible oils and fats with high levels of unsaturated fatty acids are susceptible to oxidation. Soybean oil as one of the four important edible oils has high content of polyunsaturated fatty acids and so prone to oxidation. Generally, lipid oxidation leads to deterioration of nutritional quality and organoleptic properties of edible oils and fats as well as accelerate the development or progression of cancer, mutagenesis, carcinogenesis, aging and cardiovascular diseases through the formation of free radicals. Therefore, edible oils and fats fortification with antioxidant compounds in order to protect them against oxidation is essential. In recent years, numerous studies were carried out on exploration of natural and safe antioxidant compounds due to the consumers concerns about potential health risk of synthetic antioxidants, such as butylatedhydroxyanisole (BHA), butylatedhydroxytolene (BHT), tert-butylhydroquinone (TBHQ) and propylgallate (PG). In this regard, TBHQ as the most powerful synthetic antioxidant is prohibited as food additive in Japan, Canada and Europe. Ferulago angulata Boiss which called chavir or chavil belongs to the family of Apiacea consisting of 35–40 species that 8 species grow in Iran. It was reported that Ferulago species are used in folk medicine for their tonic, digestive, sedative, aphrodisiac properties from ancient times. Therefore, in the current study, the oxidation development of soybean oil enriched with F. angulata essential oil (EO) during accelerated storage was investigated. Materials and Methods EO from freeze dried aerial parts of F. angulata was extracted through hydrodistillation using Clevenger type apparatus. Gas chromatography-mass spectrometry (GC-MS) was used to identify main components of the EO. Total phenolic and flavonoid content of the EO were assessed using Folin–Ciocalteu and aluminium chloride colorimetry methods, respectively. Antioxidant activity of EO was measured through 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) and reducing power (RP) tests. Then, the EO of F. angulata at three concentrations, i.e. 200 ppm (SO-200), 400 ppm (SO-400), and SO-Mixture (100 ppm TBHQ + 100 ppm EO) were added to soybean oil. The synthetic antioxidant of TBHQ at the concentration of 200 ppm was added as control. The effect of EO from freeze dried aerial parts of F. angulata on oxidative stability of soybean oil stored under accelerated conditions at 65 ºC for 24 days was evaluated through acidity, peroxide (PV), p-anisidine (p-An) and TOTOX values. Results and Discussion Extraction yield, total phenolic and flavonoid contents of EO of F. angulata were 2.5% v/w, 188 mg GAE/g and 70.90 mg QE/g respectively. Furthermore, DPPH free radical scavenging activity and RP were 55.45-13.21% and 3.61-2.72 in the concentration range of 1.6-4.6 mg/ml of EO, respectively. Based on GC-MS analysis, the EO contains 41 natural compounds, representing 96.97% of the total EO. F. angulata EO could effectively reduce the acidity, PV and p-An values. For control sample, the maximum values of acidity, PV peroxide, p-An and TOTOX were 1.52 mg KOH/g, 10.60 meq O2/kg, 12.48 and 33.68 respectively after 24 days under accelerated conditions. While these values were 0.085 mg KOH/g, 4.5 meq O2/kg, 9.16 and 18.16 respectively for the soybean oil containing the lowest concentration of EO of F. angulata. Conclusion The results confirmed the instability of soybean oil during storage as well as the ability of EO from F. angulata for soybean oil protection against oxidation. As a result, EO from aerial parts of F. angulata could be suggested as a natural and effective antioxidant to be used instead of TBHQ as a synthetic antioxidant for soybean oil stabilization.
Bahareh Khaligh; Maryam Gharachorloo; Peymaneh Ghasemi Afshar
Abstract
Introduction: The impurities of the oil and its pigments are basically removed from the oil by physical adsorption using an adsorbent during the bleaching process. The bleaching process involves the removal of pigments, impurities, metals and oxidation products. Removal of these substances is essential ...
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Introduction: The impurities of the oil and its pigments are basically removed from the oil by physical adsorption using an adsorbent during the bleaching process. The bleaching process involves the removal of pigments, impurities, metals and oxidation products. Removal of these substances is essential in oil refining because it improves the stability, appearance and sensory quality of the oil. Activated bleaching earth is the most commonly used adsorbent for purifying and improving the color of fats and oils. The bleaching process of edible oils is important for producing light colored oils with acceptable quality. The aim of this study was to evaluate the physical and chemical properties of soybean oil bleached with bleaching earth containing increased amounts of aluminum and magnesium oxides. Material and Methods: Bleaching earth was purchased from Kanisaz Jam Company. Degummed and neutralized soybean oil was obtained from Behshahr Vegetable Oil Company. Different amounts of aluminum oxide and magnesium oxide were added to commercial bleaching earth. Activation of the adsorbents was performed with hydrochloric acid and oil bleached at 110°C for 30 min under vacuum by adding 2% of adsorbent containing different percentages of silica, aluminum and magnesium oxides. A series of physical and chemical tests such as peroxide value, acid value, chlorophyll content, carotenoid content, yellow and red colors and amounts of copper and iron were then carried out on the neutralized and bleached oils according to the standard methods. All the experiments and/or measurements were carried out in triplicate. Data were statistically analyzed using the Statistical Analysis System software package on replicated test data. Analysis of variance was performed by application of an ANOVA procedure. Significant differences between the means were determined using the Duncan multiple range test. Result and Discussion: The results of this study showed that the examined adsorbents reduced the peroxide value to 98.9-96.3%. Application of the adsorbents containing 95% commercial bleaching earth - 5% aluminum oxide and 95% commercial bleaching earth - 5% acidic aluminum oxide reduced the acid value by 33.33% and 26.66%, respectively. The amount of chlorophyll in the control sample was 7.58 mg Pheophytin A/kg oil, which reduced 65.66% by using adsorbent containing 90% commercial bleaching earth and 10% magnesium oxide and reached to 1.90 mg Pheophytin A/kg. The amount of carotenoids in the control sample was 7.88 mg/kg. Using the adsorbent containing 90% commercial bleaching earth and 10% magnesium oxide decreased carotenoids up to 93.40%. Adsorbents containing 95% commercial bleaching earth and 5% aluminum oxide, 95% commercial bleaching earth and 5% magnesium oxide, 95% commercial bleaching earth and 5% acidic magnesium oxide and commercial bleaching earth had the same effect on red color reduction. Yellow color in the oil samples treated with commercial bleaching earth, adsorbent consisting of 90% commercial bleaching earth - 10% aluminum oxide, and adsorbent containing 95% commercial bleaching earth - 5% magnesium oxide was reduced and reached to 38, 50 and 50 Lovibond, respectively as compared to the control sample with yellow color of 70.00 Lovibond. Copper and iron decreased 100% by using adsorbents containing 50% commercial bleaching earth and 50% aluminum oxide or 50% commercial bleaching earth and 50% magnesium oxide.According to our findings, the addition of aluminum and magnesium oxides to commercial bleaching earth was effective in reduction of peroxide value, acid value, chlorophyll, carotenoid, red and yellow color, copper and iron. Also, the results showed that the best adsorbent contain about 50% aluminum and magnesium oxides. Aluminum and magnesium oxides can improve the performance of bleaching earths.
Forouzan Jalali-zand; Mohammad Goli
Abstract
Introduction: Microencapsulation is represented as a technology of packaging solids, liquids, or gaseous materials in miniature sealed capsules that can release their contents at controlled speeds under specific conditions. The packaged materials can be pure materials or a mix, which are also called ...
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Introduction: Microencapsulation is represented as a technology of packaging solids, liquids, or gaseous materials in miniature sealed capsules that can release their contents at controlled speeds under specific conditions. The packaged materials can be pure materials or a mix, which are also called coated material, core material, actives, internal phase (Fang & Bhandari, 2010). Selenium is a micronutrient essential element for human health, which is toxic in high concentrations. Selenium is a component of selenoproteins that plays an enzymatic and structural roles in human biochemistry. Selenium is known as an antioxidant and catalyzer for active thyroid hormone production. The aim of this study was to optimize the microencapsulation of sodium selenite (100-900 mg per 20 mL final spray solution) using a combination of Arabic gum (25-29% per 20 mL final spray solution) and Persian gum (1-5% per 20 mL final spray solution) as capsule wall applying modified solvent evaporation method to produce microcapsules with the highest encapsulation efficiency (EE) and the smallest possible particle size using the response surface method (RSM) with central composite design (α = 2 with 6 central points and 2 repetition in axial and factorial points). Materials and Methods: In this research, production of encapsulated sodium selenite at different concentration (100, 300, 500, 700 and 900 mg/20 cc) with Arabic gum (25%, 26%, 27%, 28% and 29%) and Analogous Farsi gum (5%, 4%, 3%, 2% and 1%) as wall materials by solvent evaporation method was studied. The optimization of microcapsules based on the highest encapsulation efficiency and smallest microcapsules size was studied using RSM. Based on the mentioned parameters, 2 optimum conditions were chosen. The first one was a condition where the samples produced with 135 mg sodium selenite in 20 ml sprayed solution, 27% and 3% Arabic and Farsi gum, respectively. In this condition the encapsulation efficiency was 79.63% whereas the microcapsules size was 49.98 µm. The second condition was followed by producing samples with 109 mg sodium selenite in 20 ml sprayed solution, 28% and 2% Arabic and Farsi gum with result of 95.10% encapsulation efficiency and the size of 46.71 µm. Finally 390 ppm capsules of the first condition and 480 ppm capsules of second condition (equal to 8.6 ppm sodium selenite salt), synthesized BHA (200 ppm) and sodium selenite salt (8.6 ppm) were added to a free anti-oxidant soybean oil and were kept at 55°C at 0, 23 and 46 days which was equal with 20°C at 0, 180 and 360 days. In this condition, peroxide value, acidity, Thiobarbituric acid, Anisidine value, Totox value and anti-oxidant activity of free anti-oxidant soybean oil were evaluated using SPSS software. Results & Discussion: The results achieved by RSM showed that sodium selenite concentration had reverse relation on encapsulation efficiency whereas there was direct relation with Arabic and Farsi gum concentration. Also the size of microcapsules with had direct relation on sodium selenite concentration whereas Arabic and Farsi gum concentration had reverse relation. The result of SPSS analyses showed that with presence of the encapsulated sodium selenite anti-oxidant and synthesized BHA anti-oxidant in soybean oil, peroxide value, acidity, Thiobarbituric acid, Anisidine value, Totox value decreased whereas anti-oxidant activity of soybean oil increased. Based on anti-oxidant characteristics in soybean oil, recommended treatments in this research are: condition 2 ˃ condition 1 ≥ BHA ˃ sodium selenite salt ˃ control sample without anti-oxidant. The results of this study recommend the incorporation of encapsulated sodium selenite (condition 1 and 2) for increasing the shelf life of soybean oil as an alternative to synthesized BHA.
Adeleh Mohammadi; Saeedeh Arabshahi- Delouee
Abstract
Introduction:Frankincense is a natural oleo-gum-resin which is obtained through slits made in the trunks of trees of the genus Boswellia (Family Burseraceae). The genus Boswellia is approximately represented by 43 different trees and shrubs distributed mostly in the India, Arabian peninsula, and east ...
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Introduction:Frankincense is a natural oleo-gum-resin which is obtained through slits made in the trunks of trees of the genus Boswellia (Family Burseraceae). The genus Boswellia is approximately represented by 43 different trees and shrubs distributed mostly in the India, Arabian peninsula, and east africa (mothana et al.2011). Trees from the genus Boswellia (Burseraceae) are traditionally used as a medicine, a fumigant, in various cosmetic formulations and in aromatherapy in several countries around the world.Frankincense therapeutic effect significantly depends on the amount of oleoresin. These effects include anti-inflammatory, hepatoprotective, anticancerous, anti-HIV, anti-microbial, antifungal, anti-ulcerous, gastroprotective, hypoglycemic andantihyperlipidemic properties (Aman et al. 2009; Al-Harrasi and Al-Saidi, 2008; Khadem et al. 2009 and Shah et al.2009).Lipids are susceptible to oxidation on storage and frying processes. Characteristic changes associated with oxidative deterioration include development of unpleasant tastes and odors as well as changes in color, specific gravity, viscosity and solubility.Lipid peroxidation is one of the major agents of deterioration for vegetable oils, fats and other food systems (Iqbal and Bhanger, 2007). During oxidation hydroperoxides are formed which again break down to form products like alcohols, aldehydes, ketones and hydrocarbons, which possesses offensive off flavors (Grace Roy et al.2010).In order to inhibit oxidation, synthetic antioxidants, such as BHA (Butylated hydroxyanisole), BHT (Butylated hydroxyanisole) and TBHQ Ter-butyl hydroquinone have been added to foods but there is concern about the use of these compounds due to their reported adverse effects on health. This has led to an increasing trend in the search and replace of these synthetic antioxidants with natural ones such as phenolic compounds (Mariod et al. 2006).Antioxidants affect the process of lipid oxidation at different stages due to differences in their mode of action. Because of the complexity of the oxidation process itself,the diversity of the substrates and the active species involved, the application of different test methods is necessary in the evaluation of antioxidants. The aim ofthisstudy was to evaluatethe antioxidantproperties of various solvent extractsand essential oil offrankincense(Boswellia serrata)and evaluation ofitsantioxidant activityinsoybeanoil.Materials and methods: In this study, the dried powder of B.serrata (25g) was extracted overnight in 250 ml each of methanol, ethanol and acetone respectively, in a mechanical shakerat room temperature and each extract was filtered with Whatman No. 1 filter paper. The filtrates obtained from methanol, ethanol and acetone extractions were evaporated at 40 °C in a rotary evaporator. The content of phenolic compounds was measured by Folin–Ciocalteu, Briefly 20 µl of extract solution were mixed with 1.16 ml distilled water and 100 µl of Folin–Ciocalteu reagent, followed by addition of 300 µl of Na2CO3 solution (20%) after 8 minutes. Subsequently, the mixture was incubated at oven at 40 °C for 30 minutes and its absorbance was measured at 760 nm.The ability of extracts to scavenge DPPH radicals was determined according to the method of Blois (1958). Briefly, 1 ml of a 0.1 mM methanolic solution of DPPH was mixed with 3 ml of extract solution in methanol (containing 100–1000 μg/ml). The mixture was then vortexed and left for 30 min at room temperature in the dark. The absorbance was measured at 517 nm. The percentageof the DPPH radical scavenging was calculated using the equation given below:% inhibition of DPPH radical= ( Abr - Aar ) / Aar×100where Abr is the absorbance before reaction and Aar is theabsorbance after reaction has taken place. The molecule 1, 1-diphenyl-2-picrylhydrazyl (a,a-diphenyl-bpicrylhydrazyl DPPH) is characterized as a stable free radical by virtue of the delocalisation of the spare electron over the molecule as a whole, so that the molecule does not dimerize, as would be the case with most other free radicals (Nur Alam et al., 2013).Next, oxidative stabilityand antioxidant activity of methanol extract concentrations (200, 500, 800, 1000 ppm) with the synthetic antioxidant TBHQ (100 ppm) were evaluated in soybean oil without antioxidants (63 ˚C, 12 days).Results and discussion: The extract significantly (p0.05) suppressed the formation of peroxides and thiobarbituric acid-reactive substances (TBARS) during accelerated oxidation, even at a level of 200 ppm. Based on the obtained results, the methanolic extract at 1000 ppm had the highest antioxidant activity among other extracts and inhibits the peroxide value and the index of thiobarbituric acid, but it coulden't compete with the synthetic antioxidant TBHQ. Results showed that, Boswellia Serrata was found as a potential source of natural antioxidants due to its marked antioxidant activity.