Sanaz Fallh-Taftizadeh; Gholamreza Abdi; Fatemeh Zendeboodi; Mahdi Mohammadi
Abstract
Introduction: Virgin olive oil has high oxidative stability due to its special compounds, including large amounts of monounsaturated fatty acids (MUFAs) and a wide range of natural antioxidants. However, virgin olive oil is easily oxidized due to the presence of polyunsaturated fatty acids (PUFAs), ...
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Introduction: Virgin olive oil has high oxidative stability due to its special compounds, including large amounts of monounsaturated fatty acids (MUFAs) and a wide range of natural antioxidants. However, virgin olive oil is easily oxidized due to the presence of polyunsaturated fatty acids (PUFAs), mainly linoleic and linolenic acids. Lipid oxidation is the main cause of poor food quality; for this reason, the use of antioxidants is essential to prevent the onset and progression of oxidative damage and increase the shelf life of oils and fats. Because lipid oxidation occurs following a complex set of processes and no antioxidant alone can stop all the oxidation steps and keep oxygen away, a mixture of antioxidants can be used to create a synergistic effect. Spirulina is a dry biomass of Artrhrospira platensis cyanobacteria. Flavonoids, β-carotene, vitamin A and α- -tocopherol in spirulina are largely involved in the high antioxidant activity of this microalgae. The Moringa oleifera plant belongs to the Moringaceae family, the genus Moringa and the species Oleifera. This plant is considered as a high-potency natural antioxidant because it is rich in tocopherols, carotenoids, vitamin C, flavonoids and phenolic compounds. Therefore, the aim of this study was to investigate the synergistic and symbiotic effect of spirulina and M. oleifera extracts as natural antioxidants to increase the oxidation stability and shelf life of virgin olive oil. Materials and Methods: To prepare the extracts of s. platensis and M. oleifera plant, both plants were dried in the shade at 30°C for 24 hours in the presence of air, then ground into a powder. Then, 5 g of s. platensis and M. oleifera powders were extracted with two solvent of ethanol (96%) and methanol. Antioxidant activity was evaluated by measuring the effect of free radical scavenging of ethanolic extracts of Algae Spirulina and Acacia on the synthetic radical DPPH. Determination of total phenol and flavonoid content of all extracts was performed using Folin-Ciocalteu reagent and aluminum chloride colorimetric method, respectively. Polyphenolic compounds of the extracts were identified by HPLC. Extracts were added separately (1000 ppm each) and in combination (500 ppm each) to 100g of virgin olive oil and a sample containing the synthetic antioxidant TBHQ and a sample of virgin olive oil were considered as control. Peroxide index, refractive index and color evaluation (L*, a*, b*) of virgin olive oil samples were measured. Statistical analysis was performed using SPSS software version 19 and the results were expressed as mean ± standard deviation. Results and Discussion: Based on the results obtained from ethanolic and methanolic s. platensis extracts, the highest amount of total phenol in ethanolic extract was equal to 67.19±4.5 mg GA/g and the highest amount of flavonoids in methanolic extract was equal to 12/1±40/267 mg QU/g. In the study of the content of total phenol and flavonoids in ethanolic and methanolic extracts of M. oleifera plant, there was the highest levels of total phenols and flavonoids in ethanolic extracts of this plant, respectively, 43.43±0.71 mg GA/g and 23.78±1.57 mg QU/g. The results showed that the active compounds in the extracts of S. platensis and M. oleifera are polyphenolic compounds of rosmarinic acid, catechin, quercetin, vanillin, hesperidin, hesperetin. Changes in peroxide value from the time of production and addition of the extract for 8 hours at 2 hour intervals were investigated. According to the results, the lowest amount of peroxide value (0.38±0.005 meq O2/kg) was related to the sample containing M. oleifera extract at the third storage time. The highest amount of peroxide value was observed in the control and the sample containing TBHQ in the range of 15 meq O2/kg. Generally, Changes in peroxide value were reduced significantly in the 3 samples containing the extract compared to the control sample and the sample containing TBHQ (p<0.05). The presence of extracts in virgin olive oil reduced the parameters of L*a*b*, but the sample containing S. platensis extract was no significant difference from the control sample (p >0.05). According to the results of peroxide index of samples containing extracts, it can be stated that by recognizing the antioxidant effects of S. platensis and M. oleifera extract, they can be used for industrial use and replacement with synthetic antioxidants.
Negin Zangeneh; Hassan Barzegar; Behrooz Alizadeh Behbahani; Mohammad Amin Mehrnia
Abstract
Introduction: Spirulina platensis belongs to the Division of Cyanobacteria and the family of Oscillatoriaceae. It is autotroph and photo-synthesizer and can be reproduced through double cell division. Spirulina platensis is a filamentous blue-green multi-cellular microalgae naturally occurring in the ...
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Introduction: Spirulina platensis belongs to the Division of Cyanobacteria and the family of Oscillatoriaceae. It is autotroph and photo-synthesizer and can be reproduced through double cell division. Spirulina platensis is a filamentous blue-green multi-cellular microalgae naturally occurring in the tropical and alkaline lakes of America, Mexico, Asia and central Africa. It contains unique and extraordinary nutrients which can be used in the production of functional foods. Among bakery and flour products, cake has a relatively high diversity and long shelf-life and is famous among a variety of people, especially children. Since the knowledge associated with the enrichment of sponge cake, as a popular product among different communities (in particular, children) is limited, the aim of the present research is to produce a sponge cake enriched with spirulina platensis, and to examine its nutritional, physicochemical and sensory properties. Materials and methods: In this research, the effect of Spirulina platensis at four levels (0, 0.5, 1 and 1.5%) was investigated on the nutritional properties (protein, fat, iron, zinc and copper contents), physicochemical properties (moisture content, pH, total phenol content, antioxidant potential, textural properties and color indices) and sensory attributes (odor, color, texture, flavor and taste, chewiness and total acceptance) of the sponge cake samples prepared with wheat flour. Results and discussion: Results showed that algae powder was rich in protein (56.33%) and iron (13.18 ppm). The addition of Spirulina platensis to the sponge cake caused reduction in its moisture content during storage (days 1, 5 and 10). The results also revealed that the different levels of algae addition brought about significant differences in the moisture content of the samples (p<0.05). The results also indicated that the protein, fat and mineral contents as well as other nutritional properties of the sponge cake increased as the algae content was elevated. The total phenol content of the cake samples was also raised with an increase in the algae powder level, compared with the control. This could be attributed to the large amounts of phytochemical and biological active substances such as flavonoids, sterols and other phenolic compounds. The results demonstrated that the porosity values of the control and the sample containing 1.5% of the algae were not significantly (p<0.05) different. The percentage of porosity was equal to 24.94, 37.99, 33.39 and 27.81 in the control and the samples containing 0.5, 1 and 1.5% of Spirulina platensis. Overall, the sample with 0.5% of the algae and the control had the highest and lowest porosity percentage respectively. As the algae level rose, the textural parameters (hardness, cohesiveness and gumminess) of the sponge cake increased on days 1, 5 and 10 of the storage period. The colorimetry results showed that the effect of Spirulina platensis was significant (p<0.05) on color parameters (L*, a* and b*). Sensory evaluation revealed that the sponge cake with 0.5% of the microalgae was the most acceptable among the samples. The green color of the cake crumb was attractive to the panelists and a comparison between the total sensory scores indicated that the incorporation of Spirulina platensis into the sponge cake was desirable from the panelists` points of view. The results of this study demonstrated that the addition of Spirulina platensis to sponge cake for the enrichment of this product, caused an increase in its protein and mineral contents, antioxidant potential, in addition to other functional ingredients naturally occurring in this algae. The results revealed that different levels of this algae (0.5, 1, and 1.5%) did not significantly affect the cake texture, however, had a significant impact on its color. Incorporation of Spirulina platensis into sponge cake reduced its L*, a* and b*, which was highly noticed by the panelists. Therefore, it can be declared that enrichment of sponge cake, as a popular product among different people of societies, particularly children, is a desirable and easy way of transferring the useful and valuable compounds of this algae to human.
Esmail Khazaei; Fakhri Shahidi; Seyed Ali Mortazavi; Mohebbat Mohebbi
Abstract
Introduction: Kiwifruit (Actinidia sp.) has many appealing properties for consumers such as flavor, color, and nutritional content, especially vitamin C. Kiwi seems to be used as one of the major ingredients within the formulation of this category of foods.Microalgae are nutritional and innovative natural ...
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Introduction: Kiwifruit (Actinidia sp.) has many appealing properties for consumers such as flavor, color, and nutritional content, especially vitamin C. Kiwi seems to be used as one of the major ingredients within the formulation of this category of foods.Microalgae are nutritional and innovative natural sources that can be used in the development of novel foods. Among the known species of algae, Chlorella vulgaris and Spirulinaplatensis are common edible microalgae that have no side effects on health of human. The amino acid, carbohydrate, and fatty acid profiles of these microalgae are very similar to those of other food materials. Spirulina is a multicellular filamentous blue-green microalga, which was introduced as generally recognized as safe (GRAS) after being approved by food and drug administration (FDA). Spirulina can also be incorporated into common food preparations such as pastas, biscuit, bread, snack,pastille, candy, yoghurt, soft drink, causing health-promotion that are associated with microalgae biomass.The aim of this study was to investigate the possibility of producing new product based on kiwifruit and its enrichment with Spirulinaplatensis microalgae so that this product could replace common snacks, especially the pastilles containing synthetic colors and flavors, which have increasingly been used day by day despite having a low nutritional value and causing a variety of side effects. The role of pHysicochemical and sensory properties is very important in producing new products which can help producers design the products suitably. Therefore, some of the pHysicochemical properties of the kiwi base pastille were examined in this study, as well as the formulation and enrichment of it with Spirulinaplatensis. Material and methods: The ingredients of the formulations consist of 65% w/w kiwifruit puree, 30% w/w sweeteners (sugar, powdered glucose, invert syrup and sorbitol), 0.25% w/w high methoxyl pectin, 0.5% Agar, 0.5% Guar and Spirulinaplatensis(0, 0.25, 0.5, 1 and 2% w/w) as well.In order to produce fruit pastille based on kiwifruit puree, the kiwifruits were fist washed up, peeled and cut into pieces. Then the pieces were grinded. The prepared puree was mixed with Spirulinaplatensis, hydrocolloids and sweeteners at 70°C with specific ratios. Agar was dissolved in distilled water at 90°C and added to the concerned mixture. Finally, after moderating pH to 3.4 by adding 40 M citric acid and controlling the Brix degree in constant Brix of 45, the mixture was prepared. The mixture was then poured into stainless steel mesh molds with cavity dimensions of 1.2 cm × 2 cm × 2 cm and the molds were kept at 4°C for 2 hours to form the gel. Then the obtained gel was taken out of the mold cavities and the samples were dried at 70°Cfor 6 hours in a hot air drier with 1.5 m/s airflow rate. Then the regarded tests were performed on the dehydrated samples. To measure pH, pH meter (Hana, Portugal) was used. The measurement of mixture Brix was performed by an optical refract meter (Carlze, Germany). The drying process of the samples was conducted in a hot air drier (Soroush Medicine Co. Iran).Moisture, protein, fiber, lipid, ash, vitamin C, calcium and iron elements were measured according to the Iran national standard.Texture profile analyzer (QTS25 CNS Farnell England) equipped with a software was used to determine the textural properties of the samples. Samples were compressed and decompressed in two reciprocating cycles by a round plate cylindrical probe with 3.5 cm diameter, 1 mm/s probe speed and 5 g force to 30% initial height.Histological properties obtained from force-deformation curve are as follows: Hardness, Cohesiveness, Elasticity, Adhesiveness and Chewiness.Sensory test was performed with the judgment of 10 trained panelists. In order to evaluate the samples. A 9-point Hedonic method (1: very undesirable - 9: very desirable) was used. 5 sensory attributes (color, texture, flavor, odor and overall acceptance) were evaluated.SPSS software was used for the statistical analysis of the parameters. Mean of the replicates were compared via the multi-range Duncan`s test at 95% confidence level.In order to pHotograpHy with Scanning electron microscope, initial preparation should perform on all of samples.The obtained sampleswas removed from the templates and were sectioned on a scale of 2×1×1mm. samples were dehydrated in ethanol solution and then dried in a critical point. Then samples with 30 nm of gold/palladium coated and were tested using SEM (model LEQ1450VP) in the maximum voltage of 15 kv. At least four images with magnification of 500, 1000, 2000 and 5000 were prepared in several different areas of the samples.Results and discussion: The obtained results indicated that the effect of Spirulinawas significant on the moisture content and increasing Spirulinaconcentration led to increased moisture content of the product.The results of texture profile analysis indicated that the hardness and chewness was increased, but the cohesivness of samples was decreased when the amount of Spirulina is increased. The amount of protein, vitamin C, total ash, iron and calcium was increased by increasing the amount of Spirulina. SEM microscopic results showed that adding up Spirulina is led to the reduction of the uniformity of sample’s structure and then the gel matrix will be created with a larger pore. Results of sensory analysis indicate that samples containing 0.25% Spirulina have sensory characteristics (color, aroma, flavor and overall acceptability) than other samples.
Seyed Amir Tavakoli Lahijani; Fakhri Shahidi; Mehdi Varidi; Mohebbat Mohebbi
Abstract
Spirulina platensis is a blue-green microalga with unique nutrient content and several therapeutic aspects which has been used for fortification of different foods. In this study, the effect of Spirulina platensis powder in different levels (0, 0.5, 1 and 2 percent), added in two stages (before pasteurization ...
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Spirulina platensis is a blue-green microalga with unique nutrient content and several therapeutic aspects which has been used for fortification of different foods. In this study, the effect of Spirulina platensis powder in different levels (0, 0.5, 1 and 2 percent), added in two stages (before pasteurization and at same time with starter culture) was studied on the microstructure and acidification characteristics of yogurt during fermentation time. The results showed that different levels of Spirulina biomass had significant effect on acidification kinetics parameters of yogurt samples (p
