Arman Naderi; Soheila Zarringhalami
Abstract
[1]Introduction: Bread is an important staple food widely consumed all over the world including Iran. The consumption of traditional breads in Iran, including Barbari, Sangak, Taftoon and Lavash, is steadily increasing because of its convenience and being a ready-to-eat food product normally consumed ...
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[1]Introduction: Bread is an important staple food widely consumed all over the world including Iran. The consumption of traditional breads in Iran, including Barbari, Sangak, Taftoon and Lavash, is steadily increasing because of its convenience and being a ready-to-eat food product normally consumed at breakfast, lunch and dinner. Hence, fortification of several types of bread with other cereals, pseudo cereals, legumes and oil seeds flours, has received considerable attention. Sesame, although referred to as “seed of immortality” and “queen of oilseeds” is considered as a rich food as it has a high nutritive quality. Apart from being a prominent oilseed (45-50%), sesame seeds are a rich source of protein (18–40%). Also, sesame was reported as a rich source of vitamins and minerals. Therefore, in the current study, the effect of wheat flour fortification with sesame flour at the ratio of 0, 5, 10 and 15 % on flour, dough, Sangak and Barbari samples properties was evaluated. Material and Methods: Proximate analysis of flour samples (sesame, wheat and composite flour samples) including acid value, moisture, ash, protein and wet gluten contents of the flour samples were determined according to the AACC methods. Water absorption, dough development time, dough stability time, degree of softening and the ratio between resistance to extension and extensibility (R/E), of prepared dough samples were determined according to AACC 21-54 and AACC 10-54 standard methods. After 2 h of bread baking the crust color parameters (L*, a* and b*) were determined using the Hunter–Lab Color flex Colorimeter (Hunter Associated Lab, Inc., Reston, VA, USA). Crumb Hardness was also measured 2 h after baking using a texture analyzer (Texture Analyzer, Brookfield, CT3, USA). The organoleptic characteristics (taste, aroma, color, texture and overall acceptability) of the prepared bread samples were evaluated by 15 trained panelists familiar with the traditional bread usually consumed, using 5-point hedonic scale (5 = like extremely, 1 =dislike extremely) test. The data was analyzed by one way analysis of variance (ANOVA). A multiple comparison procedure was performed by Duncan’s new multiple range test using SPSS Software. Significance of the difference was defined as p <0.05. Results and Discussion: According to the results obtained from flour samples analysis, sesame flour contained higher amounts of protein, lipid and ash and low amount of moisture and gluten than wheat flour. Furthermore, with increasing the amount of sesame flour, ash and protein contents of flour samples were increased, but their moisture and gluten contents were decreased. Furthermore, Farinograph parameters including water absorption and stability were decreased, but dough development time and degree of softening were increased with increasing the amount of sesame flour in the formulation. The results of Extensograph test also, showed the R/E ratio, which indicates dough stability during fermentation, was decreased when the sesame flour content increased. Therefore, the addition of sesame flour induced to weaken the gluten network formation in dough samples. The qualitative characteristics results of bread samples showed that addition of sesame flour to bread formulation tends to decrease crumb hardness and had no effect on color attributes (L*, a* and b*). Sensory evaluation results showed the higher total acceptability of Sangak and Barbari bread samples containing 10 and 5 % of sesame flour, respectively. In these ratios the color and texture of bread samples were also similar to related control bread samples. According to the results obtained in the current study and based on the functional properties of sesame flour (rich source of oil, protein, minerals, vitamins and antioxidant compounds) that reported by several previous studies, addition of 5 and 10 % of sesame flour in large scale production of Barbari and Sangak breads is recommended. Due to the high consumption of Sangak and Barbari breads in Iran, fortification of these breads can be effective in providing the daily needs of several nutrients.
Firooze Bazrafkan; Soheila Zarringhalami; Ali Ganjloo
Abstract
Introduction: In recent years special attention has been paid to the use of natural sources contain healthy bioactive compounds. Fruit and vegetable juices are a good source of many biologically active compounds, particularly vitamins, minerals and phenols. Phenolic compounds are secondary metabolites ...
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Introduction: In recent years special attention has been paid to the use of natural sources contain healthy bioactive compounds. Fruit and vegetable juices are a good source of many biologically active compounds, particularly vitamins, minerals and phenols. Phenolic compounds are secondary metabolites widely found in fruits, mostly represented by flavonoids and phenolic acids. Phenols are known for their antioxidant, anticancer and cardio-protective properties among bioactive compounds. The health benefits of these phytochemicals are directly linked to a regular intake and their bioavailability. Berries with dark blue or red colors have the highest bioactive compounds and antioxidant capacities among all common fruits and vegetables. Anthocyanins which are one of the largest and most important group of water-soluble pigments in most species in the plant kingdom are largely responsible for diverse pigmentation from orange to red, purple and blue fruits, such as: blackberry, red and black raspberries, blueberries, bilberries. White mahlab (Prunus mahaleb L.) fruits with a dark red color, which known also as English cherry, Rock cherry, St. Lucie cherry, of the Rosaceae family, subfamily Prunoidae, is a deciduous tree with 1–2 m high. Mahaleb cherry tree which grows abundantly in West Asia such as in Iran used just as basic link for cherry trees because of bitter taste of their fruits. In order to reduce the bitterness and improve the taste of mahaleb juice, a debittering process is considered as an effective solution to overcome the commercial application problem. Several debittering techniques have been used to reduce the content of bitter compounds, such as biodegradation by enzymes, addition of bitterness suppressing agents, ultrafiltration.
Material and Methods: All chemicals used were analytical grade and purchased from Merck (Darmstadt, Germany) and Sigma-Aldrich (St. Louis, MO. USA).
Selected microorganisms including Staphylococcus aureus (PTCC: 1112), Escherichia coli (PTCC: 1338), Aspergillus flavus (PTCC: 5004) and Penicillium chrysogenum (PTCC: 5037) were obtained from the Iranian Research Organization for Science and Technology (IROST), Iran.
The ripened fruits of mahaleb were collected from the orchard of Zanjan University, and transported to the laboratory. Harvest involved a random sampling from 5 trees. Stem and leaves were then discarded, and fruits stored at -18 ℃ until further use.
Frozen fruits were removed from the freezer, thawed and pitted. The fruit juice was obtained using a domestic juicer (Moulinex PC302, France). The juice was filtered through a stainless steel sieve (1 mm) to separate pomace from juice. The juice obtained was placed in dark glass bottles until further analysis.
Vitamin C content was determined using spectrophotometric method. Total phenolic content of the fruit juice was determined using Folin–Ciocalteu’s assay. Total flavonoid and anthocyanin contents of the fruit juice were determined according to the colorimetric assay at 510 and 526 nm, respectively. Antioxidant activity was determined using Diphenyl Picrylhydrazyl (DPPH) free radical scavenging and reducing power of H2O2 methods.
Antimicrobial activity of mahaleb juice against E. coli, Staphylococcus aureus, Aspergillus flavus and Penicillium chrysogenum was evaluated using agar well diffusion, and minimum inhibitory concentration and minimum bactericidal concentration was determined using broth microdilution and surface methods.
Results and Discussion: According to the result obtained, vitamin C, total phenolic, total flavonoid, total anthocyanin content was 39.26±0.01 mg/100 mL, 303.00±0.06 mg GAE/100 mL, 17.00±0.01 mg Rutin/mL and 871.63±0.93 mg Cyanidin/100 mL, respectively. Free radical scavenging activity and reducing power of H2O2 was 72.30% and 6.33%, respectively. Based on these results the white mahaleb juice had bioactive compounds such as other fruits with blue and purple color. According to other researchers there was a higher positive correlation between the amounts of carotenoids, total phenolics and anthocyanins and the antioxidant activity. Of course, it should be noted that several factors such as the plant growth region and the harvest period might have an impact on plant growth and metabolite concentration. Some studies also showed that dark red sour cherries contain higher total phenolic and total anthocyanin content compared to sour cherries with lighter red color. Therefore, mahaleb juice which was used in the current research with dark blue color and high total phenolic and anthocyanin content have high antioxidant activity.
The results also revealed that mahaleb juice had no inhibitory effect on Aspergillus flavus and Penicillium chrysogenum whereas the minimum inhibitory concentration on 102 CFU/ml of E. coli and Staphylococcus aureus was obtained at 0.9 and 0.8 % concertation of mahaleb juice. In addition, no minimum bactericidal concentration was observed. So, mahaleb juice likely has no or little antifungal activity compared to antibacterial effects. Previous studies also showed that antimicrobial activity of many extracts related to their phenolic compounds and anthocyanins. Blueberry methanol extract was shown strongly inhibit the pathogenic bacteria, such as E. coli O157:H7. The antimicrobial properties of blueberry morelikely is due to the compounds of monomeric phenolics, anthocyanins and proanthocyanidins. Therefore, mahaleb juice as a source of natural bioactive compounds such as vitamin C, phenols, carotenoids and anthocyanins is recommended as functional food in industry, especially, after debittering.