Zahra Sheikholeslami; Mahdi Karimi; Toktam Hejrani; Mehdi GhiafeDavoodi; Hamed Fatemian
Abstract
Introductıon: Hydrocolloids have been employed for reduction of moisture migration from the crumb to crust, added to the formulation, improved texture, prevent ice Crystallization and delay staling (Ba´rcenas et al 2003, 2004, Hager, and Arendt, 2013). However, given the importance of their role still ...
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Introductıon: Hydrocolloids have been employed for reduction of moisture migration from the crumb to crust, added to the formulation, improved texture, prevent ice Crystallization and delay staling (Ba´rcenas et al 2003, 2004, Hager, and Arendt, 2013). However, given the importance of their role still trying to find new resources will continue to create the best quality. Today, researchers introduced new technologies such as modified atmosphere packaging, frozen technology and using different additives to produce bread with higher quality, longer shelf life and high nutritional value. Production of the part baked frozen bread is a method which interrupted baking process, the first stage is the crumb formation and the crust color is not developed. The aim of this study was to evaluate the effect of Ocimum Bacilicum and tragacanth at 3 levels (0, 0.3 and 0.5%) (W/W flour basis) on the quality of part-baked Barbari bread after frozen storage and re-baking.
Materials and methods: The Ocimum Bacilicum seeds were cleaned, then were firstly soaked in distilled water to obtain a water to seed ratio of 37:1 at 40˚C and pH 7. Separation of the hydrocolloid from the swollen seeds was achieved by passing the seeds through an extractor equipped with a rotating plate that scraped the gum layer on the seed surface. The extracted solution was then filtered and dried in an air forced oven at 60˚C and finally the powder was milled, sieved using a mesh 18 sifter, packed and kept at cool and dry condition (Karazhiyan et al., 2010, Sahraiyan et al., 2013). Tragacanth purchased from the local market as a tape shape after milling and sieve (70 mesh) were used. Bread prepared as part baked, freezing in -18°C and storage for 15 days, after this time samples were thawing and full baked. The test includes moisture content, specific volume, porosity, firmness, image analysis and sensory properties was measured. For Data Analysis used SPSS software and Duncan test, for mean comparisons.
Results and discusions: The results obtained from volume, texture, moisture content and sensory properties showed Tragacanth gum at 0.5 concentrations and Ocimum Bacilicum gum at 0.5 levels improved moisture content. Using tragacanth at 0.3% and Ocimum Bacilicum gums at 0.5 % concentration improved the specific volume, porosity, firmness, and sensory properties. The hydrocolloids are highly hydrophilic nature, it made hydrogen link between the water available in the system, prevent the movement of water from crumb and improved the firmness and improved the quality of bread (Manadala et al., 2008). The hydrocolloids capable to strengthen the gluten matrix surrounded cell gas as result maintenance them during part baked and frozen storage. Hydrocolloid, coalescence of gas cells as a result of expansion during the proofing step and increase the volume and porosity of bread (Shillini & Laxemi, 2007).
Conclusion: Addition of Ocimum Bacilicum and tragacanth to bread recipe improved the crumb texture of the bread that obtained from part-baking, frozen storage and re-baking. In addition, the presence of gums improved the specific volume, texture and the overall quality of the product during frozen storage, removing the negative effects of that process conditions. The Ocimum Bacilicum in comparison of tragacanth had the greater concentration effect on PBF Barbari bread on improved the quality. The interaction of tragacanth and Ocimum Bacilicum (0.3 and 0.5 %) respectively had the best result to improving the all parameters that investigated in part baked and freezing storage of Barbari bread. This study provides insights into the complexity of interactions between tragacanth and Ocimum Bacilicum as a new source of hydrocolloids and their combined influence on bread characteristics, thereby serving as a guide for future research on the other bread
Seyed Ali Mortazavi; Zahra Sheikholeslami; Mehdi GhiafeDavoodi
Abstract
Introduction: Bread stales and unfortunately it is a certainty and causes significant product waste all over the world.Staling results in loss of important sensory parameters of bread, like flavor and texture, and it is a consequence of a group of several physical–chemical changes occurring during ...
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Introduction: Bread stales and unfortunately it is a certainty and causes significant product waste all over the world.Staling results in loss of important sensory parameters of bread, like flavor and texture, and it is a consequence of a group of several physical–chemical changes occurring during bread storage that lead mainly to an increase of crumb firmness and loss of freshness (Gray and Bemiller 2003). At 21th century freezing technology introduced to bakery industry in order to increase bread shelf life, access fresh bread with a minimum need for equipment and skilled personal at any time.The current trend in the baking industry is to use frozen dough to manufacture quality products because it can be quickly transformed into fresh baked product. However, the use of frozen dough has certain disadvantages such as its variable performance and loss of stability over long-term frozen storage (Ribotta and Le Bail 2007). Research has shown that ice crystallization and recrystallization causes physical damage to the gluten network, leading to changes in the rheological properties of the frozen dough. Water available for freezing forms ice crystals that injure yeast cells (Mazur 1968). Gums trap free water and control moisture migration.Furthermore, Ward and Andon (1993) mentioned that gums such as carboxymethyl cellulose, carrageenan, gum arabic, and locust bean gum may be used to alleviate the problems associated with frozen dough. Numerous studies report that enzymes play key roles in bread making such as increasing loaf volume, producing finer crumb cells, and extending shelf-life. Amylase improved frozen dough bread quality; the enzyme allowed us to obtain breads from frozen dough with high specific volume and low crumb firmness(Ribotta and Le Bail 2007). Therefore, the aim of this work was to study the effect of guar gum and alpha amylase on frozen dough and the influence of them on the minimization of the damage caused by frozen storage. Materials and methods: Wheat flour sample (cvs, Pishgam) with 10.52% moisture, 10.8% proteins ,79% ash, 26.7% wet gluten, was obtained from silo No.3, Mashhad, Iran. Bread recipes also contained active dry yeast (Razavi Co., Mashhad, Iran), vegetable oil( Ladan Co. Behshahr, Iran), salt and sugar (Local market). Amylase enzyme (25 klu/g) and guar gum afforded from Novozyme and Rodhia CO respectively. The bread formula used for Barbari bread consisted of flour (100 parts), compressed yeast (2 parts), salts (2 parts), sugars (1parts), vegetable oil (1 part) and water (based on water absorption at 500 BU). Guar and amylase replaced in bread formulation at two levels (0.4 and 0.8%), and (0.05. 0.07 %) respectively. Bread was part baked in an electric oven with an incorporated proofing chamber (Zuccihelli, forni, Hal, Italy) at 210˚C for 7 min to obtain texture structure before starting coloring reaction. Barbari bread sample were packaged in polyethylene bags and frozen in a blast freezer. After storage at -18°C for 15 day, PBF bread was thawed at room temperature for 10 min and rebaked at 260°C for 8 min. The fresh bread baked at 230 °C for 15 mines (Ba´rcenas and Rosell, 2007). Specific volume , porosity, texture evaluation, image analysis (L*a*b*) and sensory evaluation of bread were measured using AACC methods (2000). Results were reported as the average of three replications (all treatments were evaluated in three batches). The data obtained were statistically treated by a complete randomized design (factorial) analysis while the means were compared by the Duncan’s test at a significance level of 5%, in both cases using SPSS statistical software (version 17). Result and discussion: The results showed that frozen storage had significant effects on the specific volume, moisture content, crumb hardness, sensory properties and bread color. Addition of gum and enzyme to bread recipe improved bread quality, alone and in combination. The presence of guar and amylase removing the negative effects of process conditions. Addition of guar at 0.4% improved specific volume, textural properties, color, sensory score and decrease bread firmness. Also using of amylase in 0.07%,increased bread quality. When guar used in combination with amylase, the synergistic effect was observed. The best result, obtained with 0.4% guar and 0.07% amylase. Conclution: In summary, the result of this study has shown that textural and sensory properties of part baked frozen bread were poor. Addition of guar gum increased specific volume and sensory score of bread. Guar in 0.4% concentration in comination with amylase in 0.07%, were more effective and it could introduce as a improver for part baked frozen bread.
Amir abbas Omidfar; Esmaeil Atayesalehi; Zahra Sheikholeslami
Abstract
Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt ...
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Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt was used as an additive to improve the quality and shelf life of bread (including Barbari bread). The most common type of the malt used in the world is barley malt. This is because of the utilization of most of the malt product in the world, including to produce beverages based on malt, particularly alcoholic and non-alcoholic onesand considering that the malt made from barley grains has the best quality among the other cereals to produce these products.Therefore, discussion on other malted cereals would be find less in the literature especially corn malt (which has not a good quality to produce malted beverages). On the other hand, corn is the main cereal widely consumed in the world after wheat and rice. The purpose of this study was to produce Barbaribread usingcorn malt (powder or extract) as an additive to increase shelf-life, volume and softness, as well asimprove the sensory characteristics (staling, total appearance, softness, texture, brain color, crust color, crust appearance, flavor and odor). Materials and methods: For this purpose, bakery flour with 85% extraction rate, Dent corn (Zea mays var. Indentata), Saccharomyces cerevisiae as an active dry yeast, malt extract or powder and other additives, used in the formulation of Barbari bread. To evaluate the sensory characteristics, the bread samples were analyzed by 15 trained referee. The results were based on a factorial arrangement with two factors completely randomized design that the first factor is type of corn malt (powder or extract) and the second one is amount of corn malt (in four levels of 0, 0.5, 1.0 and 1.5 percent) was evaluated. Results & Discussion: The resultsshowed that the treatment with 1.5 percent extract corn malthas the highestspecific volume(with an average of 4.5) and thetreatment with 1.5 percent powderhas the lowestspecific volume(with an average of 3.67). And just the treatments with 1 and 1.5% malt extract in compared with the control sample showed significance differences (P
Amir Pourfarzad; Mohammad Hossein Hadad Khodaparast; Mahdi Karimi; Seyed Ali Mortazavi
Abstract
The effect of adding sodium stearoyl-2-lactylate (SSL) and propylene glycol (PG) (0 - 0.5 g/100g) to emulsifier gel formulation on the crumb and crust characteristics of Barbari bread fortified with soy flour in order to optimize these characteristics were evaluated. The obtained results showed that ...
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The effect of adding sodium stearoyl-2-lactylate (SSL) and propylene glycol (PG) (0 - 0.5 g/100g) to emulsifier gel formulation on the crumb and crust characteristics of Barbari bread fortified with soy flour in order to optimize these characteristics were evaluated. The obtained results showed that addition of SSL caused an increase in the crumb and crust L* and cell density. The a*, b*, average cell size and porosity of bread crumb decreased by increasing SSL. PG had increasing effect on b* of crumb and decreasing effect on L* of crust. However, no significant difference (p ≥ 0.05) was observed in a* and b* of crust. The results for optimization using central composite design suggested that a mixture containing 0.5 g/100g of SSL and 0.5 g/100g of PG could be a proper improver gel to achieve the best characteristics.
