Food Technology
Yazdan Moradi; Mansoreh Ghaeni; Haleh Hadaegh
Abstract
Introduction
Seaweeds contain a high amount of protein, essential amino acids, vitamins, minerals, unsaturated fatty acids such as arachidonic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), natural pigments, macro and micro nutrient compounds. Microalgae Spirulina (Spirulina ...
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Introduction
Seaweeds contain a high amount of protein, essential amino acids, vitamins, minerals, unsaturated fatty acids such as arachidonic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), natural pigments, macro and micro nutrient compounds. Microalgae Spirulina (Spirulina platensis) is a species with high nutritional value. About 60% to 70% of the dry weight (Spirulina platensis) is protein, which has all the essential amino acids. This is a cyanobacterial microalga that is cultivated all over the world and used as a supplement in the human diet in the form of tablets, powder and cookies, bread, salad and soup. Several studies have been conducted in the field of investigating the effect of microalgae addition in food products. The purpose of the current research was to investigate the effect of this microalgae powder on sensory, physical, protein and iron properties of three different products of bulk bread, cake and layered sweets with different formulations.
Materials and Methods
Spirulina microalgae dry powder in 0.25%, 0.5%, 0.75%, 1% and 1.25% was added to the formula of three products: bulk bread, layered pastry, and cake. From each product, a sample without microalgae powder was also prepared and considered as a control. The treatments were evaluated in terms of sensory, color, texture, protein and iron content. Sensory evaluation was carried out by 30 panelists using 7 hedonic points to evaluate the color, flavor, texture, smell and overall acceptance. The color of the surface of the samples was done with a Minolta Chroma Meter (CR-300 Minolta Japan). The results calculated based on L* (whiteness/darkness), a*(redness/greenness) and b*(blueness/yellowness). Hardness of samples was measured with Texture Analyzer TA-XT2 (Stable Micro Systems, Surrey, England) and P/0.5 cylindrical probe (12.5 mm diameter) with 30 kg load cell. Protein of the samples was measured by Kjeldahl method and the amount of iron was measured according to the standard method of AOAC 999.11. All analyses were performed in three repetitions and one-way ANOVA and Tukey's test were used to compare the means.
Results and Discussion
The results showed that the behavior of spirulina microalgae in changing the characteristics of the three products is different, and this difference is especially significant in sensory characteristics. The addition of spirulina microalgae increased the amount of protein and iron in different treatments. This increase for protein in bread, cake and sweets was about 1, 0.6 and 1.2 percent, respectively. Also, the amount of iron in treatments containing microalgae in bread, cake, and layered sweets was 4, 5, and 3 mg/kg, respectively. Spirulina microalgae is basically known as an aquatic plant with high protein and iron. The microalgae used in this research contained a high amount of protein (67.97%) and 29.5 mg/100 grams of iron, so adding this microalga to the samples increased the amount of protein and iron. Sensory evaluation of the samples showed that all three products had an acceptable acceptance score. However, in comparison among the three products of bread, cake and layered sweets, bread had a lower score than the other two products. The instrumental analysis of L*, a*, b* color indices showed that the increase of spirulina caused green color in the treatments and this color change is more significant in the bread sample. Also, the results of texture analysis showed that the addition of spirulina reduces the hardness of samples containing spirulina. It can be concluded that spirulina microalgae can be used to improve texture, color, and also increase the amount of protein and iron in products.
Food Chemistry
Ahmad Ehtiati; Massoumeh Mehraban Sangatash; Reza Karazhyan; Zahra Nazari; Farzad Sadeghi
Abstract
Introduction: Shortening is an important ingredient of bakery products, especially the ones with less developed gluten network like cakes and cookies . Shortening thermo-rheological properties are related to the presence of high levels of saturated fatty acids which have the capability of making ...
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Introduction: Shortening is an important ingredient of bakery products, especially the ones with less developed gluten network like cakes and cookies . Shortening thermo-rheological properties are related to the presence of high levels of saturated fatty acids which have the capability of making crystals at room temperature which melt during baking. Consumption of high saturated fatty acids increases the risk of coronary disease. Moreover, hydrogenation is a usual technique for elevating the saturated fatty acid content of vegetable oils. Lowering the saturated fatty acid content of a shortening results in the shortening with less functionality. Transition of an oil physical properties to those of a semi-solid structure can be done using low- or non-digestible oil gelators called oleogelation. Ethyl cellulose is a polymer with oil gelation capabilities at low concentrations. However, its oleogels are firm and brittle, so some low-molecular-weight gelators can improve its texture and increase its plasticity to mimmic commercial shortening functionality. In this study, the functionality of an oleogel based on ethyl cellulose, stearyl alcohol, stearic acid and sorbitan monostearate was evaluated as commercial shortening substitute in cake formulation. Materials and Methods: Based on previous studies and preliminary experiments, an optimized oleogel formulation was prepared as shortening, composed of ethyl cellulose (6.4%), stearyl alcohol:stearic acid (70:30) (7.5%), sorbitan monostearate (0.1%) and canola/soy mixture oil (75:25 ratio) (86%).The gel was formed by heating up the mixture to 150 °C for the complete solvation of the gelator compounds and gradual cooling to room temperature. In the next step, commercial shortening was substituted with the oleogel shortening at 0, 25,50, 75 and 100% in the cake formulation. Moisture content, water activity, specific volume, crust color, Lab color space indices based on image processing, porosity based on crumb image analysis, TPA parameters and sensory attributes were determined and compared using one-way analysis of variance and LSD mean comparison test. Results & Discussion: The results showed that there was no significant difference in the moisture content, water activity and specific volume of the cakes prepared with the oleogel shortening with the one prepared with commercial shortening. This reveals that the oleogel shortening functionality was acceptable compared with commercial shortening. In terms of crust color, there was no significant difference in the lightness index (L*) and red-green range (a*) indicators between different samples and only in the yellow-blue range (b*) index, the cake with 100% substitution showed a lower value than the control. For the porosity index, there was no significant difference between the five samples, proving the oleogel shortening can induce sufficient air bubbles generated during batter mixing and its preserving effect during baking. Examining the texture of the cake samples showed that the texture hardness and springiness indices decreased with a rise in the level of commercial shortening substitution, while the cohesiveness index did not differ significantly. The latter indicated that the oleogel shortening effectively shortened the gluten network; thus, it can be said that the same commercial shortening functionality is attainable using less oleogel shortening content. Furthermore, as the percentage of the commercial shortening substitutes increased, due to texture softening, the chewing energy of the samples decreased resulting in a better mouthfeel. Finally, sensory evaluation of the cake samples did not show a significant difference in taste, texture, appearance, color and overall acceptance based on scores obtained from ten untrained evaluators. In conclusion, the use of oleogel shortening instead of commercial shortening with high saturated fatty acid content in cake formulation not only can result in a cake with acceptable properties at 50% replacement level, but also can replace commercial shortening even up to 100%.The latter just lead to a softer texture. Optimization of the cake formulation based on the oleogel shortening would specifically result in a cake with better properties, while it has significantly lower saturated fatty acid content and nearly zero trans fatty acids.
Mehran Alami; Bahareh Fathi
Abstract
Introduction: Millet is one of the cereals resistant to drought, pest and disease and has a short growing season. As the world's population grows and water resources decline, this agricultural product will increasingly become- important for human use in the future. Millet is gluten-free grain and can ...
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Introduction: Millet is one of the cereals resistant to drought, pest and disease and has a short growing season. As the world's population grows and water resources decline, this agricultural product will increasingly become- important for human use in the future. Millet is gluten-free grain and can be used to produce special food for celiac patients. Due to the low quality of baking products made from gluten-free cereals, additives and physical treatment of flour can be used to improve the baking properties. Therefore, in the present study, heat-moisture treatment of millet grains was used as a method to modify the flour properties. Materials and Method: Proso millet (Panicum miliaceum L.) was dehulled using a stone mill and then moistened to 20, 25 or 30% of moisture by spraying sufficient distilled water, mixing and keeping in polyethylene bags at 4°C overnight. The moistened grains were poured into glass containers and heated in an oven at various temperatures (100 or 120 ° C) for 3 h. After heating, the samples were removed from the containers and dried at about 40°C until about 9% moisture content. The samples were then milled and passed from the screen with standard mesh 80. In this study, cakes were prepared from untreated and treated millet grain. The specific gravity of batter was measured by dividing the weight of a specific volume of batter to the weight of the similar volume of water. Batter viscosity was determined by Brookfield viscometer. Cake volume was measured by the rapeseed displacement method. Color of cake crumb and crust were determined by scanner and image J software. The oven method was used for measuring cake moisture. The hardness of cakes was evaluated by texture profile analyzer. For study of the microstructure of cakes, scanning electron microscope (Hitachi) was applied. In this study, the effects of two factors including moisture of heat-moisture treatment (at 3 different levels) and temperature of heating (at 2 different levels) on the batter and cakes properties were studied by a completely randomized design. Statistical analyses were done via analysis of variance (ANOVA) and Duncan’s multiple range tests for significance at p<0.05 using SAS 9.1 software. Results and discussion: The low specific gravity shows the better aeration of cake batter which can result in greater cake volume. Heat-moisture treatment of millet grains reduced the specific gravity of the cake batter so that the specific gravity of the untreated millet flour batter was the highest. The low batter viscosity reduces the cake volume because the batter cannot keep trapped air bubbles inside it and when the batter is placed in the oven, these bubbles move up to the surface of batter and they get out of the cake. However, a very viscous batter also cannot produce high volume cakes due to the limited expansion of the batter. Therefore, the optimum and appropriate viscosity of the batter is necessary for the production of large volume cakes. Heat-moisture treatment of millet grains significantly increased the viscosity of the batter (p<0.05) so that the lowest viscosity was in the control sample and the highest viscosity was in the treated sample at 30% moisture and 120°C. The samples treated at lower moisture and temperature had higher cake volume compared to the control sample, while the treated samples at higher moisture and temperature showed no improvement in volume. Millet flour treated at 30% moisture and 120°C significantly reduced cake volume (p<0.05) and this effect may be due to excessive viscosity of the batter which prevents the batter expansion in the oven. Increasing the treatment temperature and moisture significantly increased the darkness and redness of the cake color. However, at the baking day and during storage, there was no improvement in the texture and moisture content of the cake crumb after heat-moisture treatment of millet grains. The scanning electron micrographs of raw and treated millet cake showed that heat-moisture treatment of grains increased the uniform and fine cavities in the cake texture. Furthermore, in the cake prepared from treated millet, the gelatinized starch granules are found in the greater numbers.The development of gluten-free bakery products has a growing market worldwide. Therefore, food industry specialists are looking for the production and improvement of the quality of these products. Due to the increasing consumer demand for non-additive foods, there is a growing interest in the physical treatment of cereals as it changes the starch performance without the addition of external ingredients. In this regard, the results of the present study revealed the ability of heat-moisture treatment to modify the performance of millet flour for application in gluten-free product formulations by improving their qualitative properties. Application of heat-moisture treated millet increased cake batter viscosity and air penetration and reduced its specific gravity. Heat-moisture treatment of millet grain at low moisture and temperature improved cake volume. However, the treatment of millet grains did not improve texture and moisture content of the cake during storage. Study of microstructure of the cakes showed that the heat-moisture treatment of millet grain increased the uniform and fine air cells in the cake structure and also the starch granules were more gelatinized. According to the results of this study, heat-moisture treatment of millet grains at 25% moisture and 100 ° C improved quality parameters of batter and cake compared with control.
Sara Jamehdor; Sara Movahhed; Babak Ghiassi Tarzi
Abstract
Introduction: The cake is considered as the bakery products and has the different kinds with different calorie and often high calories in the kinds of cakes is due to the oil, eggs and sugar that is used in its formulation .In the present study the carbohydrate-based fat replacements are used instead ...
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Introduction: The cake is considered as the bakery products and has the different kinds with different calorie and often high calories in the kinds of cakes is due to the oil, eggs and sugar that is used in its formulation .In the present study the carbohydrate-based fat replacements are used instead of fats for consuming. The flaxseed with the scientific name of "Linum usitalissmum" is an annual plant from the family of flax and in terms of nutritional value it is a good source of omega-3 (alpha-linolenic acid, ALA), Lignans (such as phyto-estrogenic), fiber, protein, minerals and vitamins. The high amount of water absorption by flaxseed in bakery products leads to increase the volume and improve the quality of bread and also increase the shelf life of the product produced. The oat is a plant from the family of grains and from the genus of "Avena" called in English "Oat". One of the major compounds in the oat is β-glucan. The said compound is the common name of glucose polymers that is found in the endosperm cell walls of barley and oat and usually forms 3-7% of the seed weight and is classified as soluble dietary fiber and carbohydrate-based fat replacements. The purpose of this study was to add different levels of flaxseed and oat bran as a part of fat replacement in cake. Different Levels of shortening were replaced with Oat bran and flaxseed powder and their effects on the chemical characteristics, volume, color, staling and sensory characteristics of the cakes were examined.
Materials and methods: Raw materials needed to bake a cake included the null wheat flour (Mehbod Company) with extraction rate of 70%, sugar (Pardis Company), nonfat dry milk (IDI France Company), egg white powder (Talavang Company), table salt (Golha company), baking Powder (Golhan Company), oil (Ladan Company), flaxseed and oat bran (Sarv Company). Chemical tests performed on wheat flour, oat bran and flaxseed meal and samples of cakes included the measurement of moisture, ash, protein, fat, fiber, peroxide and pH were performed. For the production of cake the raw materials were prepared and were weighed. Then, the oil and sugar mixed for 2 minutes and then some water was added and mixed for 2 other minutes. Then, the null wheat flour, oat bran and flaxseed powder sieved with other materials were mixed. Finally, the cake was added to the mold and located in the tunnel oven at 170°C for 35 minutes for baking. in all the tests the control treatment (cake containing 100% fat and null wheat flour) with the code of C, the treatment containing the oat bran and flaxseed with the ratio of 20:40 (weight– weight of fat consumed) plus 40% of fat with the code of A1, the treatment containing the oat bran and flaxseed with the ratio of 40:20 (weight – weight of fat consumed) plus 40% of fat with the code of A2, the treatment containing the oat bran and flaxseed with the ratio of 30:30 (weight– weight of fat consumed) plus 40% of fat were determined with the codes of A3 revealed. The method proposed by Henry Simon British Company and device of volumeter were used to determine the volume of cake samples produced. The test of determining the color the Hunter Lab device was used. In order to determine the amount of staling of the cake samples, the device of evaluating the texture or Instron was used. In this study, examined by 10 trained evaluators was used for organoleptic test of samples. In determining the amount of staling in the cake samples produced the sensory method was used. This test was conducted at the intervals of 3, 7 and 10 days after baking of the samples. In order to investigate the quantitative characteristics of data considering to the presence of four treatments and three replications, randomized block design, the analysis of variance and the software "SPSS", version 16, were used.
Results & discussion: The amount of protein and fiber in treatment of A1 and in the control treatment was the highest and the lowest, respectively. In addition, the amount of ash and moisture in the treatment of A2 and in the control treatment was the highest and the lowest, respectively. The treatment of A1 and the control samples had the highest and the lowest amount of peroxide, respectively. Results of specific volume test indicated that the treatment of A2 and the control samples had the highest and the lowest amount of specific volume, respectively. The results of colorimetric test of cake samples indicated that the lightness (L*) in the control cake and in the treatment of A1 was the lowest and the highest amount, respectively. Moreover, the amount of redness in treatment of A1 and control treatment was the highest and the lowest, respectively. The amount of yellowness in the control treatments and treatment of A2 was the highest and the lowest, respectively. The results of evaluating the sensory characteristics of cake samples produced by panelists showed that most sensory characteristics of the cake samples containing flaxseed and oat bran compared with the control had higher rating. The results of staling test in the cake samples produced by sensory method showed that the control treatment had the highest amount of staling and the treatments of A1, A2 and A3 had the lowest amount of staling, respectively. The results of staling test using device method showed that the control treatment had the highest amount of staling and the treatments of A1 and A2 had the lowest amount of staling, respectively. Finally, the treatment of A2 was introduced as the best treatment. In the present study, oat bran and flaxseed seed were used as a part of carbohydrate-based fat replacements in the cake to produce a healthier products with less fat and better nutritional compounds while improving the qualitative characteristics.
Fatemeh Bahrami Maghsudbeki; Hajar Abbasi; Mohammad Goli
Abstract
Introduction: Legumes are suitable sources in nutraceutical properties due to existence of anticancer, antioxidant and also significant antimicrobial substances. Different processing such as soaking, peeling and germinating improves nutritional value and bioavailability of minerals such as calcium, iron ...
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Introduction: Legumes are suitable sources in nutraceutical properties due to existence of anticancer, antioxidant and also significant antimicrobial substances. Different processing such as soaking, peeling and germinating improves nutritional value and bioavailability of minerals such as calcium, iron and phosphorus content of legumes and based on the literature review, germination is the best method among the others. The results of previous researches demonstrated significant improvement of nutraceutical and farmoceutical properties of products due to germination. In legumes, sprouted lentil has higher nutritional value such as minerals and essential amino acids than others. Cereal based products, especially products of wheat flour such as bread, pastries, biscuits and etc are used generally as a staple food around the world. Cake is one of the widely used confectionary cereal based product that its nutritional quality is important in public health. According to deficiency of wheat flour from many essential amino acids and important minerals such as iron, the aim of present study was to employ natural enrichment of cake with sprouted lentile and improving the qualitative characteristics of products using active gluten and hemicellulase enzyme. Due to the existence of problems in enrichment of wheat flour with iron due to difficulties in uniform distribution of particles and creation of unsuitable organoleptic properties in the products, currently, iron enrichment is limited to whole flour in Iran. Therefore, the results of the present research could an alternative way for flour enrichment with iron and other nutrients.
Materials and method: In order to prepare sprouted lentil flour, the “official” lentil variety was prepared and treated at ambient temperature (24°C) and suitable humidity (90%) in dark place in order to germinate and increase the shoot height to 1.5 cm. The sprouted lentils were dried at room temperature in shadow. Then, they were milled and sieved in order to achieve suitable particle size. At the beginning step, sprouted lentil flour and wheat flour were evaluated in terms of protein, moisture, ash, fat and minerals such as iron, calcium, potassium and phosphorus. After numerous pre-tests by experts in cereal technology, the usable quantities of sprouted lentil flour according to organoleptic characteristics of the product, was considered 25% of batter’s flour. Improving the textural characteristics of products due the negative effects of germinated lentils flour was considered using independent variables of present study (hemi-cellulase enzymes at 0, 25 and 50 ppm levels and active gluten powder at %0, %1/5 and %3). Sprouted lentil flour was treated for 30 minutes with enzyme before using in batter formulation. Prepared samples with 25% replaced sprouted lentil with wheat flour and hemicellulase (0, 25, 50 ppm) and active gluten (%0, %1.5, %3) were investigated in terms of volume, bulk density, color properties of crust and crumb, moisture content, textural properties (hardness, cohesiveness and springiness) and also sensorial properties. Prepared product based on optimized formulation according to the results of chemical, physical and sensorial analysis was evaluated in staling rate, the quantities of fat, protein, ash, fiber and minerals such as iron, calcium, phosphorus, potassium and its results were compared to control. Data was analyzed according to the factorial experiments based on completely randomized design by SAS software (version 9.2), and the means were compared by LSD test at 5 significance percent level. Statistical evaluation of sensorial properties was also done based on qualitative method of Kruskal-Wallis.
Results and Discussion: In chemical composition of wheat and sprouted lentil flour, there were significant differences between two samples in terms of protein, ash, and minerals content such as iron, calcium, phosphorus and potassium. But, there was no significant difference in fat content. The quantity of iron in lentil flour was five times more than that of wheat flour, calcium was double, potassium was seven times and phosphorus was six times more than that of wheat flour. Also, sprouted lentil flour showed higher protein content than wheat flour. Addition of sprouted lentils to batter formulation increased moisture content of the sample than the same one prepared only with wheat flour. Gluten and hemicellulase had significant effects on reducing the apparent density of samples and improving the physical, sensorial and textural characteristics of the product. In this regard, the hardness of sample’s crumb were decreased and theirs cohesiveness and springiness were increased significantly. According to the results of the present study, the addition of gluten and hemicellulase enzyme was improved color properties, especially in crust position. Therefore, independent variables were effective in improvement of qualitative properties of products. Finally, the optimal sample based on physical, textural and sensorial evaluation was introduced a sample with 25% sprouted lentil flour, 3% active gluten and 50 ppm hemicellulase enzymes. The optimum sample was closed to wheat control sample in the case of the qualitative characteristics. Comparison of textural characteristics of optimum and control samples during storage was indicated the similar characteristics of them. Sprouted lentil flour was a rich material in fiber with high water binding capacity in technological point. Therefore, it improved moisture retention and softness of texture. As well as, comparison the textural qualitative characteristics of the selected and control samples (prepared with wheat flour completely without additives) was shown a very high affinity in them. The products made with sprouted lentil had significantly higher nutritional value in protein, ash, crude fiber and minerals such as iron, calcium, potassium and phosphorus content than control. The iron content of optimum sample was more than twice of the control. Therefore, the results of the present research are effective in production of the functional product with improved nutritional characteristics. Due to the unique nutritional value of grain, more sprouted bean is recommended to use in food product formulation, and at the same time suitable additives are used for reducing their impact on the textural and sensorial properties of product.
Masoumeh Pourseyed; Ali Motamedzadegan; Jafar Mohammadzadeh Milani
Abstract
Introduction: Converting milk into milk powder increases its shelf life up to almost 1 year, without substantial loss of quality, even at ambient temperatures. Dairy powder is frequently used because of convenience in applications for transportation, handling, processing, and ease of product formulations. ...
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Introduction: Converting milk into milk powder increases its shelf life up to almost 1 year, without substantial loss of quality, even at ambient temperatures. Dairy powder is frequently used because of convenience in applications for transportation, handling, processing, and ease of product formulations. Functional properties of milk powder are important due to its wide range of applications, especially in bakery products requiring desirable texture and moisture content. These functional properties include emulsification, foaming, water absorption, viscosity, gelation, and heat stability. Fresh milk and milk products such as condensed or dried milk which have not been exposed to sufficient heat treatment are not suitable for good quality bakery products as properly heated milk, mainly due to the destruction of proteolytic enzymes by heat, denaturation and coagulation of the proteins, changes in the colloidal properties of the salt and alterations in the oxidation-reduction systems. Kirk (1971) has outlined a list of functional contributions provided by skim milk powder (SMP) in various bakery food products, such as increased absorption, buffering value, lactose color reaction, tenderizing effect, improved body and resilience of crumb. This is in agreement with the results showed by Pyler who added SMP to bread and cake affected. Pyler noted the advantages of lactose in food systems. Lactose mostly affect relative sweetness, browning reaction, protein stabilizing properties, alteration of crystallization patterns, flavor accentuation, selective fermentation, and has nutritional value.
Materials and methods: Yazdi cake was produced using baking wheat flour (from Golha factory), sugar (sucrose), hydrogenated vegetable shortening, baking powder, and baking soda. Eggs were bought the day before baking and refrigerated at 4°C. The dough was prepared in ratio of 30 % oil, 46 % sugar, 50 % water, 11.7 % eggs, 4 % baking powder and 1 % baking soda rather than flour. For improvements of flavor and taste, an equal value of vanilla was added to the whole dough formulations. Skim milk powder containing 1.5 % fat, 3-4 % moisture has bought from Pegah factory. 25 and 50 percent of skim milk powder was also added to the dough. Dough was prepared based on the method of double mixture steps and was baked at 180°C in oven for 30 min. Samples were vacuumed and kept at ambient temperature for further experiments
Result and discussion: The differences in specific volume and consistency of the dough values were found to be significant (p>0.01). According to Baeva studies, there is an inverse relationship between specific gravity and the entry air bubbles in the dough, so the sample with 50% had the lowest specific volume. The consistency of the dough increased significantly by increasing in SMP content (P
Zahra Najafi; Sara Movahhed; Hossein Ahmadi Chenarbon
Abstract
Introduction: Cake is one of the most important and widely used cereals and a product of wheat flour. Usually, high-calorie in a variety of cakes is attributed to oils, eggs and sugar in their formulation. Nowadays, the risk of cardiovascular diseases is increasing in most parts of the world and the ...
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Introduction: Cake is one of the most important and widely used cereals and a product of wheat flour. Usually, high-calorie in a variety of cakes is attributed to oils, eggs and sugar in their formulation. Nowadays, the risk of cardiovascular diseases is increasing in most parts of the world and the demand for using the low fat and low cholesterol foods is increasing due to the relationship between excess fat and various diseases. Therefore, it seems that the partial or complete removal of oil and egg and replacing them with other substances in the formulation of the cake is very important. In recent years, the use of dietary fiber of different sources in food products is increasing due its beneficial effects on human health. Among agricultural products, the residues from the processing of oranges are rich in fiber that can be used as a dietary fiber in the food industry. Fiber is a general term for many different types of carbohydrates that is obtained from plant cell walls and is not decomposed by digestive enzymes in the human body. Formulating the food with citrus fiber could be very beneficial since the exisence of a variety of fiber compounds in the peel of citrus with neutral pH that the property may leads it to be widely used in a variety of foods. Others advantage is that it lead to improve the cooking performance, increase the water binding capacity, the oil absorption and improve the final texture of product with lower costs.
Materials and methods: In this study, the use of citrus fiber was studied in order to improve the structure and nutritional properties of muffin with a new formulation. In this regard, the orange fiber at three levels (0.5%, 1% and 2%) and with 25% of decrease in oil and egg was used in the muffin production process. In this study, the raw materials, including null flour, sugar, liquid oil, eggs, milk, salt, vanilla, baking powder and orange fiber were prepared from France ID Food Company. Two-step mixing method was used to prepare the dough. The cakes were placed at 180 ° C for 30 minutes. In all tests, the control treatment with code T, treatment containing 0.5% of orange fiber with code T1, treatment containing 1% of orange fiber with code T2 and treatment containing 2% of orange fiber with code T3 were determined. First, the chemical tests including moisture, ash, fiber and pH were conducted on the wheat flour. Then, viscosity determination was carried out usinga Brookfield viscometer, Also the density measurement performed on the muffin cake dough. Afterwards, the production of different treatments, the chemical tests including moisture, ash, fiber and pH as well as the staling tests were performed by two sensory and instrumental methods by Instron device and also the organoleptic characteristics (volume, crack, balance of shape, taste and aroma, chewiness, apparent texture, uniformity of pores in the cake center and the color of cake center and the outer shell) were conducted by using five senses on the produced Muffin Cake according to the standard method.
Results and discussion: For statistical analysis of data from physicochemical and sensory tests, completely randomized design and data from staling test from factorial experiment in a completely randomized block design was used and the mean comparisons were conducted by Duncan's multiple range test at probability level of 1% (α=1%) and by using SPSS software, version 16. Considering the results of viscosity and density of the muffin cake dough, the highest amount of viscosity and density belonged to the treatment containing 2% of orange fiber (T3) and control (without orange fiber). The highest percentages of moisture, ash and fiber were calculated for the treatment T3 and the lowest amounts were calculated for control. Also, the highest and the lowest amounts of pH were observed in the treatments of control and T3, respectively. Also, considering the results of staling test by both sensory and instrumental methods and in the intervals of 24, 48 and 72 hours after baking and in all time periods of treatment T3 had the highest score of freshness (delay in staling) and the treatment containing 1% of orange fiber (T2), containing 0.5% of orange fiber (T1) and control (T) had the lowest score of freshness, respectively. The control sample had the highest amount of staling in all days and the amount of staling increased in all treatments over time. It is noteworthy that at all time intervals, the control sample had the highest rate of staling and the staling rate increased for all treatments over time. Considering the results of sensory test, T1 was introduced as the best treatment and in most of the organoleptic characteristics such as taste, flavor, uniformity of pores, chewiness, and overall acceptance had no significant difference with the control sample and was the nearest sample to the control and had the highest score and the highest level of consumer acceptance.
Conclusion: The results showed that adding different levels of orange fiber has a significant effects on physicochemical and organoleptic properties of the muffin cake and replacing 25% of oil and egg used in muffin cake with 0.5% of orange fiber is possible and has enough acceptances.
Bahare Shahidi; Maryam Kalantari; Sareh Boostani
Abstract
Introduction: Grape syrup is a natural sugar source that is obtained by concentration of fruit juice up to about 70% soluble dry matter concentration. Iran is ranked in seventh place in terms of grape production in the world, so there's good potential for converting graph waste to the valuable food products. ...
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Introduction: Grape syrup is a natural sugar source that is obtained by concentration of fruit juice up to about 70% soluble dry matter concentration. Iran is ranked in seventh place in terms of grape production in the world, so there's good potential for converting graph waste to the valuable food products. Grapes with inappropriate appearance can be converted to grape syrup and used as an ingredient in formulation of many food products. Cake is one of the most popular products in bakery and confectionery industry. Cake composed of different components such as flour, oil, milk, baking powder and sugar. Sugar is the main ingredient for making cakes that besides the creating sweet taste, represents numerous functionalities in bakery products. Despite all the benefits of sucrose, because of the association with certain health problems like high blood pressure, cardiovascular disease, tooth decay, obesity and diabetes lots of research is underway to find a suitable replacement for sugar. The challenges ahead when replacing sugar with other sweeteners have forcedthe researchers to provide a sweetener with similar functional properties, taste and quality with sugar. The benefits of grape syrup compared with the sugar are having less crystallization problems, having higher water holding capacity properties and higher perceived sweetness in final product. Due to the mentioned challenges the present study aims to replace sugar with grape syrup in various amounts and to investigate the effects of the replacement on the physical properties of the resulting cakes.
Materials and methods: Grape juice with Brix 68-70 were obtained from local market. Cake flour was also purchased from the local market. In this research four different level of grape syrup (0, 20%, 40%, 60% replacing of sugar with grape juice) were used in cake formulations as a natural replacement for sugar. Preparation of cake batter was carried out using sugar dough method. Consistency and specific gravity of the batters and moisture content, volume, texture, color and sensory properties of the cakes were investigated according to the procedures described in standard methods.
Results & Discussion: The results showed that increasing grape syrup level caused an increase in batter consistency. The main component of the grape juice contains reducing sugars, monosaccharides such as glucose and fructose and there is a small amount of sucrose. Generally most sugars can cause highly concentrated solutions due to their highly water solubility and hydrophilic character. Sugars make hydrogen bonds with water molecules due to their hydroxyl groups, because of the molecular structure of the sugars like sucrose, fructose and glucose, it seems that increasing functional groups in grape sugars compared with sucrose, resulted in the formation of more hydrogen bonds, which caused the reduction in the mobility of free water and therefore make an increase in viscosity of the mixture.According to the results specific gravity of the cake batters increased as the grape syrup level increased. It can be concluded that the addition of the grape syrup to the cake formulation reduces gas storage capacity in the batter and therefore causes the increase in specific gravity of the system. Moisture content of cakes increased with grape syrup addition. Increasing the moisture content in the cake is probably due to competition between moisture- absorbing compounds in the formulation of cakes. The replacement of sugar with grape syrup in the cake formulations decreased the cake volumes. Cake volume is influenced by two main factors including consistency and the specific gravityof the batter. If the batter consistency be too low air bubbles and carbon dioxide that is produced by the decomposition of baking powder will leave the cake out quickly and cake volume will decrease. As mentioned before the saccharides with lower molecular weights tend to absorb more water and caused an increase in batter consistency of cakes prepared from grape syrup compared with the cakes prepared from sucrose. In addition specific gravity of the batter will increase with increasing grape syrup level, specific gravity represents the entry of air bubbles in the batter during mixing and the maintenance of the bubbles in the batter during storage and baking, lower specific gravity of cake batterreflects higher volume of the cakes. The results of texture analysis indicated that grape syrup-added cakes were softer than control sample, one reason for reducing the hardness is that when sucrose replace with grape syrup (that is mainly composed of glucose and fructose), the cake moisture content will increases and as a result caused the reduction of the cake hardness. Evaluation of color parameters showed that L values of cakes decreased and a value increased with addition of natural sweetener (Samples got darker). Sensory evaluation results showed that the cake formulation with 40% grape syrup obtained the highest score by panelists in terms of mouth-feel, wetness, and overall acceptability. It can be concluded that grape syrup could beused as a natural replacer for sugar in preparation of bakery products although further studies are necessary in order to gain appropriate formulation
Forough Zarenejad; Seyed Hadi Peighambardoust; Sodeif Azadmard Damirchi
Abstract
Wheat germ is a by-product of milling industry rich in fiber, tocopherol, unsaturated fatty acids, polyphenol, minerals and protein. In this study, effect of adding raw and stabilized wheat germ on the characteristics of cake batter such as specific gravity, viscosity and cake properties such as volume, ...
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Wheat germ is a by-product of milling industry rich in fiber, tocopherol, unsaturated fatty acids, polyphenol, minerals and protein. In this study, effect of adding raw and stabilized wheat germ on the characteristics of cake batter such as specific gravity, viscosity and cake properties such as volume, apparent density, solid density, porosity, water activity, moisture and firmness was studied. Raw wheat germ was stabilized by steaming for 15 min and subsequent drying at 80 °C for 20 min. It was then ground and added to cake formulation at levels of 5, 10, 15 and 20 % (on flour wet basis). Results showed that adding wheat germ changed the characteristics of cake batter. With increasing amount of raw and stabilized wheat germ, specific gravity and viscosity of cake batter increased and reduced, respectively. Important difference was observed in the physical characteristics between wheat germ enriched and control cakes. Increasing wheat germ in cake formulation decreased cake volume and porosity, while apparent and solid densities were increased. Investigation of moisture content and firmness, in several days of storage, showed that the cakes enriched with raw germ had the higher moisture content than those enriched with stabilized germ. Cakes enriched with stabilized wheat germ had the highest firmness. Incorporation of stabilized wheat germ by controlling its detrimental effects relating to lipase activity which leads to fat rancidity, could favor production of a functional cake with improved nutritional properties.
