Food Technology
Farzaneh Esmaeili; Mahnaz Hashemiravan; Mohammad Reza Eshaghi; Hassan Gandomi
Abstract
[1]Introduction: Nowadays, there is a great tendency to consume functional foods, with special medicinal and extranutritional value in addition to basic nutritional properties. Foods containing probiotics and prebiotic compounds are classified in this category. Inulin is a water soluble storage polysaccharide ...
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[1]Introduction: Nowadays, there is a great tendency to consume functional foods, with special medicinal and extranutritional value in addition to basic nutritional properties. Foods containing probiotics and prebiotic compounds are classified in this category. Inulin is a water soluble storage polysaccharide and belongs to a group of non-digestible carbohydrates called fructans. Inulin is naturally present in some flowering plant species such as chicory and burdock root. The amount of inulin in these plants is in the range of 1 to 20% of the weight of the fresh plant. Pharmacological studies report that Burdock root contains significant amounts of the inulin as a prebiotic compounds, also exhibits a wide range of biological activities, specifically antioxidative, anti-inflammatory, and free radical scavenging activities. The aim of this study was to encapsulate the aqueous extract of burdock root and use it in a probiotic drink based on orange-carrot juice. Material and Method: The Burdock roots were obtained from the local medical plant market, Tehran, Iran. Orange and carrot juice were purchased from Nooshin and Tandis (Food Company, Tehran, Iran) respectively. Maltodextrin and gum Arabic were prepared from Merck, Germany. First, the plant roots were dried to 5.2% moisture and then its aqueous extract was extracted with the help of ultrasonication. Then burdock roots extracts were encapsulated by spray drying (microencapsulation) and freeze drying (nanocapsulation) using maltodextrin and gum Arabic as wall coating agents. Capsule properties including encapsulation efficiency, particle size distribution, moisture, density, structural properties, TPC and antioxidant were determined. Then the encapsulated extracts (at levels of 0.5 and 1%) and free extract were used in the formulation of probiotic orange-carrot juice and its effect on the survival of probiotic bacteria as well as physicochemical and sensory properties of the final product during 30 days in refrigerator (4±0.5 °C) were investigated. All experiments were carried out based on complete randomized design and the results represent the mean of at least three replicates. The data obtained were analyzed by the analysis of variance (ANOVA) using Minitab 16.0 statistical software. Significant differences between means were determined by Duncan’s multiple range test at a probability levels of P≤0.05. Results and Discussion: The results of encapsulation phase showed that Nanocapsules had higher efficiency and phenolic compounds content than microcapsules. The highest level of efficiency (92.75%) and phenolic compounds (0.385 mg GAE/g) and the smallest capsule particle size (14.33±0.22 µm) were observed in Nanocapsules prepared with gum Arabic. The SEM images showed that the produced capsules in terms of microstructure, had flaky/glassy and angular surfaces and did not have a regular shape. By adding different forms of the extract (free/micro/Nano) to the orange-carrot juice, it was found that its characteristics including viability of probiotics, formalin index, turbidity, viscosity and antioxidant activity were significantly enhanced during cold storage compared to the control (p<0.05). During refrigeration, turbidity, acidity and IC50 increased in all treatments, especially in the control sample, while other characteristics (including the viability of probiotic bacteria), showed a decreasing trend. Addition of different forms of burdock root extract did not have an adverse effect on the flavor and odor of the samples, so that, all treatments were acceptable. Therefore, based on the results of this study, it can be stated that encapsulated burdock root extracts, especially in the form of nanocapsulation, can be used to increase the viability of probiotics and enhancement the antioxidant activity of functional foods
Food Technology
Elham Mobini; Leila Nateghi; Mohammad Reza Eshaghi
Abstract
Materials and Methods: To compare physicochemical (pH, humidity, brix and water activity), texture properties (adhesiveness, cohesiveness, springiness, gumminess, chewiness, hardness and deformation of hardness), color indices (L*, a* and b*) and sensory (taste, odor, color, texture and overall acceptance) ...
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Materials and Methods: To compare physicochemical (pH, humidity, brix and water activity), texture properties (adhesiveness, cohesiveness, springiness, gumminess, chewiness, hardness and deformation of hardness), color indices (L*, a* and b*) and sensory (taste, odor, color, texture and overall acceptance) properties of pastille obtained from fish gelatin. The experiments were performed in a completely randomized design. In this study, 5 treatments with three repetitions were examined. In order to compare the means, Duncan's one-way analysis of variance was used at the 95% confidence level using Minitab software version 16. Results and Discussion: According to the results of gel formation temperature, gel melting temperature and gel melting time of fish gelatin were lower than commercial gelatin but gel formation time in fish gelatin was higher than commercial gelatin. Also, the extraction efficiency of gelatin from Kilka fish was 9.204%. Effect of different percentages of extracted fish gelatin on pH, moisture, brix, water activity, color indices (L*, a* and b*), texture properties (adhesiveness, cohesiveness, springiness and gumminess) and sensory evaluation (taste, odor, color, texture and overall acceptance) was significant (p>0.05). The results showed that by increasing the replacement of different percentages of fish gelatin, pH, Brix, L*, all textural histological and sensory evaluation factors decreased and moisture content, water activity and colors a* and b* increased. Differences in pH of gelatins may be due to the type and strength of acid used during the extraction process. Also, due to the replacement of fish with skin and bones in acid and due to having more minerals in the bones than fish meat, more acidic treatment is needed. Therefore, the difference in pH of fish gelatin and cow gelatin can be different depending on the extraction conditions and the type of fish. Hydrochlorothiazine gelatin is a protein that, at temperatures above 35 to 45 degrees Celsius, has a complex structure that dissolves in water and increases brix. The results showed that the amount of water activity of samples containing fish gelatin was higher than commercial gelatin, which could be due to the higher moisture content of gelatin extracted in fish and the extraction conditions and its use in the production of pastilles. The presence of Kilka fish gelatin in the pastel formulation caused the samples to get darken or turn red due to the increase in a * and b * indicators. The reason for the discoloration of the specimens can be due to the presence of carotenoids in the tissues of fish (tonagazantine (yellow), lutein (yellowish-green), beta-carotene (orange), duragazantine (yellow), zaxanthin (orange-yellow), Contagantine (red-orange), astaxanthin (red), and taragzantine (yellow)). The reason for the instability and poor rheological properties of fish gelatin compared to commercial gelatin is mainly related to the low number of proline-rich regions and low amounts of immunoassides (hydroxyproline and proline) in the collagen and gelatin molecules of fish compared to warm-blooded animals. The content of proline and hydroxyproline amino acids in fish gelatin is lower than in animal gelatin, such as pork, which exhibits better viscoelasticity. Therefore, they show weaker viscoelastic properties than commercial gelatin. In addition, fish gelatin contains less alanine, and this amino acid is commonly found in areas rich in proline and hydroxyproline. Most of these amino acids in commercial gelatin are one of the main reasons for their higher viscosity. The release of flavor is significantly related to the texture of the gel, and gelatin gels, due to the harder texture, release less flavor, which in turn reduces the overall acceptance score in samples containing high amounts of gelatin. Watman's filter paper, vacuum pump, ion exchange resin are commonly used to remove odors and derivatives, and vacuum evaporators are used to eliminate the unpleasant odor of fish in order to eliminate odors, dyes, unfavorable fish flavors, and unstressed collagen. However, the smell and taste of the remaining fish of the above methods reduce the sensory evaluation scores in treatments containing fish gelatin, and the main reason for the decrease in sensory evaluation scores in fish gelatins is the persistence of fish odor and taste in gelatin.T2 treatment (containing 50% fish gelatin + 50% commercial gelatin) was selected as superior treatment because of its proximity to control, physicochemical, rheological and sensory evaluation. In general, the results showed that using different percentages of gelatin extracted from Kilka fish had no adverse effect on the physicochemical and rheological properties of pastille and only sensory evaluation reduced due to the taste and odor of Kilka fish. The taste of pastilles produced covered the poor sensory evaluation properties of fish pastels produced from gelatin and used in industrial gelatin production.
Nafiseh Ravatab; Simin Asadollahi; Mohammad Reza Eshaghi
Abstract
Introduction: Chocolate is a complete and correct process of mixing one or more primary ingredients with the cocoa beans. These raw materials include the edible sweeteners or sugar, dry milk powder, edible essential oil and flavors as well as plant kernels. Despite high levels of fat and sugar, chocolate, ...
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Introduction: Chocolate is a complete and correct process of mixing one or more primary ingredients with the cocoa beans. These raw materials include the edible sweeteners or sugar, dry milk powder, edible essential oil and flavors as well as plant kernels. Despite high levels of fat and sugar, chocolate, has a significant contribution to human nutrition through the supply of antioxidants and polyphenols. It also has the beneficial minerals, especially potassium, magnesium, copper and iron. Milk chocolate is a complex rheological system that includes the solid phase (cocoa powder, sugar powder and no-fat dry milk powder) released in the continuous phase of cocoa butter. As mentioned, the chocolate contains three essential ingredients in foods, namely, protein, carbohydrate and fat, along with essential minerals that considering its physicochemical properties, the property of functionality can be activated in it by adding certain materials. The first member of omega-3 family is the alpha-linolenic acid that is not produced in the human body, hence it is called essential fatty acid and plays a very important role in many physiological responses of the human body and is considered as a necessity in the diet. The plant resources are healthier, cheaper, and more accessible. The highest amount of fatty acids, α-linolenic acid (short omega-3 chain), was found in plants. Among the plants, flaxseed has the highest fatty acid content (about 50%). Considering the above-mentioned cases, the possibility of producing the functional milk chocolate containing omega-3 fatty acid by this plant resource was investigated.
Materials and Methods: The treatments included control, L10, L20, L30 and L40 with the amounts of 0, 10, 20, 30 and 40% of flaxseed powder replacing butter, cocoa powder, dry milk and sugar. The experiments conducted included the study of physicochemical (sugar, fat, acidity, moisture content, peroxide, ash, particle size, texture and omega-3 levels) and sensory properties. In order to analyze the data of the research, a factorial experiment was used in a completely randomized design and the mean comparison was conducted by Duncan's multiple range test at the probability level of α =5%.
Results & discussion:The results obtained by studying the effect of adding flaxseed powder on the physicochemical properties, color, texture and sensory properties of functional milk chocolate showed that the addition of this material does not have a negative effect on the chemical properties of any treatment. The biggest concern was the oxidation of the oil in the flaxseed powder, which was solved with keeping conditions at 4 ° C and in none of the treatments the amount of peroxide did not increase more than the standard of chocolate (2%). On the other hand, the moisture content of the chocolate remained at the standard level due to the proper packaging and dry storage. Chocolate produced had a bitter taste in L30 and L40 treatments, despite having a good amount of sugar and dry milk powder, due to the relatively bitter taste of flaxseed oil and powder, but this bitterness was not so bad and unpleasant in L10 treatment. Chocolate acidity was not changed undesirably by adding flaxseed powder and replacing some of its oil with cocoa butter. Since the particle size of the flaxseed powder was more than that of cocoa powder and sugar, it reduced the volumetric surface, and fewer chemical bonds was formed between the hydrophilic and hydrophobic surfaces, resulting in less storage time of product at room temperature. Of course, this problem was less significant in L10 treatment, but in L30 and L40 treatments an inappropriate texture were found. The amount of omega-3 residues was zero in L10 and L20 treatments and was not detected by chromatography device, which indicated an inadequate ratio of antioxidant and flaxseed powder. However, since the maximum allowed antioxidants were used in chocolate, more amount of flaxseed should be used, so that as L30 and L40 treatment this fatty acid remains in the chocolate and does not oxidize. Also, by increasing the amount of flaxseed powder in treatments, viscosity also increased, due to the large size of particles and the lack of adequate bonding between hydrophilic and hydrophobic parts. Of course, this indicator was so high in L40 treatment that a problem was even created in molding. The texture analysis behavior of the chocolate indicated that the chocolate texture was loose in L40 treatment so that it lacked the value of production. The texture of this treatment was so loose that it became doughy at ambient temperature. In terms of sensory properties, a significant difference was found between the treatments and the control sample, indicating a decrease in the quality of chocolate produced. Overall, L40 treatment score was low due to so weak and doughy texture, inappropriate and bitter taste, the relatively dark color and the presence of many large pieces of flaxseed powder on chocolate. Therefore, its production does not seem logical, despite the proper amount of omega-3. L30 treatment had more desirable condition, but here, the texture was relatively loose too due to the presence of coarser flaxseeds. Of course, covering the bitter taste of flaxseed with sugar and dry milk powder and vanilla improved the opinion of the experts and increased their scores. It is noteworthy that the appearance and color of the product had better quality than L40 treatment. Regarding L10 and L20 treatments, although the scores of experts were better and they had better texture, color and flavor than two L30 and L40 treatments, but they did not have justifiable production due to the lack of remaining omega-3 in them that was the main purpose of this study. Totally, considering all properties, L30 treatment was introduced as the best treatment.
Leila Khajehvandi; Majid Javanmard; Mohammad Reza Eshaghi
Abstract
Introduction: Studies in recent years have led to the emergence of a new concept in the packaging industry namely “Active packaging”. Contrary to popular packaging that needs to be completely neutral and ineffective, in different kinds of active packaging, there is an interaction with food ...
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Introduction: Studies in recent years have led to the emergence of a new concept in the packaging industry namely “Active packaging”. Contrary to popular packaging that needs to be completely neutral and ineffective, in different kinds of active packaging, there is an interaction with food or environment, and has an active role in food materials maintenance (Brody et al, 2008). Nowadays, various kinds of polymeric materials and their different characteristics and forms has resulted in easy design and production of packaging based on special requirements of a food product (Lopez-rubio et al, 2004). Polyethylene and polypropylene along with cardboard boxes are used for packing butter (Milts, 1988). It has been proved that Alpha-Tocopherol maintains its stability in the processing conditions and low aw also maintain its stability, alpha – Tocopherol has desirable migration characteristics and excellent solubility in polyolephines. use of alpha- Tocopherol is more affordable compared to other antioxidants (Lee, 2005; Wessling et al, 1998).The aim of this study was to investigate the effect of alpha-tocopherol coating on the surface of polymer films in preventing the oxidation of lipid in butter.Materials and Methods:MaterialsDL-alpha-tocopherol acetate, low density polyethylene film(LDPE) , biaxial oriented polypropylene film (BOPP), traditional-lactic butter with salt made from cow's milk .MethodsPreparation of films: In this stage, first alpha-tocopherol was prepared with three concentrations of %0.1, %0.15and %0.2, and %70 ethanol was used as solvent. In the next step, low density polyethylene and polypropylene films were prepared in enough dimensions and numbers, and were washed and sterilized by %70 ethanol. Then, different concentrations of alpha-tocopherol (%0.1, %0.15,%0.2) were separately covered on a sufficient number of films via spraying (under identical conditions).to complete coverage of the films surface, spraying alpha-tocopherol was performed 3 times. after drying, films were kept in dark place (Pereira et al, 2011).Packaging and storage of butter: At this stage, butter pieces weighing 45 grams covered with LDPE and BOPP films with three different concentrations of alpha-tocopherol (%0.1,%0.15,%0.2) were packed. To prepare the control sample, butter was packed with alpha-tocopherol lacked films. The experiments of determining the amount of peroxide and acidity, and Sensory evaluation test was conducted on a sample of butter before packaging, and were repeated in tenth, twentieth ,and thirtieth days.Determining the amount of alpha-tocopherol remained on the films : At this stage, in order to determine the amount of alpha-tocopherol remaining on the films, weight difference of films before and after spraying alpha-tocopherol, and drying them on the films was measured. The amount was calculated by mg/cm2 stated (Contini et al, 2012).Measurement of alpha-tocopherol migration to ethanol: The total amount of alpha-tocopherol migrate from the films into the similar lipid matter(%95 ethanol)were calculated by the colorimetric method using a standard alpha-control solution and drawing the calibration curve(Corrales et al, 2009).The Sensory evaluation test: To evaluate the sensory properties including taste, color, smell and public acceptance, five-point hedonic test was used(Tafreshi et al, 2013).Methods and tools for data analysis: All tests were repeated three times. For data analysis, a factorial experiment in a completely randomized design was used. Alpha-tocopherol concentration, time and type of film were the main factors. Duncan multiple range test was used to assess the differences between means in the confidence level of %5.For all statistical analysis, MSTAT-C software version 14 was used.Results and Discussion: Findings from surveying the migration process into 95% ethanol solution, indicates that alpha-tocopherol were remained on the surface of polymeric films (LDPE &BOPP) after drying, and migrated from the surface of films into ethanol %95. With the increase of time and concentration of alpha-tocopherol, migration from the surface of films into ethanol increased (p
