Food Chemistry
Samar Sahraee; Jafar Milani
Abstract
Protein films have gained significant attention in the development of sustainable packaging materials due to their exceptional properties and versatility. These films offer superior gas barrier properties, specific mechanical characteristics, and enhanced intermolecular connection capabilities compared ...
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Protein films have gained significant attention in the development of sustainable packaging materials due to their exceptional properties and versatility. These films offer superior gas barrier properties, specific mechanical characteristics, and enhanced intermolecular connection capabilities compared to other biopolymers. Researchers are exploring innovative methods to enhance the film-forming properties of proteins, improve their mechanical strength, and optimize their gas barrier performance. Various protein sources, such as gelatin, whey protein, soy protein, corn zein, wheat gluten, and casein, are being investigated for film fabrication. Techniques to modify protein films, including the incorporation of additives, crosslinking agents, and nanomaterials, are being explored to enhance their properties. The development of protein-based composite films, by blending proteins with other biopolymers or synthetic materials, is also being explored to achieve improved performance and functionality. Advancements in processing technologies, such as film casting, extrusion, and electrospinning, enable precise control over the thickness, morphology, and structural properties of protein films. These films not only offer enhanced barrier properties but also possess biodegradability and renewable characteristics, aligning with the increasing demand for eco-friendly packaging solutions. The preparation and improvement of protein films hold significant potential for revolutionizing the packaging industry and contributing to a greener and more environmentally friendly future. This review provides an overview of current research and advancements in the field, addressing various protein sources, film modification techniques, processing methods, challenges, and future prospects.
Food Chemistry
Iysan Izanloo; Alireza Sadeghi Mahoonak
Abstract
Introduction Free radicals originate from oxidation reactions decrease food quality and also promote incidence of various diseases such as cancer. In this regard, the use of natural compounds with antioxidant properties, such as bioactive peptides, is of interest to many researchers. Food-derived ...
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Introduction Free radicals originate from oxidation reactions decrease food quality and also promote incidence of various diseases such as cancer. In this regard, the use of natural compounds with antioxidant properties, such as bioactive peptides, is of interest to many researchers. Food-derived bioactive peptides, can play an important role in the oxidative systems. Ultrasound, as a cheap and green technology, is widely used to extract proteins and antioxidant compounds. Ultrasound pretreatment before enzymatic hydrolysis can open the protein structure and increase the intensity of proteolysis by increasing the exposure of peptide bonds prone to enzymatic hydrolysis; which increases the production efficiency of bioactive peptides. Ultrasound treatment changes the three-dimensional structure of proteins. Therefore, a combination of pretreatment with ultrasound and sequential enzymatic hydrolysis can be a promising way to modify the function of proteins. Materials and Methods In this research the effect of hydrolysis time and ultrasonic pretreatment on enzymatic hydrolysis of edible mushroom protein by pancreatic enzyme to produce peptides with high antioxidant capacity was evaluated. First edible mushroom was turned into powder and then, in order to optimize the production of hydrolyzed proteins with maximum antioxidant activity, the hydrolysis was performed 30, 60, 90, 120, 150, 180 and 210 minutes with a ratio of enzyme to substrate of 1% (based on the result of previous research) and at 40°C in four conditions (1- without ultrasound pre-treatment, 2- with ultrasound pre-treatment with 40% power, 3- with ultrasound pre-treatment with 70% power and 4- with ultrasound pre-treatment with 100% power) by ultrasound probe in 5 minutes before adding the enzyme. In the next step, the antioxidant capacity of hydrolyzed proteins was measured at different times by DPPH free radical scavenging activity, iron ion reduction power, iron ion chelation and total antioxidant capacity. Results The results showed that the highest DPPH free radical scavenging activity in untreated and treated samples with 40, 70 and 100% ultrasound power were 69.1, 77.45, 79.07 and 80.27, respectively. In most of the hydrolysis times, DPPH free radical scavenging activity in ultrasound treatment with 100% power was higher than the samples treated with 40 and 70% power. The highest total antioxidant capacity in untreated and treated samples with 40, 70 and 100% ultrasound power were 0.871, 1.025, 1.05 and 1.2 (absorption at 695 nm), respectively. In most of the hydrolysis times, the total antioxidant capacity in the samples treated with ultrasound with 100% power was higher than the samples treated with 40 and 70% power. The results showed that the highest reducing power of Fe3+ in untreated and treated samples with 40, 70 and 100% ultrasound power were 2.03, 2.40, 2.44 and 2.51(absorption at 700 nm), respectively. The highest iron ion chelation power in untreated and treated samples with 40, 70 and 100% ultrasound power were 25.22, 30.40, 26.52 and 41.10%, respectively. By increasing the ultrasound power in most of the hydrolysis times, the chelating power of iron ions in the ultrasound treatment with 100% power was higher than the samples pretreated with 40 and 70% power. The results showed that samples pretreated with 100% power ultrasound have the highest antioxidant properties compared to samples without pretreatment and pretreated with 40% and 70% ultrasound power. Based on the results, using ultrasound treatment with 100% power and during hydrolysis time of 60 minutes, a product with high antioxidant capacity was obtained and selected as a suitable treatment. Conclusion The ultrasonic mechanism is attributed to its thermal effects, cavitation and mechanical efficiency, so that it can increase the mass transfer and increase the contact between the substrate and the enzyme or change the spatial structure of the substrate. The results showed that samples pretreated with ultrasound with 100% power have the highest antioxidant properties compared to samples without pretreatment and pretreated with 40 and 70% power. Therefore, the use of high-power ultrasonic pretreatment shortens the hydrolysis time to achieve peptides with higher antioxidant capacity and thus increases the efficiency of enzymatic hydrolysis.
Mahya Ouraji; Mazdak Alimi; Ali Motamedzadegan; Shirin Shokoohi
Abstract
Introduction: In recent years, legumes have been highly considered as a good source of protein, fibers, minerals and other bioactive compounds in order to develop novel foods with improved nutritional properties. There is some evidence that legume consumption reduces the risk of diabetes, cardiovascular ...
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Introduction: In recent years, legumes have been highly considered as a good source of protein, fibers, minerals and other bioactive compounds in order to develop novel foods with improved nutritional properties. There is some evidence that legume consumption reduces the risk of diabetes, cardiovascular disease and some cancers. Vicia faba has about twice protein content as cereals and can be a good alternative to meat and protein-rich ingredients. It should also be noted that the amount of insoluble fiber is higher than soluble fibers in legume. Vicia faba belongs to the Fabaceae family .Vicia faba contains high protein (21-41% dry content of the bean), carbohydrates (51-68% dry content of the bean), fiber (5-5.8%), B-vitamins and minerals. Recently, the protein function of Vicia faba, especially its protein isolate, has been studied on a laboratory scale for use in food products, due to its good ability in hydration, solubility, emulsification, viscosity, and foam and gel formation. Research has also shown that the protein in Vicia faba has better ability to emulsify water and oil and foaming capacity and foam stability compared to bean and pea flour. The structural and functional properties of the protein isolates and concentrates of legumes such as Vicia faba are strongly influenced by their preparation, extraction and drying methods. One of the ways to improve extraction and optimization of protein properties can be ultrasound and an enzymatic controlled hydrolysis. Due to the importance of dietary fiber, various methods have been developed for their decomposition, many of which are very precise and special, some of which have high-purity enzymes and selectively release oligosaccharides and polysaccharides containing dietary fiber. In this study, the possibility of using ultrasound and limited enzymatic hydrolysis in order to produce value added product and increase the extraction efficiency and improve the functional properties of protein and fiber of Vicia faba, were evaluated. Materials and Methods: In this study, ultrasound and enzymatic hydrolysis were used to optimize extraction and modify physicochemical properties of protein and fiber of VaciaFaba. The proteins were affected by ultrasound at 200, 300 and 400 W for 15, 25 and 35 minutes, and the Alcalase enzyme 2.4 LFG at 0.15, 0.3 and 0.45% doses were extracted at 15, 25 and 35 minutes and the design of the treatments was done by Designer Express software. Solubility, oil absorption capacity, emulsification and zeta potential of protein samples were measured. Vicia faba fiber extraction under alkaline conditions was obtained from solutions of 0.0012, 0.012 and 0.12% sodium hydroxide until reaching pH 12, 11 and 10 and Termamy 2x enzyme was used for enzyme hydrolysis. Water retention capacity and rheological properties of Vicia Faba fiber samples were investigated. Results and Discussion: The results showed that the use of ultrasound and enzymatic hydrolysis had a positive effect on solubility, oil absorption capacity and emulsion properties of the protein samples. Zeta potential was also negative for all treatments, which indicates that the Vicia faba protein treatment solution contains more negative amino acids than positive-loaded amino acids. Among the fiber samples of the ViciaFaba, a fiber sample with a pH of 10 had the highest water retention capacity and G-level than the other two samples, indicating a more solid and elastic quality. Also, in all fiber samples, increasing cutting speed reduced the viscosity and the samples showed a dilution action with cutting or pseudoplastic.
Haidar Naseri; Eisa Hazbavi; Faizollah Shahbazi
Abstract
Introduction: Among the foods consumed on a daily basis, milk has the most appropriate and balanced ingredients, that is the reason milk called whole food. Milk is the only known substance in nature that can provide the human body with complete and balanced nutrition. Recombined milk is a milk replacement ...
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Introduction: Among the foods consumed on a daily basis, milk has the most appropriate and balanced ingredients, that is the reason milk called whole food. Milk is the only known substance in nature that can provide the human body with complete and balanced nutrition. Recombined milk is a milk replacement product. Recombined milk components are more easily adjustable than milk components. The electrical conductivity is referred to as conductivity of specific material against the electric current, which is expressed in micro Siemens units per cm (mS/cm). Using electrical conductivity, valuable information is available about the quality of different materials, including food. In addition, by this method, as a simple and practical tool, the quality of many foods can be controlled. The aim of this study was to investigate the electrical conductivity of recombined milk affected by temperature, protein percentage, and lactose content. Materials and methods: In order to investigate the effect of protein percentage (1, 2 and 3%) and percentage of lactose or sugar content (4, 6 and 8%) on the electrical conductivity of milk, pure dry milk powder without dietary supplementation was used. Lactose powder was used to increase the lactose content of dry milk powder. Sodium caseinate was used to increase the protein content of dry milk powder. Distilled water was used to increase the volume of samples. Total experiments were carried out at three temperature levels (50, 55 and 60 ºC). Data analysis was also done using SPSS 16 software. Results and discussion: The results showed that temperature, protein percentage, and lactose percentage had a significant effect on the electrical conductivity of recombined milk. The electrical conductivity of the recombined milk ranged from 2.31 to 5.7 mS/cm at 50°C, 8% lactose, 1% protein, and 60°C, 4% lactose, 3% protein, respectively. The greatest and least effect on the electrical conductivity of recombined milk was related to the effect of protein percentage and lactose percentage, respectively. By increasing the temperature, the electrical conductivity of the reconstituted milk has increased significantly. The greatest changes in electrical conductivity (16%) of recombined milk occurred by the influence of temperature factor in protein 1% and lactose 4% and its value ranged from 2.44 to 2.83 mS/cm. In addition, the lowest changes in electrical conductivity (6%) of recombined milk were obtained by the temperature factor of 3% protein and 8% lactose, and it was increased from 4.68 to 4.95 mS/cm. By increasing protein content, the electrical conductivity of recombined milk has increased significantly. The most changes in electrical conductivity (107%) of recombined milk occurred by the influence of protein percentage at 55 °C and 6% lactose and its value ranged from 2.42 to 5.6 mS/cm. In addition, the lowest changes in the electrical conductivity (100%) of reconstituted milk occurred by the influence of protein percentage at 55 °C and 4% lactose, and its content increased from 2.5 to 5 mS/cm 5. These results indicate that the protein percentage factor has the most effect on the electrical conductivity of recombined milk (compared to two temperature factors and lactose percentage). By increasing lactose content, the electrical conductivity of recombined milk has decreased significantly. The greatest changes in electrical conductivity (13%) of recombined milk occurred by the influence of lactose percentage at 60 °C and protein 3% and its content decreased from 5.7 to 4.95 mS/cm. Also, the smallest changes in electrical conductivity (1.5%) of reconstituted milk occurred by the influence of lactose percentage at 55 °C and 2% protein, and its content decreased from 5.55 to 4.48 mS/cm. The maximum and minimum amount of electrical conductivity of reconstituted milk was 5.7 mS/cm at 60°C, 4% lactose and 3% protein, and 2.31 mS/cm at 50°C, 8% lactose and 1% protein, respectively.
Fatemeh Rahmati; Arash Koocheki; Mehdi Varidi; Rassoul Kadkhodaee
Abstract
Introduction: Proteins are food ingredients with critical functional properties and participation in developing food products. So far, functional properties of several plant proteins such as pea, chickpea and lentil, groundnut, beach pea and bayberry have been investigated. Nowadays, there is an increasing ...
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Introduction: Proteins are food ingredients with critical functional properties and participation in developing food products. So far, functional properties of several plant proteins such as pea, chickpea and lentil, groundnut, beach pea and bayberry have been investigated. Nowadays, there is an increasing demand for plant proteins because they are available and inexpensive. Legume proteins are important plant protein sources. However, except for soy, due to the inadequate information about their structural and functional properties, they do not have appropriate application as functional ingredients in food products. Beans are a great source of nutrients such as protein, carbohydrate, dietary fiber, minerals and vitamins. Based on the several research reports, different dry beans have 15-25% protein and they are the second group of legume seeds, after soy, cultivated throughout the world. As mentioned earlier, insufficient information about structure of legume proteins is the main reason why they are unexploited in food industry. Therefore, the goal of this research was to evaluate the functional properties of proteins from three types of common bean (Speckled Sugar, Red Mexican and Great Northern bean). We also have attempted to evaluate the structure-function relation of these three sources of bean proteins because it is known that there is a direct relation between chemical conformation and the function of a protein which must be considered in food processing. Materials and methods: Protein of three types of common bean (Speckled Sugar, Red Mexican, and Great Northern) was extracted (pH 9, water flour 10:1). Afterwards, their physicochemical (including protein electrophoresis pattern, solubility, hydrophobicity), and functional properties (including emulsifying capacity, heat stability, gelation and foaming capacity) were evaluated to understand how bean protein structure influences its structure. Electrophoresis pattern was obtained based on 2 dimensions (pH and molecular weight). Protein solubility was evaluated by biuret method at pH range 3-9. ANS (8-anilino-1-naphthalenesulfonic acid) was used to measure surface hydrophobicity (pH 3-7).Emulsion samples (1% protein, 25% sunflower oil, pH 3-7) were produced, then emulsion capacity and emulsion heat stability (80°C for 30 min) were evaluated. Gelation of proteins was evaluated at protein concentration of 4-12% at different pH values (3-7). Foaming capacity (%) was measured as the difference between volume after and before whipping. Foam stability (%) was recorded during 90 minutes. Results and Discussion: Results showed that all proteins were rich in Phaseolin. In fact, this fraction was the major building fraction of all three bean proteins. Evaluation of solubility indicated that isoelectric point of three proteins was located at acidic pH range (pH 4.5). Results confirmed an indirect relation between protein solubility and hydrophobicity. All three protein isolates, similar to the other legumes protein, were more soluble at alkaline pH, while the highest surface hydrophobicity was observed at pH 3. Generally, Speckled Sugar bean protein had the most solubility, while Great Northern bean protein showed the highest surface hydrophobicity. Among three bean protein isolates, Speckled Sugar bean protein performed better as an emulsifier, whereas Great Northern bean protein formed gel at the lowest concentration (6% at pHs 3 and 7). In addition, foaming was higher at acidic pH (pH 3). Therefore, it was concluded that emulsifying capacity is mostly influenced by protein solubility, while gelation and foaming properties are affected by protein hydrophobicity. As the main consequence, the results achieved in this research confirmed that there is a direct relation between structure and the function of a protein. In fact, special structural properties are responsible for special functions.
Saeed Mirarab Razi; Mohebbat Mohebbi; Mohammad Hossein Hadad Khodaparast; Arash Koocheki
Abstract
Introduction: Proteins are widely used in food industry because it has functional properties such as formation and stabilization of foam systems. These molecules had surface-active properties. They rapidly adsorb at interface during the foaming processes and form a film around gas bubbles. The bulk properties ...
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Introduction: Proteins are widely used in food industry because it has functional properties such as formation and stabilization of foam systems. These molecules had surface-active properties. They rapidly adsorb at interface during the foaming processes and form a film around gas bubbles. The bulk properties has important role in the stabilization foam system. It has been shown that protein adsorption is influenced by molecular properties, such as size, shape, surface hydrophobicity, conformation, and charge and conditions in the bulk solution, such as bulk concentration, pH and ionic strength. The foaming properties depend on many intrinsic factors (size, structure of protein, hydrophobicity, surface potential, charge, etc.); and environmental and processing factors (protein concentration, pH, temperature, addition of other ingredients, etc.) Foams are colloidal systems in which gas phase dispersed in an aqueous continuous phase. Foaming operation is usually devoted to produce lighter products, modify the appearance and the texture of food products, therefore, it be used to production new products adapted to consumer choice and needs, using air as a zero-cost component. Microstructure has fundamental role in foam properties. At foam based products, bubble size is of most importance at the foam properties, because it influences on texture, the mouth-feel and the stability of the aerated product. Many food products have aerated structure. In these foods, the gas phases, forms small bubbles that modify microstructure and mouth feel properties of product. Aerated desserts have shown a great market potential, which is dependent on consumer behavior, interested in lighter and healthier products. Food products based on foam structure such as chocolate mousse have good marketing; therefore deep knowledge about their properties is important. Mousse is an aerated dessert with stabilized foamy structure which little attention has been paid to industrial production. Although, the most popular mousse flavor is chocolate, orange, lemon and strawberry have good marketability.Materials and method: This study follows two important objectives; first, the effect of different amount of gelatin concentration and sodium caseinate on rheological, physical and sensory properties of chocolate mousse is investigated. Then, the relationship this parameters was discussed on the basis of laboratory results using PCA method. Chocolate mousse was include of, Gelatin(Bangladesh, type B, bloom 160-180), Cacao powder(Cargill Co., Netherlands), Whipped cream(Mahrang sahar shargh CO., Iran 27% fat), Sugar(Fariman, Iran) and Sodium caseinate (Milad, Iran). Chocolate mousse samples were prepared with different amount of gelatin (1, 2 and 3 gr) and sodium caseinate (1, 2 and 3 gr) concentrations. Gelatin was first dissolved in hot water. Next, cacao powder and sugar were stirred in hot water and added to whipped cream agitated by Gosonic home mixer with speed 5400 RPM for 3 minutes. Then, Sodium caseinate was mixed in distilled water for 2 minutes and added to mixture prepared. Finally, mousse was placed in refrigerator after stirring with gelatin solution. The samples were stored in a refrigerator for 24 hours.Results and Discussion: In this work, physical, sensorial and rheological properties of chocolate mousse were investigated. Rheological measurements were carried out using a rotational viscometer (Bohlin Model Visco 88, Bohlin Instruments, UK) equipped with a heating circulator (Julabo, Model F12-MCand, Julabo Labortechnik, Germany) and C30 spindle. All the experiments were performed at 25°C±0.2. A pre shearing of 10-15 s at 14.1 s was applied to all samples. Sample flow was measured by registering the shear stress/ shear rate data at an increasing trend from 14.1 to 300 s. To describe the time independent flow behavior, the experimental data (shear stress-shear rate) were fitted by Herschel- Bulkley, Bingham, power law, and Casson models. Sensorial properties were tested at the same optical condition and environmental temperature. Chocolate mousses were evaluated using hedonic analysis procedures by a sensory panel of ten assessors, who had been selected and trained. Sensorial properties were evaluated based on 1 to 9 scores. The gas hold-up was calculated by comparing the density of the aerated chocolate with the gas-free density of solid chocolate. PCA method was used for determination of the relation of sensory attributes and main component.Conclusion: Results showed that chocolate mousse incorporating 2 gr gelatin and 3 gr sodium caseinate had the best sensory properties. According to the R2 (R2>0/99) and RMSE values, it is obvious that the Power-law models can properly describe non-newtonian flow behavior of samples. Behavior index (n) and consistency coefficient (k) were obtained from fitting power-law model. Consistency coefficient was high in the sample containing 3 gr gelatin and 3 gr sodium caseinate. Density values decreased with increase in protein content and decrease in gelatin content. Based on PCA results, total acceptance of samples was severely related to the smoothness, jelly and melting rate attributes.
