Food Engineering
Fateme Mousavi Baygi; Arash Koocheki; Behrooz Ghorani; Mohebbat Mohebbi
Abstract
Introduction Curcumin, as a natural polyphenolic nutraceutical has been shown many health-promoting effects, mainly associated with its chemical structure. In various studies, different properties of this compound, including anti-tumor and anti-cancer activity, reduction of blood and liver cholesterol ...
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Introduction Curcumin, as a natural polyphenolic nutraceutical has been shown many health-promoting effects, mainly associated with its chemical structure. In various studies, different properties of this compound, including anti-tumor and anti-cancer activity, reduction of blood and liver cholesterol levels, increase of immune function, prevention of cardiovascular diseases, prevention of damage to biological membranes against peroxidation and anti-inflammatory properties have been reported. Despite possessing a potential health benefits to humans, the susceptibility of this polyphenol towards environmental conditions and low chemical stability has restricted the direct usage of curcumin into aqueous-based food formulations. The encapsulation of curcumin in liposomes is a potentially effective way to protect them from degradation during passing the digestive system.Materials and MethodsCurcumin (powder, purity greater than 99%, 368.38 g/mol), lecithin, cholesterol (C3045-25G), pancreacin (extracted from porcine pancreas, P7545-25G), bile salts (B8756-10G) and calcium chloride (CaCl2) was obtained from Sigma Aldrich (USA). Consumable ethanol was purchased from Pars Ethanol Company (96%, Iran). Lipase enzyme (extracted from pig pancreas, L8070) and pepsin (activity 3500-3000 NFU/g, P8390) were obtained from Solarabio (China). Potassium chloride, dipotassium hydrogen phosphate (K2HPO4) and alpha-amylase enzyme with a purity of at least 99% were obtained from Merck, Germany, sodium chloride (NaCl), sodium bicarbonate (NaHCO3) and calcium chloride were obtained from Sigma. The effect of lecithin content (0.02- 0.08 g), lecithin cholesterol ratio (0.5- 4), curcumin level (1.5- 6mg) and ultrasound treatment time (1-5 minutes) on production of liposomes containing curcumin was evaluated. The particle size, particle size distribution, zeta potential and efficiency were determined by response surface methodology. Furthermore, physical nature, molecular structure, physical stability at 4ºC and 25ºC and release behavior of curcumin loaded-liposome in mouth, stomach and intestines were explored.Results and Discussion The results showed that all independent variables had a significant effect on liposome particle size and increasing the ratio of lecithin: cholesterol caused more uniform particle size. Lecithin was determined to be the only component affecting the zeta potential of liposome particles, and increasing the ultrasound time increased the efficiency of curcumin encapsulation in liposomes. The optimal point of liposome preparation conditions in the amount of 0.08 g lecithin, 4: 1 the ratio of lecithin: cholesterol, 4.16 mg curcumin and 5 minutes the ultrasound treatment was introduced by Design Expert software. In addition, curcumin was amorphous in optimal liposome spherical particles. Furthermore, the results of TEM showed that the liposomes are in the form of single-layer particles, spherical and without membrane rupture. This makes the bilayered nature of the vesicles clearly visible in this micrograph. The size of the particles obtained from this method was consistent with the data obtained from the dynamic light scattering method. From the results of infrared spectroscopy, it can be seen that curcumin is trapped in the liposome through hydrogen bonding in the double-layered vesicle of the liposome, the phenolic ring of curcumin with the phospholipid head group, as well as the hydrophobic interactions of the aromatic rings with the acyl phospholipid chains. Liposomes were more stable at refrigeration temperature. A very small amount of curcumin was released in the simulated oral phase, which is probably due to the short time and lack of specific enzymes to disrupt the phospholipid bilayers of the liposome. Although the pepsin enzyme is unable to penetrate the liposome membrane, acidic conditions change the angle of the head and tail groups of the lipids and lead to a change in the surface charge of the liposomes. The release of curcumin from liposome vesicles was greatly increased in the intestine. This sudden increase is due to the presence of bile salts as an emulsifying agent that can disrupt the phospholipid membrane and make the membrane more fluid. In addition, pancreatic lipase is adsorbed on the surface of lipids and then hydrolyzes the phospholipid into 2-acyl and 1-acyl lysophospholipids and free fatty acids. The release behavior of curcumin under gastrointestinal conditions was based on the Fick mechanism.
Seyed Amir Oleyaei; Babak Ghanbarzadeh; Ali Akbar Moayedi; Parisa Poursani; Fateme Mousavi Baygi; Mohammad Reza Bakhsh Amin
Abstract
Introduction: Biopolymers are a class of polymer, which are disintegrated by an enzymatic or bio-path and the products disseminated to the surroundings do not induce negative effects. Nowadays, non-degradable polymers are quid pro quo with biodegradable ones particularly in agricultural applications, ...
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Introduction: Biopolymers are a class of polymer, which are disintegrated by an enzymatic or bio-path and the products disseminated to the surroundings do not induce negative effects. Nowadays, non-degradable polymers are quid pro quo with biodegradable ones particularly in agricultural applications, environmental and food industry use. Starch is an example of natural biopolymers, biocompatible, which is completely biodegradable in environment. It has been considered as one of the best candidates for oil based polymer substitution due to its low cost, availability and processbility. The main disadvantages of starch based polymers are their high hydrophilic nature therefore; they have poor mechanical properties and are permeable to water vapor. However, these aspects could be considerably reclaimed by shuffling it with nanodimension materials such as itanium dioxide (TiO2) and Montmorillonite (MMT). The main reason for this improvement in comparison with conventional composites is the large surface area of these nanomaterials which results in high interactions between the nanofillers and starch. The functional behaviors of nanocomposite films have been depended to the compatibility and degree of nanoparticles dispersion in the biopolymer matrix. TiO2 is a 3D nanosphere has been perused widely because it is inexpensive, chemical inert and, has a high refractive index with visible and UV shielding potential. MMT as a 1D, platelet is the most commonly used layered silicates. The investigation of biodegradable films containing two different nanofillers simultaneously has been rarely done. TiO2 and MMT as two different inorganic nanofillers have different physical and chemical structures, so simultaneously use of TiO2 and MMT clearly had a new effect on the nanoparticle distribution and functional properties of starch films. The aim of this study was investigate the synergistic or antagonistic effect of combination of TiO2 nanoparticles and MMT platelets on the functional properties such as surface hydrophobicity, water vapor permeability (WVP), moisture uptake (MU), Water Solubility (WS) and mechanical properties of plasticized starch-MMT-TiO2 nanocomposites.
Materials and methods: 100 ml of potato starch solution with a concentration of 4% (w/v) was prepared by dispersion of starch in distilled water. It was gelatinized at 80 ºC for 15 min. Different amount of TiO2 (0.5, 1 and 2% w/w starch) and MMT (3 and 5% w/w starch) were dissolved in distilled water and added to the gelatinized starch after treatment with ultrasound for 30 min. Glycerol with concentration of 50% (w/w starch) was added to the starch-nanofillers filmogenic solution. Bionanocomposite plasticized starch (PS) films were produced by casting and were dried in an oven at 45 °C for 15 hours. The X-Ray diffraction (XRD) measurements were performed for MMT and TiO2 powder and starch-MMT and –TiO2 nanocomposite films. The methodology of WVP measurements was based on the ASTM E96-05 (ASTM, 2005). Mechanical properties of the films were determined according to ASTM standard method D882-10 (ASTM, 2010). With some modifications, the methods described by Tunc et al., (2007) and Rhim et al., (2006) were used to determine MU and WS, respectively. Water contact angle (WCA) measurements were performed by the sessile drop procedure. The statistical analyses on a completely randomized design and were carried out using analysis of variance (ANOVA). Duncan’s multiple range test (p < 0.05) was used to detect differences among the mean values of the functional properties.
Results and discussion: XRD demonstrated the change of MMT layers dispersion pattern from exfoliation in binary PS-5%MMT films to exfoliation-intercalation in ternary PS-5MMT-TiO2 films. These results showed that TiO2 agglomerates are formed in the starch matrix with MMT level more than 3% wt. This could be due to the interaction between starch and MMT tends to be more favorable than TiO2. Good dispersion of TiO2, high miscibility of with clay, and continuous phase can be obtained when the content of MMT discs is low. Due to the strong interfacial interaction between the starch and MMT, the tensile strength (TS) increased considerably from4.86 to 5.24 MPa, while the elongation at break (EB) decreased significantly from 78.23 to 71.93%, As the MMT concentration varied from 3 to 5%. The TS of nanocomposite films were further improved after the incorporation of TiO2. Suitable dispersal of TiO2, and creation of new interactions in the PS-MMT network, causes to increase the tensile strength of nanocomposites. The TS and EB values of PS-3MMT-1TiO2 nanocomposite film was higher than that of the other films. This is indicative of a synergistic effect between TiO2 and MMT which increases the tensile strength and does not decrease the EB. In the PS-5% MMT films, both mechanical characteristics were reduced. WVP shows more evidences of synergistic effect of combination of 1D MMT and 3D TiO2 on starch films. WVP reduction by MMT has been attributed to tortuous pathway which created by clay layers in the starch matrix. MMT platelets are water vapor impermeable, thus exfoliation of MMT reduce the voids in starch matrix. The PS-3MMT-2TiO2 nanocomposite showed the lowest WVP as compared to other PS films. WVP was reduced significantly from 5.84 × 10-7 g/m.h.Pa in the PS-3%MMT binary film to 3.04 × 10-7 g/m.h.Pa in the PS-3%MMT-2%TiO2 ternary film. TiO2 have low water solubility and hydrophobicity compared with starch and MMT. Thus, significant decrement of WVP in the prophase of TiO2 connoted that TiO2 was obstructing the nano- and micro-pathways in the PS films network. With addition of MMT and TiO2 content the water solubility and moisture absorption were reduced significantly. Results of water contact angle test confirmed the results of moisture absorption, solubility in water and water vapor permeability and showed that the addition of TiO2 increased the surface hydrophobicity of starch-MMT films as with addition of 2% titanium dioxide in PS-3% MMT and PS-5% MMT films, the contact angle after 60 seconds increased 4 and 15 degree respectively. As a result, 1% wt TiO2 nanoparticles (FDA maximum allowable) can be regarded as the optimum concentration and the developed starch based nanocomposite films can enable undertaking applications as appropriate candidates in food packaging systems.
Atefeh Farahmand; Fateme Mousavi Baygi; Masoud Taghizadeh; Amin Ziaforoughi
Abstract
Introduction: One of the most important aspects of food preservation is controlling the moisture of material such as fruits.Dryingis considered as important method to controlbacteriasafely using reduction of moisture. The hot air drying method has been widely adopted in manufacturing of conventional ...
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Introduction: One of the most important aspects of food preservation is controlling the moisture of material such as fruits.Dryingis considered as important method to controlbacteriasafely using reduction of moisture. The hot air drying method has been widely adopted in manufacturing of conventional dried food.Nowadays, Infrared radiation (IR) has significant advantages over conventional drying. Among these advantages,higher drying rates giving significant energy savings anduniform temperature distribution giving a better quality of product. Therefore, it can be used as an energy saving drying method. Earlier attempts forapplying infrared waves to drying of agricultural materials have been reported in the literatures, such as banana, onion, garlic, apple, corn, pomegranate seeds and peach. The persimmon (Diospyros kaki) is native to East Asia, most likely China. This fruit has very short shelf-life; it is due to thehigh soluble tannin content of the fruit during storage even at refrigerated conditions. The persimmon is mainly eaten fresh, but can be dried.Duringdrying the tannin cells coagulate, so astringency is removed and the sugars in the fruit exude to the surface where they crystallize, thus producing a sweet, candied product. The objective of this study was to examine the drying behavior of the far infrared and hot- air drying of persimmon slices by comparing the physical quality. Materials and methods: Persimmon (Diospyros kaki) used in this study was purchased from a local market (KhorasanRazavi, Mashhad). The whole samples were stored at 4°C. The initial moisture content of persimmon was found to be 78.2 kg H2O/kg moisture. The sampleswerecut into 5mm slices using a cutting machine and were dried to 10% final moisture (wet basis). - Infrared dryer setup: Infrared (IR) dryer used in this research was equipped with IR lamp (1300W). Persimmon slices were placed in a single layer on the drying tray and heated from one side. Thermocouples (Type K) were inserted at the center of persimmon slice.IR drying tests were conducted with final product temperatures controlled at 50°C, 60°C and 70°C. -Hot air dryer setup: Persimmon slices were arranged in a single layer on the trays and dried in cabinet dryer at material temperatures of 50°C, 60°C and 70°C.Air velocity in the dryer was 1.5 m/s. -Quality evaluation: Persimmon slice drying characteristics including rehydration ratio, color parameters, shrinkage, texture and sensory properties were investigated ResultsandDiscussion: It is clear that the moisture content and drying rate decrease continuously with drying time. The drying rate was rapid during the initial period but it became very slow at the last stages of dryingprocess. Persimmonslices dried with hot-air and infrared dryer at temperatures 60 and 70◦c respectively, had a maximum rehydration ratio. In general, infrared drying showed significant effect on L value (p
