جستجوی مقالات مرتبط با کلیدواژه « active film » در نشریات گروه « صنایع غذایی »

This research aimed to examine the potential of increasing the shelf life of Hypophthalmichthys molitrix (silver carp) fillets using basil seed gum-based film enriched by various concentrations (0, 0.5, 1, 1.5, and 2% /dry matter) of Echinophora platyloba extract (EPE) during a 16-day storage period. Each characteristic of basil seed gum-based films enriched by EPE followed a specific trend. The results showed that with increasing EPE, the film thickness, length to the rupture point, and antioxidant activity of film increased; however, the film with the highest concentration of EPE had the lowest solubility (19%) and tensile strength (15 MPa). The film loaded with 2% EPE overall presented acceptable physicchemical properties and was used for wrapping (optimum film). The fillets wrapped by the optimum film on the 16th day of storage indicated a lower total volatile basic nitrogen (TVB-N) value (36 mg N/100 g meat) compared to the nonenriched film (60 mg N/100 g meat) as well as the control sample (65 mg N/100 g meat). The fillet sample wrapped by basil seed gum-based film enriched with 2% EPE had lower pH and thiobarbituric acid index, peroxide index, and microbial load after 16 days of storage compared to the basil seed film sample without the extract and control sample. The obtained results encourage the use of basil seed gum-based film containing EPE in active food packaging systems to extend the shelf life of silver carp fillets.

The aim of this research was to fabricate wheat gluten based active film containing free and encapsulated Marjoram essential oil (MEO). The MEO was encapsulated by lipid nanocarrier (nanoemulsion) and protein-based nanocarrier (Pickering emulsion by WPI) and used at the concentrations of 1, 3 and 5% in the formulation of gluten films. The free MEO was used at same concentrations. The physical properties of active films and also their performance in the control of microbial spoilage in the real food models including UF cheese and red meat during 9 days of storage were evaluated. The results indicated that the water vapor permeability (WVP) increasesd by increasing free MEO but the encapsulated MEO caused to significant decrease in the WVP values (p<0/05). The tensile strength, Young’s modulus and elongation to break of films decreased by adding free MEO but the encapsulated samples caused to improve the mechanical properties. Moreover, the results of the colony counting of E.coli and L. monocytogenes cultured on the surface of UF cheese and red meat wrapped with active films, indicated that for all samples, the microbial growth had increasing manner during storage and by increasing the concentration of MEO, the microbial count decreased significantly in comparison to the control sample (p<0.05). The encapsulation had no adverse effect on the antimicrobial activity of MEO. Generally, the results of this research indicated that loading of encapsulated MEO causes to improve the physical properties of active gluten film and is able to control the microbial growth in Ultra-refined cheese and meat.

The aim of this study was to prepare antimicrobial and antioxidant films based on wheat gluten and Heracleum persicum essential oil, magnesium oxide nanoparticles and polypyrrole were used to improve the structure of films. Response surface statistical design was used to investigate the effect of the essence, magnesium oxide nanoparticles and polypyrrole on the physicochemical properties of the films. According to the obtained results, moisture absorption, solubility and water vapor permeability of the films decreased with increasing the content of essential oil and pyrrole. Increasing the amount of essential oil and pyrrole in the film structure improved the mechanical properties of the films. Then, the optimal films (containing 12% essential oil, 0.904% magnesium oxide and 0.2 pyrrole) were studied to evaluate the structural and antimicrobial properties. The antibacterial, antioxidant and electrical conductivity of the film was greatly increased in the presence of all three additives of essence, magnesium oxide nanoparticles and polypyrrole (P <0.05). Gluten-essence-MgO-PPy (Glu-E-MgO-PPy) composite film had the highest antioxidant and antibacterial properties. The optimal film had higher antibacterial activity against Escherichia Coli ATCC13706 compared with Staphylococcus aureus ATCC6538. SEM images showed that the essence and polypyrrole strengthened the gluten film structure and made it more resistant to the passage of water vapor. FTIR spectra confirmed the electrostatic interactions between gluten and essence and polypyrrole. The results of thermal analysis showed that polypyrrole greatly increased the thermal resistance of the film and the nanoparticles had little effect on the thermal resistance. The results of this study showed that composite and bioactive film with three important properties of electrical conductivity, antibacterial and antioxidant has the potential to be used as an active and intelligent film in the packaging of perishable food products.

Active films and edible coatings are used to protect, improve quality and extend the shelf life of food products. The aim of this study was to produce an active film based on chitosan containing different concentrations of Barije essential oil (BEO) from 1 to 2% (w/w) and investigation its chemical composition, physicochemical properties, mechanical structure, antioxidant and antimicrobial activity in the produced films. The major components of BEO were identified by using gas chromatography (GC/MS): β-Pinene (55.5%), α-pinene (12.3%), bulnesol (8.3%), guaiol (6.4%), and myrcene (2.6%), respectively. The incorporation of BEO into film increased the thickness and contact angle (CA), but reduced moisture content (MC), water solubility (WS) and water vapor permeability (WVP). Chitosan/BEO films were less resistant to breakage, more flexible and more opaque than the control film. BEO increased the absorption of color in the visible region, which in turn led to increase of the parameter b* but reduced of a* and L* parameters. In the investigation of antimicrobial activity of the films containing essential oil, Staphylococcus aureus was identified as the most sensitive bacterium and Pseudomonas aeruginosa as the most resistant bacterium. The film containing essential oil showed good antioxidant properties, which by increasing the essential oil concentration by up to 2% improved total phenolic content and activity of scavenging free radicals.

In recent decade, developing natural biodegradable films carrying bio active material extracted from cheap agricultural wastes have fostered many attentions. This is due to increasing economic and environmental and health conservations. The purpose of this study first, is the production of an active biodegradable film based on chitosan and carboxymethyl cellulose and second, is the investigation of two different ways of incorporating nanoliposomes loaded with Pistachio green hall extract into the film on its physico-mechanical, chemical, antioxidant capacity and release properties.

Phenolic component of Pistachio green hall were extracted and purified and encapsulated into nanoliposomes. 10 film samples based on chitosan, carboxymethyl cellulose and glycerol as plasticizer incorporated with 0, 1, 1.5, %2 w/w layered and dispersed nanoliposome carrying 1000 ppm PGHE were developed. Total phenol content of PGHE, liposome dimension, loading efficiency, and mechanical resistance, optical property, antioxidant capacity and release property of extract of film samples were studied. Also FTIR analysis of the film samples was studied to search about probable interactions among film ingredients and liposomes.

All film samples showed desirable mechanical properties. However, film samples with 1.5 to 2% w/w liposome especially the sample containing dispersed liposomes significantly presented higher mechanical strength and the percentage of elongation. Also, the film samples with 1.5 to 2% w/w liposome demonstrated a high and concentration dependent antioxidant potential. The FTIR studies showed the specific peaks of the blank film components, indicating no probable interactions among the film ingredients and liposomes. Also, and electrostatic interaction of chitosan and carboxymethyl cellulose was detectable. The spectra of two both film samples containing liposome were similar to blank film sample, indicated no probable interactions among the film ingredients and liposomes. There was no significant difference among optical data showing that incorporating liposomes had no effect on the clarity of film samples. The release test showed the similar release kinetic between the sample with layered and the film sample incorporated with free extract. This finding cleared that antioxidant components could release without any delay and struggling with film polymer strands.

Although all prepared film samples had notable optical, mechanical and tensile strength and antioxidant features, the film samples with %2 layered liposome besides exhibiting desire physico-mechanical, optical and antioxidant activity showed more efficient release kinetic of antioxidants. So, it could be concluded that the proposed method in this research could be a promising way for developing active biodegradable films.

In recent years, the tendency to use biodegradable polymers in food packaging has been increased due to enhanced awareness on the ecological and environmental problems and the contaminations of natural resources caused by non-degradable petrochemical-based polymers. In this regard, two types of biodegradable polymers have been investigated: edible and non-edible biopolymers. Carbohydrates and proteins or their combination with lipids usually are used for producing edible biopolymers (Noshirvani et al., 2018). Cinnamon essential oil (CEO) is a mixture of aldehyde, phenol and terpene active compounds, exhibiting antioxidant and wide spectrum antimicrobial properties against fungal spoilage. CEO is granted by the world health organization (WHO) expert committee as a non-toxic additive and flavoring agent, meanwhile CEO is widely applied in many food formulations thus it fits desirable taste (Ojagh et al., 2010). Mostly, synthetic antimicrobial and antioxidant compounds are directly added into the food products to control the microbial growth. This method may lead to the inactivation or evaporation of active agents and rapid migration into the bulk of the foods. Hence, the antimicrobial activity may be quickly lost by dilution below active concentration and also the flavor of the food may be changed. The incorporation of an antimicrobial compound in a polymer matrix and the production of active packaging potentially cause to gradual release of active agents, which may be promising approach to inhibit the microbial growth. Carboxymethyl cellulose (CMC) is a biodegradable semi-synthetic biopolymer. It is a linear anionic charge polysaccharide due to having many hydrophilic carboxyl groups. CMC produces high viscosity solution and transparent films with favorable properties from consumer point of view. The CMC-based films show good barrier properties against gases and lipophilic compounds, while showing poor inhibition against water vapor permeation, similar to other polysaccharide and protein-based films. In order to fix these defects and improve packaging properties, a number of approaches have been studied such as combination with other compatible biopolymers, using hydrophobic compounds (such as lipid and essential oil), cross linking agents and nanofillers. To our knowledge, there is no study on comparing the effects of nano and macro emulsion of cinnamon essential oil (CEO) on the physicochemical and antifungal properties of the active biopolymer based films. Therefore, the objectives of this work were (i) to produce the emulsified CMC-based films from CEO macroemulsions (ME) and nanoemulsions (NE) prepared by using Ultra-Turrax and Ultrasonication (ii) to compare the effects of these two types of the emulsified films on some physical features of the resulted films (iii) and to study the in-vitroefficiency of these films against Aspergillus niger and mucor racemous.

Macroemulsions (ME) were formed by adding different amounts (0.125, 0.25 or 0.5 gr) of Tween 80 equation with 50% W/W surfactant oil ratio (SOR) to 20 ml of double distilled water and followed by homogenization by Ultra-Turrax (JANKE & KUNKEL, Germany), at 20000 rpm for 1 min. Then, CEO was added at (0.25, 0.50 or 1 gr) equation with 0.25, 0.50 and 1% W/V (CEO/Emulsion) to each solution and mixed again for 2 min. Prepared ME were sonicated at the condition of 20 kHz frequency, 400 W input power and 70S amplitude for 10min by Ultrasonicator (FAPAN, Iran) to obtain nanoemulsions. In order to prevent the increase of emulsions temperature during sonication, the solutions were keeping in ice-water bath. Films were prepared as described by Dashipour et al. (2015), with slight modifications. First, 80 ml of double distilled water was heated in a water bath until temperature increased to about 85 , then, 1.5 g of CMC powder was added to hot water and mixed by magnetic stirrer(800 rpm) at 85 for 60 min. After that, glycerol was added at 0.75 w/w of CMC as a plasticizer and mixing continued for 10 min. Then, the solution temperature reduced to 60  in order to prevent the destruction of CEO active compounds. Having done that, the solution was mixed with 20 ml of macro and nano emulsions solution prepared in the previous section and agitated with magnetic stirrer (500 rpm) at 60  for 30 min to obtain homogeneous solutions. The film forming solutions were degassed with vacuum pump(DV-3E 250, JB,USA), at ambient condition for 5 min, then, 100 ml of the emulsified film forming solutions were poured into an even surface Teflon plates (PTFE) in the dimension of 15 15 cm and dried at 40  for 18 h in cold incubator to cast the films.

The emulsified films based on carboxymethyl cellulose (CMC) containing macroemulsion (ME) and nanoemulsion (NE) of cinnamon essential oil (CEO) were prepared. The atomic force microscopy (AFM) images showed different morphology in the ME and NE films and more compact and uniform microstructure in the NE films than the ME one. Adding CEO led to more flexible films with lower glass transition temperature (Tg) and storage modulus (E'). Low droplet size in NE than ME led to brighter and yellowish films. Antifungal index against A. niger and M.racemous were 14.16% and 20.82 % in the ME films and 18.81% and 25 % in the NE ones. The antifungal activities of cinnamon essential oil (CEO) is related to their major phenolic or aldehyde such as eugenol and cinnamaldehyde constituents, respectively. Eugenol caused to killed microbial cells probably by two important mechanisms; leached out cell content by increasing the permeability of cellular membranes and released proton of hydroxyl groups causing to reduce proton gradient that resulted depletion energy polls in microbial cells. Another effective mechanism of cinnamaldehyde in microbial growth is its reaction with nucleophilic compound in microorganism's structure by higher electrophilic compounds such as carbonyl groups in cinnamaldehyde structure. The disruption of cytoplasmic membranes, the cytoplasm depletion, thedeformation of hyphal tips, the formation of short branches and the collapse of entire hyphaewere the major effect of essential oil on fungus, observed by transmission electron microscopy.

Comparing different physicochemical and antifungal properties of CMC films containing ME and NE of CEO showed significant differences. The decrease of droplet size by sonicator caused to better diffusion of CEO NE from cell membrane of microorganisms, resulting in improved antifungal efficiency. Microscopic images showed smooth and homogenous appearance with lower Sa and Sq of NE films. More interruption among biopolymer chains by nano droplets caused to the production of the films more extensible than ME films. Thermomechanical analysis confirmed more decrease in glass transition temperature (Tg) and storage modulus (Eʹ). This study introduced a new nano active packaging film with some improved functional characteristics.