جستجوی مقالات مرتبط با کلیدواژه "edible films" در نشریات گروه "پزشکی"

Backgraound: 

Polysaccharides, particularly Carboxymethyl Cellulose (CMC) and Ammoniacum Gum (AMG), are considered valuable due to their thermal stability and non-toxicity. CMC has good film-forming ability but weak mechanical properties, while AMG shows promise with its unique chemical composition. Additionally, essential oils, such as Clove Essential Oil (CEO), are being used to enhance the antimicrobial properties of edible films, offering a natural way to extend the shelf life of food products.

This study investigated the combined effect of CMC: 0.5-1.5 wt %, AMG: 1-5 wt %, as well as CEO: 0-30 v/v % on the physical characteristics of the CMC-AMG films by Response Surface Methodology. The optimization was performed with the aim of maximizing Whiteness Index, Ultimate Tensile Strength (UTS), and Strain at Break (SB) and minimizing total color difference (ΔE) values. Fourier-Transform Infrared Spectroscopy, film microstructure, Differential Scanning Calorimeter analysis, and antibacterial activity were investigated. The analysis was conducted using Design Expert software version 10.00 (STAT-EASE Inc., Minneapolis, USA).

The films with the highest UTS have been obtained through a composition of 5 g CMC, 1.5 g AMG, and 15% CEO. On the contrary, using a composition of 5 g CMC, 1 g AMG, and 30% CEO revealed the highest SB (115.41%). The highest UTS value of 13.17 MPa was obtained with a formulation consisting of 5% AMG, 1.5% CMC, and 15% CEO. Nevertheless, the maximum SB value of 115.41% was achieved with a formulation containing 5% AMG, 1% CMC, and 30% CEO. Moreover, heterogeneous microstructure and more opaque films were obtained as identified by the higher ΔE. The Differential Scanning Calorimeter results demonstrated that incorporating a CEO did not impinge on thermal stability. Furthermore, the addition of CEO led to a rise in antimicrobial activity against Salmonella enterica, Pseudomonas fluorescens, Escherichia coli, and Listeria monocytogenes.

In conclusion, combination of CMC and AMG in optimum levels, led to the production of a film with acceptable mechanical properties. Also, these films showed significant antimicrobial activity.

Preserving the quality and safety of fish and its products is a critical concern for food industry. In the present study, the effect of green tea extract and olive leaves extract-based preservative coatings on chemical, microbial, and sensory quality of wild type Nile tilapia (Oreochromis niloticus) was determined during pre-freezing ice and subsequent frozen storage.

Forty-eight ponds raised tilapia, freshly caught in April, 2021, which were divided into three groups: group CT with no coating, group GTE with green tea extract-based coating, and group OLE with olive leaves extract-based coating. Fish samples in all groups were kept in ice for five days (1±2 °C) and then subjected to freezing (-18±2 °C) for 105 days. Chemical (moisture, ash, protein, fat, Total Volatile Basic-Nitrogen (TVB-N), pH) and microbial (Aerobic Plate Count (APC), Total Coliform (TC), Faecal Coliform (FC), Escherichia coli) parameters as well as sensory attributes (appearance, odour, acceptability, flesh color, Total Quality Index (TQI)) of tilapia in all groups were analysed after five days of ice storage and 15, 45, 75, and 105 days of frozen storage.

APC of tilapia treated with preservative coatings remained below the permissible limit (<5×105 Colony Forming Unit (CFU)/g) throughout the storage period. After five days, content of TVB-N in untreated samples of tilapia was 32.94±2.30 mg/100 g compared to 5.05±2.19 and 7.24±2.89 mg/100 g in tilapia treated with green tea and olive leaves extract-based coating, respectively. Fat content of untreated tilapia was significantly (p<0.05) reduced to 0.05±0.01% at the end of the study period from the the initial content of 0.24±0.04%. However, the tilapia treated with preservative coatings achieved significantly (p<0.05) lower scores of TQI compared with the untreated one owing to the coloration of fish with extract solution.

Green tea extract and olive leaves extract-based coatings can, therefore, be used to improve fish quality and safety during storage. However, there is a need to change consumer’s perception about the sensory attributes of fish.

Edible film is a food packaging that can be eaten directly and have protection function of outside contamination. The purpose of this research is to know how about the effect of using a glycerol plasticizer to film whey-konjac edible films that enriched with clove essential oil.

A completely randomized design was used by different clove essential oil including P10, 0% clove essential oil; P10C1, 5% clove essential oil; P10C2, 10% clove essential oil; and P10C3, 15% clove essential oil. The present study investigated the physical characteristics, including tensile strength, elongation, Water Vapour Transmission Rate (WVTR), and microstructur film. Data were statistically evaluated using an Analysis of Variance (ANOVA) in Statistical Program for Social Science (SPSS) 16.0.

Results showed that the addition of glycerol plasticizer enriched with clove essential oil had no significant difference (p>0.05) to value of tensile strength, elongation, and WVTR of whey- konjac edible film. The value of tensile strength with the addition of clove essential oil at doses of 0, 5, 10, and 15% were 9.16, 7.9, 7.1, and 6.52 N, respectively. The concentration of 5% clove essential oil resulted in the best physical properties of film with a tensile strength 7.90 N, elongation 64.0%, and WVTR 8.12 g/mm2/day.

Use of clove essential oil with different concentrations had no effect on tensile strength, elongation, and WVTR; but the addition of clove essential oil had promising potential to improve the physical characteristic of whey-konjac edible films.

Food spoilage is one of the major elements of food insecurity that has acquired significant attention over recent decades due to global human population growth. Several studies have investigated increasing shelf life of food products using natural and environmentally friendly compounds. Whey protein (WP) can be an important additive material because it is well-known for its high value of nutrition and well characteristics for the formation of edible films. Furthermore, natural bioactive compounds have been incorporated with WP-based films to confer their antioxidant and antimicrobial activities. Herein, nanotechnology has been effectively potentiated the antimicrobial and antioxidant properties of WP films. A wide range of bioactive agents has been embedded in the WP films, such as essential oils (EOs), TiO2, nano-clay, and even lactic acid bacteria. The current paper reviews the antioxidant and antimicrobial effects of different types of WP films and their applications in food products. This study also discussed the impact of WP films on shelf life, chemical and microbiological quality indices of meats, processed meats, poultry meat products, and fish.

A novel edible film was developed using Lallemantia peltata (L.) seed gum (LSG), and its water sensitivity, physico-mechanical, barriers, microstructural and thermal properties as a function of glycerol concentration (20, 30, 40, 50 and 60% w/w) were studied. Different models were also used to investigate the water sorption of the LSG films. Unplasticized LSG films were brittle and difficult to handle which were effectively modified by glycerol addition. Water sensitivity, oxygen permeability, and elongation of LSG films were increased with increasing glycerol concentration. Also, increasing of glycerol concentration resulted in reduction of tensile strength, glass transition temperature (Tg) and melting temperature (Tm) of the films. Electron scanning micrographs revealed a smooth surfaceand compact cross-section microstructure in LSG films.The films showed sigmoid shape type II water sorption isotherms, representing typical features of most of biopolymers. Accordingly, the results suggest that LSG films containing desired glycerol concentration could potentially be used as edible films in food packaging.

Due to the advantages of sourdough, its film production for food packaging could be interesting. This study aimed to evaluate the influence of probiotic sourdough based edible film covered on set yogurt and subsequent changes during post fermentation storage.

The parameters examined included changes to the fermentation characteristics (pH, and viable counts of probiotic bacteria), synersies, and sensory evaluation during 21-d storage at 4°C. lactobacillus plantarum was supplemented with sourdough films and yogurt produced by commercial yogurt starters (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) then films placed on yogurt containers, and a panel of parameters reflecting product quality was subsequently monitored along with 21-d post-fermentation storage.

Results demonstrated that the pH value of yogurt decreased slowly during the storage and no significant difference was observed between the control and the samples with the films. Although the number of viable cells decreased during storage, it did not lower than the minimum requirement for probiotics (> 107 log CFU / g). The synersies of the film-treated samples were significantly (P ≤ 0.05) lower than the control samples. The yogurt with the film without bacteria had the least synersis. Film-treated yogurts had acceptable sensory properties in comparison with control.

Sourdough films can be an optimizing candidate to enter the food industry as a bioactive edible film and also could improve the delivery of probiotic bacteria.

Environmental concerns related to using plastics for food packaging and consumers' demand for the extended shelf life of foods conducted the researches to develop new strategies for food packaging. The shelf life of food systems is related to the existence and growth of food pathogenic and spoilage microorganisms during food storage. Also, the environmentally friendly aspects of edible films and coatings make them appropriate substitutes for plastics in food packaging systems. Therefore, edible films and coatings which contain a food preservative introduced as hopeful novel systems for extending shelf life and preserving the quality of foods. The antimicrobial agents could be used in edible films and coating for restriction or stopping the microbial growth for prolonging the shelf life of foods. Due to the weak barrier and mechanical characteristics of most edible films and coatings, natural nanocrystals could be employed to improve the properties of them. In this review, the nanoemulsion encapsulation introduced as a technique for improving antimicrobial properties, while minimizing the antimicrobial agent impacts on the foods' organoleptic properties. Also, using natural nanocrystals proposed as a reinforcing agent for edible packaging material. The shelf life of food systems is related to the existence and growth of food pathogenic and spoilage microorganisms during food storage.

 Biodegradable film is widely used because it is free from synthetic substances and does not lead to environment pollution. This study aimed to prepare and characterize biodegradable sago starch films loaded with Carboxymethyl Cellulose nanoparticles.  Sago starch films were prepared and plasticized with sorbitol/ glycerol by the casting method. Nano Carboxymethyl Cellulose with 0%, 1%, 2%, 3%, 4% and 5% (w/w) was added to the films before casting them. The effects of the addition of nanoparticles were measured on mechanical properties, water absorption capacity, density and heat sealability.  In mechanical test of the combined films, by increasing of CMC nanoparticles concentration significantly (P<0.05) increased tensile strength and Young Modulus and elongation prameter showed significant (P<0.05) reduction from 17.69 to 15.39. The seal strength for the sago film was increased by incorporating a low percentage of nano Carboxymethyl Cellulose and enhanced the physicochemical properties and heat sealability of sago films.  Considering biodegradability of the edible films and improvement of their mechanical properties by CMC nanoparticles, they can be utilized in different industries, particularly in food industry, as an edible coating for packaging food and pharmaceutical products. With regard to its properties such as cost saving, biodegradability and mechanical properties when percentage of CMC nanoparticles increased can found a position among packaging materials.

Food packaging extensively uses plastic films and containers of petroleum-based polymers for their excellent functional properties and competitive price. Plastic packaging has become a central focus of waste reduction efforts, particularly in aesthetic terms of damage to flora and fauna. Presently, consumers require greater quality and longer shelf lives for their foodstuffs, while they demand a reduction in the quantity of packaging materials used. In the present study, poly-ethylenglycol (PEG), glycerol, and olive oil were incorporated into whey protein concentrate (WPC) through emulsification to produce films. Whey protein films were prepared by dispersing 10% whey protein concentrate in tap water and plasticized with different levels of glycerol, PEG or olive oil. The emulsion films were evaluated for mechanical properties, water vapor permeability (WVP) and opacity. Increasing the levels of glycerol or PEG in the films resulted in a decrease in modulus and tensile strength. Increasing glycerol content of the films at oil/protein ratios of 0.2 and 0.4 led to slight increases in elongation. Increasing the oil/protein ratio further resulted in a decrease in elongation for all films. No significant difference in WVP and opacity was observed between films made from mixtures of various proportions of whey protein concentrate-glycerol with increasing PEG (addition) at all levels of the plasticizer. These results suggest that a whey protein based edible films is a viable alternative packaging process for food and improvement of shelf life.