Development and evaluation of antibacterial electrospun pea protein isolate-polyvinyl alcohol nanocomposite mats incorporated with cinnamaldehyde.

Electrospun film is developed from an electrically charged ultrafine jet of a polymer solution or melt as a matrix of thin/nano fibers struck on to a target surface. The objective of this work was to obtain homogeneous nanofibers from pea protein isolate (PPI) in polyvinyl alcohol (PVA) by hybrid electrospinning as well as incorporating cinnamaldehyde (CA) into the matrix to obtain an antibacterial mat. The effect of processing conditions, pH, polymer and CA concentrations on formulation properties and nanofiber morphology were investigated and the mats were visualized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Rheological evaluation indicated a pseudoplastic behavior for all formulations. Alkaline pH formulation led to a decreasing apparent viscosity and an increasing electrical conductivity resulting in the formation of more homogeneous fibers. The 50:50 mass percentage ratio of PPI/PVA solutions produced homogeneous nanofibers with the average fiber diameter of 485 ±â€¯85 nm. FTIR spectroscopy confirmed uniform dispersion of PPI and PVA. The minimum concentration of CA to inhibit both Gram negative and Gram positive bacteria was 1%. The average diameter of nanofibers decreased from 257 ±â€¯51 nm to 219 ±â€¯31 nm by increasing CA content from 0.25 to 1.5%.

Postharvest sour cherry quality and safety maintenance by exposure to Hot- water or treatment with fresh Aloe vera gel.

Iranian sour cherries (Prunus cerasus) were coated with fresh Aloe vera gel or treated with hot water (40 ± 2 °C) for 2 min and stored for 17 days at 4 ± 1 °C. The physicochemical characteristics of gel coated and hot water treated samples were compared with untreated fruit during the cold storage period. Untreated fruit showed increased respiration rate, rapid weight loss and colour change, accelerated aging and ripening. On the contrary, sour cherries, particularly those coated with gel significantly delayed the above mentioned parameters allowing a fruit storability extension. The sensory analysis in both treatments revealed beneficial effects in terms of delaying dehydration, maintenance of fruit visual aspect without any detrimental effect on taste, aroma or flavours. Consequently, Aloe vera gel coating and immersion in hot water maintained the properties during postharvest storage of sour cherries and could be introduced as two valuable, simple and non-contaminating treatments.

Recent innovations in the area of edible films and coatings.

Edible films/coatings have been considered as one of the potential technologies that can be used to increase the storability of foods and to improve the existent packaging technology, helping to ensure the microbial safety and the preservation of food from the influence of external factors. Innovations constantly appear in food packaging, always aiming at creating a more efficient quality preservation system while improving foods' attractiveness and marketability. The utilization of renewable sources for packaging materials, such as hydrocolloids and lipids from biological origin, is one the main trends of the industry. These films should have acceptable sensory characteristics, appropriate barrier properties (CO2, O2, water, oil), microbial, biochemical and physicochemical stability, they should be safe, and produced by simple technology in low cost. Also they can act as effective carrier for antioxidant, flavor, color and nutritional or anti-microbial additives. Nowadays, a great discussion exists about the potential applications of edible films/coatings on food products. The general trend is to find the correct combination between the food product and the edible film/coating, which will ensure the success of the technology.

Use of osmotic dehydration to improve fruits and vegetables quality during processing.

Osmotic treatment describes a preparation step to further processing of foods involving simultaneous transient moisture loss and solids gain when immersing in osmotic solutions, resulting in partial drying and improving the overall quality of food products. The different aspects of the osmotic dehydration (OD) technology namely the solutes employed, solutions characteristics used, process variables influence, as well as, the quality characteristics of the osmodehydrated products will be discussed in this review. As the process is carried out at mild temperatures and the moisture is removed by a liquid diffusion process, phase change that would be present in the other drying processes will be avoided, resulting in high quality products and may also lead to substantial energy savings. To optimize this process, modeling of the mass transfer phenomenon can improve high product quality. Several techniques such as microwave heating, vacuum, high pressure, pulsed electric field, etc. may be employed during or after osmotic treatment to enhance performance of the osmotic dehydration. Moreover new technologies used in osmotic dehydration will be discussed. Patents on osmotic dehydration of fruits and vegetables are also discussed in this article.

Use of edible films and coatings to extend the shelf life of food products.

The increased consumer demand for high quality, extended shelf life, ready to eat foods has initiated the development of several innovative techniques to keep their natural and fresh appearance as long as possible and at the same time render them safe. Packaging has been an important element in these preservation concepts for providing the appropriate (mechanical and functional) protection to the commodity. Since synthetic packaging materials contribute to the environmental pollution, edible coatings and packages have been proposed to replace or complement conventional packaging. Biodegradable and edible films and coatings are made from naturally occurring polymers and functional ingredients, and formed on the surface of food products. Edible films and coating have long been known to protect perishable food products from deterioration and reduce quality loss. These films should have acceptable sensory characteristics, appropriate barrier properties (CO(2), O(2), water, oil), microbial, biochemical and physicochemical stability, they should be safe, and be produced by simple technology in low cost. Also they can act as effective carrier for antioxidant, flavor, color, nutritional or anti-microbial additives. Patents on edible films and food products are also discussed in this article.