The food industry nowadays is facing new challenges in terms of sustainability and health implications of packaging and processing techniques. Due to their desire for new and natural products coupled ...with changes in lifestyle, consumers are looking for food products that have been less processed but possess longer shelf life and maintain nutritional and sensorial proprieties during storage. These requirements represent real challenges when dealing with highly perishable food products, such as fruits and vegetables. Thus, in recent years, edible coatings have been intensively developed and studied because of their capacity to improve the quality, shelf life, safety, and functionality of the treated products. Edible coatings can be applied through different techniques, like dipping, spraying, or coating, in order to control moisture transfer, gas exchange, or oxidative processes. Furthermore, some functional ingredients can be incorporated into an edible matrix and applied on the surface of foods, thus enhancing safety or even nutritional and sensory attributes. In the case of coated fruits and vegetables, their quality parameters, such as color, firmness, microbial load, decay ratio, weight loss, sensorial attributes, and nutritional parameters, which are very specific to the type of products and their storage conditions, should be carefully monitored. This review attempts to summarize recent studies of different edible coatings (polysaccharides, proteins, lipids, and composites) as carriers of functional ingredients (antimicrobials, texture enhancers, and nutraceuticals) applied on different minimally processed fruits and vegetables, highlighting the coating ingredients, the application methods and the effects on food shelf life and quality.
Edible coatings and films have been researched for more than three decades due to their ability to be incorporated with different functional ingredients or compounds as an option to maintain the ...postharvest quality of fruits and vegetables. The aim of this study was to evaluate the effect of three types of chitosan-based (CH) edible coatings obtained from medium and high molecular weight chitosan, containing ascorbic or acetic acid and sea buckthorn or grape seed essential oils on the physical–chemical and microbiological properties of organic strawberries and apple slices during cold storage at 4 °C and 8 °C. Scanning electron microscope images showed both a smooth structure and a fracture and pore structure on strawberry coatings and a dense and smooth structure on the apple slices coatings. Further, the edible coatings managed to reduce the microbial load of yeasts and molds of the coated strawberries during the storage period. Overall, the treatments preserved the ascorbic acid, total polyphenol content, and antioxidant activity for all the tested samples compared to the control sample, throughout the storage period. In addition, the water activity (aw) of the coated samples presented lower values (0.96–0.98) than the control samples. The obtained results indicate that the developed chitosan-based edible coatings could maintain the postharvest parameters of the tested samples, also leading to their shelf-life prolongation.
Consumers' concern regarding possible negative health effects of food products produced with intensive farming methods has led to a great interest in the health benefits of organically-produced ...fruits, vegetables and animal products. Given the significant increase in consumer interest toward this area, there is a need to determine to what extent there is a scientific basis for claims made for organic products. In this sense, studies comparing organic food products and conventional ones were assessed for the key area, nutritional quality. While the assessed articles have shown differences among organic and conventional foods in favour of organic ones, still the information is limited and more research needs to be done in order to draw unwavering conclusions that organic food products are superior compared to conventional ones.
•Organic farming is characterized by its restriction against the use of synthetic pesticides and fertilizers.•In organic compared to conventional husbandry, animals receive low amounts of concentrated feed.•Insufficient research done regarding the nutritional value assessed for both agricultural systems.•Organic food products appear to be of higher nutritional value compared to conventional ones.•Insufficient research done regading the impact of organic foods on human health.
In this study, sea buckthorn (Hippophae rhamnoides L.) pomace resulting from juice extraction was dried and ground in order to obtain a powder that was further used in bread making. Sea buckthorn ...pomace, an invaluable by-product of the industry, contains bioactive compounds and dietary fibers that promote health. Dried by-products of sea buckthorn are rich sources of nutritional and bioactive compounds, offering great potential for use as nutraceuticals in animal feed, ingredients in functional food, and the pharmaceutical industry. The utilization of sea buckthorn by-products promotes a circular and sustainable economy by implementing innovative methods and strategic approaches to recover high-value products and minimize waste in multiple ways. For this purpose, three organic sea buckthorn varieties were used, namely Mara (M), Clara (C), and Sorana (S). Further, 6%, 8%, and 10% pomace powder were added to wheat flour to prepare functional bread, and its effects on structural, nutritional, and sensorial characteristics were investigated. The volume, porosity, and elasticity of the obtained bread samples were slightly lower compared to the control sample (white bread). The nutritional characteristics revealed that the developed bread presented higher antioxidant activity, polyphenolic content, and crude fiber compared to the control sample. The acceptability test showed that consumer preferences were directed toward the bread samples containing 8% sea buckthorn powder, regardless of the variety, while the addition of 10% pomace powder led to major sensorial changes. The results of this study showed that sea buckthorn pomace powder can be successfully incorporated into bread in order to obtain a food product with enhanced properties.
The effect of chitosan (CH) concentration on the properties of biocomposites containing plasticized poly(lactic acid) (PLA) with tributyl o-acetyl citrate (ATBC) was studied both in respect with ...changes in properties and antifungal/antimicrobial activities. It was found that ATBC reduced brittlenes of PLA, the sheets and films obtained from plasticized PLA/CH biocomposites have satisfactory transparence, mechanical and improved thermal properties. The PLA/CH biocomposites are not toxics for germination of cucumber and radish seeds. Migration tests performed in two food simulants and one modified to avoid high temperatures which are near glass transition of PLA showed that such biocomposites are suitable materials for the packaging of non-fatty foods with a pH above 4.5 at refrigeration temperature. All prepared PLA-based materials showed good antifungal activity against Aspergillus brasiliensis ATCC 16404, Penicillium corylophilum CBMF1 and Fusarium graminearum G87 at the contact surface which increases by CH incorporation. As it concerns antimicrobial activity only biocomposites containing CH exhibit significant reduction in S. aureus and E. coli on the contact surfaces.
The goal of the present paper is to explore the properties of medium molecular-weight chitosan/polyvinyl alcohol blends mixed in volume ratios of 75:25, 50:50, and 25:75 obtained by solution casting. ...Cross-linked chitosan/poly(vinyl alcohol) nanostructures were obtained by treating these blends with 5% (v/v) glutaraldehyde. The prepared chitosan/polyvinyl alcohol films were characterized by attenuated total reflectance - Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering, and cytotoxicity, while the nanostructured materials were examined by scanning electron microscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and X-ray diffraction. Also, the removal of lead(II) ions from aqueous solution by adsorbents nanostructures was studied in the batch adsorption mode. The effects of adsorbent dosages, initial metal concentration, and contact time on the adsorption capacity were investigated. The FT-IR spectra indicated the interactions of polyvinyl alcohol with chitosan. DSC and TGA analyses revealed the loss of water up to 100 °C. The zeta potential and mobility of the prepared nanostructures were enhanced with the increasing ratio of the cationic polymer. The results showed that the 100% chitosan adsorbent provided the highest removal of Pb(II) during the first 15 min (̴94%). The chitosan100/polyvinyl alcohol0 and chitosan75/polyvinyl alcohol25 nanostructures fitted well with the Langmuir isotherm model. The maximum adsorption capacities for Pb(II) ions reached maxima of 7.36 and 7.67 mg/g, respectively. The Freundlich isotherm model best described the Pb(II) adsorption on the 50% chitosan/50% polyvinyl alcohol and 25% chitosan/75% polyvinyl alcohol adsorbents. Furthermore, (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay results demonstrated that chitosan/polyvinyl alcohol films are biocompatible with more than 90% cell viability.
The preservation of food represents one of the greatest challenges in the food industry. Active packaging materials are obtained through the incorporation of antimicrobial and/or antioxidant ...compounds in order to improve their functionality. Further, these materials are used for food packaging applications for shelf-life extension and fulfilling consumer demands for minimal processed foods with great quality and safety. The incorporation of antimicrobial peptides, such as nisin, has been studied lately, with a great interest applied to the food industry. Antimicrobials can be incorporated in various matrices such as nanofibers, nanoemulsions, nanoliposomes, or nanoparticles, which are further used for packaging. Despite the widespread application of nisin as an antimicrobial by directly incorporating it into various foods, the use of nisin by incorporating it into food packaging materials is researched at a much smaller scale. The researchers in this field are still in full development, being specific to the type of product studied. The purpose of this study was to present recent results obtained as a result of using nisin as an antimicrobial agent in food packaging materials, with a focus on applications on products of animal origin. The findings showed that nisin incorporated in packaging materials led to a significant reduction in the bacterial load (the total viable count or inoculated strains), maintained product attributes (physical, chemical, and sensorial), and prolonged their shelf-life.
The chitosan effect on the soil burial degradation of polylactic acid plasticized with tributyl o-acetyl citrate (ATBC) was studied by weight loss measurements, changes in average molecular weight ...and its distribution, mechanical, thermal and surface properties correlated with structural and morphological modifications. Besides the loss of transparency at the end of environmental degradation test, all composites became brittle. During degradation, Young modulus increases while elongation at break significantly decreased, mainly for the biocomposites with high content of chitosan which also showed a significant decrease of average molecular weight, increase of glass transition temperature and crystallinity degree values and decrease of cold crystallization and melting temperature when soil burial period is longer. The high content of chitosan led to increased hydrophilicity of biocomposite surfaces which favors interaction with moisture and attack of microorganisms. Chitosan as hydrophilic compound promotes the soil burial degradation of PLA. However, longer period of soil burial are necessary for totally degradation of the sheets of plasticized PLA/CS biocomposites.
Foodborne pathogens represent one of the most dangerous threats to public health along the food chain all over the world. Over time, many methods were studied for pathogen inhibition in food, such as ...the development of novel packaging materials with enhanced properties for microorganisms’ growth inhibition (coatings, films) and the use of emerging technologies, like ultrasound, radio frequency or microwave. The aim of this study was to evaluate the current trends in the food industry for pathogenic microorganisms’ inhibition and food preservation in two directions, namely technology used for food processing and novel packaging materials development. Five technologies were discussed in this study, namely high-voltage atmospheric cold plasma (HVACP), High-Pressure Processing (HPP), microwaves, radio frequency (RF) heating and ultrasound. These technologies proved to be efficient in the reduction of pathogenic microbial loads in different food products. Further, a series of studies were performed, related to novel packaging material development, by using a series of antimicrobial agents such as natural extracts, bacteriocins or antimicrobial nanoparticles. These materials proved to be efficient in the inhibition of a wide range of microorganisms, including Gram-negative and Gram-positive bacteria, fungi and yeasts.
The antifungal, antibacterial, and antioxidant activity of four commercial essential oils (EOs) (thyme, clove, rosemary, and tea tree) from Romanian production were studied in order to assess them as ...bioactive compounds for active food packaging applications. The chemical composition of the oils was determined with the Folin-Ciocâlteu method and gas chromatography coupled with mass spectrometry and flame ionization detectors, and it was found that they respect the AFNOR/ISO standard limits. The EOs were tested against three food spoilage fungi-
,
and
-and three potential pathogenic food bacteria-
,
and
-using the disc diffusion method. It was found that the EOs of thyme, clove, and tea tree can be used as antimicrobial agents against the tested fungi and bacteria, thyme having the highest inhibitory effect. Concerning antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS) methods, it has been established that the clove oil exhibits the highest activity because of its high phenolic content. Promising results were obtained by their incorporation into chitosan emulsions and films, which show potential for food packaging. Therefore, these essential oils could be suitable alternatives to chemical additives, satisfying the consumer demand for naturally preserved food products ensuring its safety.
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