From 2018 to 2020, an experiment on effects of nitrogen top-dressing was conducted with Burley tobacco on the Zagreb experimental field at the Faculty of Agriculture. The experiment was set up ...according to the RCBD in four replications. Nitrogen was added to the top-dressing in five different variants: 1) control 100% from CAN; 2) 90% from CAN + 10% from microcapsules; 3) 80% from CAN + 20% from microcapsules; 4) 90% from CAN + 10% from microcapsules with chitosan; and 5) 80% from CAN + 20% from microcapsules with chitosan. During vegetation, number of leaves, length and width of the 9th leaf, topping height, and days to flowering were determined. After drying, the yield was determined, and the tobacco was classified into six classes. According to the analysis of variance, significant differences were established for share of I class, width od 9th leaf, topping height days to flowering in 2018, yield, share of VI class in 2019, yield, share of V class, and leaf number in 2020. Significantly, the highest yield had control compared to the variants 80% from CAN + 20% from microcapsules with chitosan in 2019 and the variants 80% from CAN + 20% from microcapsules in 2020. The control had the significantly highest share of I class in 2018. The highest leaf number in 2020 had the control and variant 90% from CAN + 10% from microcapsules with chitosan compared to the variant 80% from CAN + 20% from microcapsules with chitosan. The effect of microencapsulation has not given the expected results.
High-added value biological compounds (BACs) from herbal and plant sources, such as essential oils (EO), antioxidants and volatile compounds, often exhibit remarkable features, ranging from nutritive ...and medicinal properties, as well as antimicrobial and antioxidant activities, which can be exploited in the production of functional foods. However, most BACs exhibit low water solubility, strong off-flavors/odors, and are generally unstable and easily degraded under common processing and storage conditions. Encapsulation is a technology that enables the delivery in food systems, the protection, as well as the controlled and targeted release of BACs.
The aim of this review is to summarize the most important information for encapsulation of natural extracts using unconventional technologies.
Encapsulation is an excellent choice to stabilize BACs, and in particular EOs, and mask their strong flavors and odors. In particular, spray drying is one of the most economic and common encapsulation technologies. However, the challenges of reducing the operating costs, of developing high-throughput processes, of minimizing the use of organic solvents, and of increasing the level of functionality of the encapsulation systems are driving the research towards the implementation of innovative strategies and non-conventional methods, which incorporate the concepts of Green Food Processing.
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•Biological compounds from herbal and plant sources have remarkable features.•Encapsulation is a technology that enables their delivery in food systems.•Encapsulation of natural extracts can be achieved by unconventional technologies.
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•Alginate microspheres and microcapsules loaded with biofertilizer are prepared.•Microparticles exhibit a granular surface structure with substructures.•Microcapsules exhibit bigger ...grains and higher surface roughness than microspheres.•Loading with Trichoderma viride reduces microparticle surface roughness.•Microparticles morphology and structure affect active agents release kinetics and mechanisms.
The structure-property relationship in alginate microparticles (microspheres and microcapsules prepared with or without Trichoderma viride spores (Tv) was investigated. Surface morphology, structure and release behavior from alginate microparticles strongly depend on calcium concentration and presence of Tv and chitosan layer. All microparticles exhibited a granular surface structure with substructures consisting of abundant smaller particles. In vitro active agents release study revealed that the increase in calcium cation concentration reduced the release rate of Tv (˜84% for microspheres; ˜57% for microcapsules) and calcium cations (˜20% for microspheres; ˜23% for microcapsules). The average decrease in k values due to chitosan layer addition is 41% for Tv and 93% for calcium ions, respectively. The underlying Tv release mechanism from microspheres is anomalous transport kinetics, whereas from microcapsules is controlled by Type II transport. The differences in microparticle surface properties did not affect the mechanism controlling calcium ions release detected as diffusion through microparticles.
In recent years, the replacement of synthetic colorants with natural ones has attracted increasing consumers' and market interest. Natural colorants include different groups of pigments, many of ...which possess also pronounced biological potential. This review addresses the main issues related to the use of natural pigments in foods, starting from the sources available in nature, their chemical properties, stabilization processes, and applications in real foods, as discussed in the scientific literature reported in the main databases relevant to this topic (Scopus, Web of Science, PubMed, ScienceDirect, and Google Scholar). Notably, several natural pigments are available to cover different needs in terms of hues and intensities, and whose use is permitted in foods by the main regulatory agencies. However, their use is still frequently limited by their higher price and lower stability than synthetic counterparts. This review discusses in detail the main sources for natural pigments, focusing on the recent trends towards those more economically favorable, such as microbial sources and agro-industrial residues. It also examines the most suitable stabilization systems to protect the highly reactive and unstable molecules of natural pigments from negative physical and chemical changes, as well as to minimize the interactions with food systems.
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Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•Lecithin improved storage life and maintained quality of goji berries.•Postharvest decay and weight loss greatly reduced in lecithin treated fruits.•Lecithin enhanced the antioxidative potential of ...goji berries during storage.•All bioactive compounds positively effected in lecithin treated fruits.
To enhance storage life and post-storage quality of fresh goji berries, three treatments with lecithin (1, 5, 10g·L−1) and two storage times (8, 16days) were evaluated. The significant effects on the physiological and biochemical parameters were varied. 1g·L−1 lecithin showed its main effects after 8days of storage by reduction in total weight loss and decay, SSC/TA ratio (also at 16days), and chlorophyll content and with highest scores of sensory attributes (also at 16days). 5g·L−1 lecithin showed its main effects after 16days of storage: highest SSC, highest TA (also at 8days), highest TPC, only significant reduction in DPPH antioxidant activity, and highest total flavonoid content. 10g·L−1 lecithin showed its main effects after 8days of storage with highest SSC, chlorophyll content, total flavonoid, DPPH, and ABTS antioxidant activity (also at 16days), but with least scores of sensory attributes.
Summary There is a growing need for new formulations of carriers with better protection for bacterial inoculum. One of the newer techniques in inoculum making is encapsulation method. With this ...method, the whole bacterial cells are immobilized in defined space – matrix, where the cells are protected from environmental activities before use. Encapsulation of the inoculum was performed with ionic gelation method. The alginate-based microparticles (500-600 µm) containing viable B. japonicum strain were solidified in CaCl 2 . The initial number of viable bacteria in every sample was 9.0 log CFU/ml. Chitosan coated particles had a higher mortality rate than non-coated particles, with 1.3 log CFU/ml in lyophilized and wet microparticles stored at room temperature. High viability of B. japonicum was registered in wet particles stored at constant −20°C for thirty days with a viability rate of 8.84 log CFU/ml.
This review presents a critical analysis of food-grade delivery systems, which are suitable for the delivery of essential oils (EOs) for food applications. In particular, the main colloidal systems, ...investigated in vitro for the encapsulation of essential oils, such as nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers, carbohydrate-based carriers, protein-based carriers, liposomes and gelatin, have been described in details, with a special focus on their formulation, the type of oils encapsulated, and the fabrication processes, as well as on the resulting antimicrobial activity with respect to free oils. Currently, among these food-grade colloidal systems, only nanoemulsions, liposomes, and biopolymeric particles have found use in real foods, because of their easily-scalable production processes, loading capability with EOs, as well as cost-effectiveness. The main applications in foods are discussed, with reference to the possible methods of incorporation of encapsulated essential oils in foods, such as direct mixing, washing or infusion, and coating within active biopolymeric matrices. In addition, also the use of encapsulated essential oils in several other fields is presented, such as in organic farming, pest control or luring, as well as in pest-repellent textiles. Finally, the main regulatory issues are discussed.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•Tomato plants were treated with microspheres carrying chemical and biological agents.•Plants respond to microspheres and stimulate the synthesis of secondary metabolites.•Microspheres treatments ...significantly influenced metabolites synthesis in tomatoes.
Plant secondary metabolites play an important part in the human diet. This research investigated the effect of alginate microspheres loaded with chemical (calcium or copper ions) or chemical and biological (Trichoderma viride) agents on plant secondary metabolites synthesis of two tomato varieties ('Vasanta' and 'Abellus') in two types of greenhouse cultivation, hydroponic and soil. Targeted and controlled release of active agents facilitates the root of plants to respond to the encapsulated agents and stimulate the synthesis of investigated plant metabolites both in hydroponic and soil types of cultivation. A significant increase in lycopene (up to 230%), total polyphenols content (up to 61%), and the overall antioxidant activity (up to 77%) of the tomato fruits was found for all of the treatments, respectively. Encapsulated chemical and biological agents remarkably stimulate the synthesis of plant secondary metabolites in tomato fruits indicating its great potential in the production of value-added foods.
The impact of a cationic surfactant, dodecylammonium chloride (DDACl), on the self-assembly of sodium caseinate (SC) has been investigated by light scattering, zeta potential, and rheological ...measurements as well as by microscopy (transmission electron and confocal laser scanning microscopy). In SC dilute solutions concentration-dependent self-assembly proceeds through the formation of spherical associates and their aggregation into elongated structures composed of connected spheres. DDACl interacts with SC via its hydrophilic and hydrophobic groups, inducing changes in SC self-assembled structures. These changes strongly depend on the surfactant aggregation states (monomeric or micellar) as well as concentration ratio of both components, leading to the formation of soluble and insoluble complexes of nano- to microdimensions. DDACl monomers interact with SC self-assembled entities in a different way compared to their micelles. Surfactant monomers form soluble complexes (similar to surfactant mixed micelles) at lower SC concentration but insoluble gelatinous complexes at higher SC concentration. At surfactant micellar concentration soluble complexes with casein chains wrapped around surfactant micelles are formed. This study suggests that the use of proper cationic surfactant concentration will allow modification and control of structural changes of SC self-assembled entities.
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