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A study of 10 herbhoneys of various origin revealed differences in their antioxidant activity and profiles of phenolic acids and flavonoids. The total phenolic content of herbhoneys determined spectrophotometrically varied between 21.7 and 75.3mg gallic acid equivalents per 100g product, and the total flavonoid content ranged from 6.9 to 28.5mg quercetin equivalents per 100g. Dark herbhoneys, such as raspberry, thyme, hawthorn and black chokeberry, exhibited a high antioxidant activity and contained high total levels of polyphenols and flavonoids. There was a significant linear correlation between total phenolic and flavonoid contents and antioxidant activity in the reactions with DPPH· and ABTS·+ free radicals. The profiles of phenolic acids and flavonoids determined by HPLC depended on the variety of herbhoney. Among the products studied, raspberry and thyme herbhoneys were the richest in phenolic acids and flavonoids. The dominant phenolic acid in most samples was p-coumaric acid; the herbhoneys contained also a considerable amount of gentisic acid. The dominant flavonoids were hesperetin and naringenin. Thyme herbhoney had an especially high quercetin content. [Copyright &y& Elsevier]

Abstract: Herbhoney is a honey-like substance produced by bees fed on a saccharose-based food supplemented with herbal extracts or fruit juices. Having specific sensory characteristics (colour, aroma and taste), different from those of natural honeys, herbhoneys greatly extend the range of bee products. With the aim of improving the knowledge of herbhoneys of various origins, their chosen physicochemical and quality parameters were evaluated. It was found that the herbhoneys studied satisfied most of the requirements relative to natural honeys (water, hydroxymethylfurfural and saccharose contents, free acidity, and diastase number). Some of the samples showed an increased specific conductivity, characteristic of honeydew honeys, although the ash contents of herbhoneys were at a level typical of nectar honeys. The saccharose content of some herbhoneys exceeded the value allowed for most natural honeys. Mineral composition varied between the samples, being in most cases within the limits reported in this literature for natural honeys. [Copyright &y& Elsevier]

• Multi-layer films were developed on the basis of furcellaran. • The added film additives are an element of activities aimed at improving quality and gave the films active properties. • Storing fish in the created films demonstrated better microbiological parameters. To improve the quality of multi-layer film, four-layer films based on furcellaran and active ingredients: gelatin hydrolysate, curcumin, capsaicin, montmorillonite and AgNPs, were produced in an innovative manner. The films were characterised by SEM and AFM analysis. Along with an increase in the concentration of active ingredients, the structure of the film becomes less homogeneous, which may affect the functional properties. The objective of the study was to analyse changes in the functional properties of the newly-obtained films and to verify their potential as packaging materials for fish products. With the increase in active ingredient concentration, water properties also improved, but there were no noticeable significant effects on mechanical properties. For antioxidant properties, the obtained values were within 1.04–2.74 mM Trolox/mg (FRAP) and 7.67–40.49% (DPPH). The obtained multi-layer films were examined with regard to the shelf-life of salmon. For this purpose, salmon fillets were packed in films having good antioxidant and functional properties. The films were effective in microorganism growth inhibition responsible for fillet spoilage during storage. The microorganism number in the active film-stored samples was lower by 0.13 log CFU/g on day 12 versus the control. However, film application did not retard lipid oxidation in the salmon fillets. Nonetheless, the films show great potential as active packaging materials, extending the shelf-life of the packed foods. [ABSTRACT FROM AUTHOR]

• Double-layer films with aqueous extract of clitoria flower (BP) were prepared. • Double-layer film showed strong antimicrobial and antioxidant activity. • BP enhanced UV-barrier of double-layer films and give them intelligent activity. • The wrapped fish showed better microbiological parameters and low lipid oxidation. Innovative, intelligent and active double-layer films, based on furcellaran and with the addition of gelatin hydrolysates, have been obtained for the first time. An aqueous extract of clitoria flower in 3 concentrations was included in the 1st FUR layer. The films demonstrated strong antimicrobial effects, but did not exhibit fungicidal properties. The antioxidant properties of the films were within the range of 2.27–3.92 mM Trolox/mg (FRAP method) and 36.67–61.24 % (DPPH method). The films were used as active packaging materials in salmon fillets, which were stored for a period of 12 days in 4 °C. Analysis concerning microbiological properties of the stored fillets showed the possibility of extending their shelf-life by 6 days. Lipid oxidation, determined by TBARS has delayed. The obtained films are a promising material for the packaging industry. This is an important aspect within the context of global food waste and also the need to reduce synthetic materials. [ABSTRACT FROM AUTHOR]

This study was aimed at determining the effect of starch oxidation on its acetylation, structure of starch granules, and generation of free radicals. Corn and waxy corn starches were oxidised by NaClO applied in doses of 10, 20, and 30 g Cl/kg of starch, and then acetylated using acetic acid anhydride. The carboxyl, carbonyl, acetyl groups were determined in modified starches. Structural properties of starch granules were evaluated based on molecular weight distribution, gelatinisation, crystallinity, specific surface, intrinsic viscosity. EPR measurements were carried out to establish starch susceptibility to UV irradiation induced generation of free radicals. It was found that the number of carbon centered radicals was dependent on the kind of starch and its chemical modification. Study results allowed concluding that the applied modifications contributed to significant changes in starch granules that were determined not only by the amylose content of starch but also by the degree of its oxidation. [ABSTRACT FROM AUTHOR]

• Triple-layered films were successfully prepared using the solution casting method. • The prepared films had improved UV–vis barrier properties and antioxidant activity. • The color of the film responded to pH change. • The films improved the storage quality of tomatoes. Triple-layered, pH-sensitive and active films based on furcellaran (FUR), chitosan (CHIT) and gelatin hydrolysates (HGEL) were obtained for the first time. Curcumin ethanol extract (CUR) enriched with lemongrass essential oil (LEO) in three concentrations was added to the middle layer of the film. SEM and AFM analysis confirmed the formation of 3 layers, and CUR-LEO was evenly dispersed in the 2nd layer. The addition of CUR-LEO influenced the color of the surface and improved the UV blocking properties of the film. However, the mechanical and water vapor barrier properties remained unchanged. The CUR-LEO demonstrated antibacterial properties against bacteria and fungi. The antioxidant activity of the films increased along with the increasing concentrations of CUR-LEO. The presented films were able to effectively extend the storage life of tomatoes. Moreover, the colored films had the monitoring freshness effect with a distinct color change during carp storage. [ABSTRACT FROM AUTHOR]

• Extract from soybean bran has been added to the 1st layer of furcellaran films. • Double-layer and single-layer active films can act as a substitute for plastic. • The active films extended the shelf-life of butter. Single-layered films, based on furcellaran and protein hydrolysates from soybean bran (1st layer), were obtained. Moreover, a procedure for the preparation of double-layered films was developed, in which an ethanol extract from soybean bran was deposited onto the 1st layer. It was checked how the addition of the 2nd layer affects the functional properties of the film. The addition of the 2nd layer increased the thermal properties, modulus of elasticity and antioxidant activity, while decreases were noted for tensile strength and elongation at break parameters. The films were used as packaging materials for storing butter and the active films did not extend the quality of butter during storage, however, they behaved in the same way as synthetic films. Therefore they have the potential to be used as packaging material instead of a synthetic film. [ABSTRACT FROM AUTHOR]

• The double-layer furcellaran/gelatin hydrolysate and Ala-Tyr dipeptide film were developed. • The addition of peptide improved antioxidant and properties of the film. • The properties of films were tested on fish carcasses during frozen storage. • The application of films on the fish did not significantly inhibit oxidation rate. This is the first time that active double-layered furcellaran/gelatin hydrolysate films containing Ala-Tyr peptide were developed and characterised for their properties. Afterwards, films were used on Atlantic mackerel stored at −18 °C for 4 months and samples were analysed for changes in their microbiological quality, TVB-N, biogenic amine content, fatty acid composition and TBARS. Active films had higher TS (13.4 MPa) and lower WS (62.8%). The films showed no DPPH radical scavenging properties but high FRAP (6.6 mMol Trolox/mg). No significant effects on the oxidation of fish samples were observed with TBARS increasing from 12.04 to 22.50 mg/kg. Freezing successfully inhibited the growth of microorganisms and no differences in microbiological growth or biogenic amine formation were observed. However, the application of films inhibited the formation of TVB-N. Antimicrobiological properties of the film should be further investigated during storage of perishable food products at temperatures above 0 °C. [ABSTRACT FROM AUTHOR]