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The aim of this study was to determine the total polyphenol and flavonoid content, antioxidant properties and fatty acid profile of semi-hard goat cheese ripened in an oil mixture (Mljet’s extra virgin olive oil and refined sunflower oil; 50:50) for different time periods. Five batches of cheese were produced, and each batch was divided into three groups: (1) ripening in air (control group), (2) ripening in oil after 10 days of air ripening, (3) ripening in oil after 20 days of air ripening. The cheeses were sampled on days 0, 10, 20, 30, 45 and 60 of ripening. On day 60, the total polyphenol and flavonoid content differed significantly (p

The layer-by-layer application of biopolymeric coatings to mandarin fruits as a postharvest treatment to improve fruit coating efficacy has been reported. A single 1 % (w/v) chitosan application was evaluated, and polyelectrolyte complexes such as 1.5 % (w/v) alginate/chitosan, 1 % (w/v) hydroxypropyl methylcellulose/chitosan, and 0.2 % (w/v) locust bean gum/chitosan were applied to mandarin fruits. The quality of coated mandarin fruits was observed at temperatures: 20 ± 2 °C (up to 10 days) and 5 °C (up to 28 days). Changes in the fruit metabolism were observed by evaluating bioactive compounds (polyphenolic compounds and flavonoids), antioxidant activity, and organic acids during the preservation of mandarin fruits. All of the tested combinations of layer-by-layer coatings significantly impacted the quality of mandarin fruits throughout storage, both at room temperature and cold storage, respectively. The overall best performance was observed for a layer-by-layer hydroxypropyl methylcellulose/chitosan coating in terms of visual aspects, bioactive compounds, antioxidant activity, and organic acids content.

Mandarins are the second most farmed citrus. Consumers demand a mandarin fruit that is both tasty and excellent in quality. The fruit quality, flavonoid profile, antioxidant capacity and total carotenoid content of five varieties (‘Zorica’, ‘Chahara’, ‘Kawano Wase’, ‘Owari’ and ‘Saigon’) of Satsuma mandarins grown in Neretva valley (Croatia) were determined. In this research, the distribution of bioactive compounds was different for mandarin juice, dry pulp residue and dry peels. Dry peels showed higher levels of polyphenolic compounds and antioxidant activity. Total carotenoids were found to be in a greater concentration in dry pulp residue than in the dry peel. The highest levels of total carotenoids (543 μg β-carotene/g) were found in the dry pulp residue of ‘Owari’ and ‘Saigon’, while the lowest levels were in ‘Chahara’ (227.87 μg β-carotene/g). In dry mandarin peels, the highest levels of total carotenoids were in ‘Kawano Wase’ (227.58 μg β-carotene/g), and the lowest levels were in ‘Chahara’ (52.24 μg β-carotene/g). The most abundant component of polymethoxyflavones (PMFs) in mandarin dry peel was nobiletin, ranging from 0.204 mg/g (‘Chahara’) to 0.608 mg/g (‘Saigon’), followed by tangeretin, ranging from 0.133 mg/g (‘Chahara’) to 0.251 mg/g (‘Saigon’), and sinesestin (‘Zorica’), ranging from 0.091 mg/g to 0.353 mg/g (‘Saigon’).

The development of antimicrobial polymers is a priority for engineers fighting microbial resistant strains. Silver ions and silver nanoparticles can assist in enhancing the antimicrobial properties of microcapsules that release such substances in time which prolongs the efficiency of antimicrobial effects. Therefore, this study aimed to functionalize different polymer surfaces with antimicrobial core/shell microcapsules. Microcapsules were made of sodium alginate in shell and filled with antimicrobial silver in their core prior to application on the surface of polymer materials by dip-coating methodology. Characterization of polymers after functionalization was performed by several spectroscopic and microscopic techniques. After the characterization of polymers before and after the functionalization, the release of the active substances was monitored in time. The obtained test results can help with the calculation on the minimal concentration of antimicrobial silver that is encapsulated to achieve the desired amounts of release over time.

Silver (Ag) and zinc (Zn) are very powerful antimicrobial metals. Therefore, in this research, a high-throughput, sensitive, and rapid method was developed for the determination of Ag and Zn in microcapsules using inductively coupled plasma mass spectrometry (ICP-MS). The sample preparation procedure employed simple microwave digestion of the microcapsules with 55.55% v/v HNO3 and 44.45% v/v H2O2. The method was applied to determine Ag and Zn in microcapsule samples of different sizes (120 and 450 μm) after their preparation with and without chitosan. Prepared microcapsules, after characterization, were bonded to a polymer carrier by sol-gel procedure and the materials were characterized by FTIR spectroscopy and high-resolution optical microscopy. Significant differences were found in Ag and Zn levels between microcapsules samples prepared with and without chitosan. The results have shown that samples with chitosan had up to 20% higher levels of Zn than Ag: 120 μm microcapsules contained 351.50 μg/g of Ag and 85.51 μg/g of Zn, respectively. In contrast, samples prepared without chitosan showed larger overall variability: In microcapsules with a diameter of 120 μm, the amounts of antimicrobial metals were 98.32 μg/g of Ag and 106.75 μg of Zn, respectively. Moreover, 450 μm microcapsules contained 190.98 μg/g of Ag and 121.35 μg/g of Zn. Those quantities are high enough for efficient antimicrobial activity of newly prepared microcapsules, enabling the application of microcapsules in different antimicrobial coatings.