Search

The aim of the study was to investigate the antioxidant and antimicrobial properties of novel, edible biopolymer coatings consisting of chitosan, furcellaran, carp skin gelatin hydrolysate and 8 different bioactive peptides: Lfcin-β, MBP-1, PLGG, LL37, Cys-LL37, melittin, RW4 and nisin. In vitro analyses consisted of evaluating FRAP and ABTS radical scavenging properties as well as effectiveness against various food pathogens. Consequently, the coatings were used to investigate their antimicrobial effect during cold storage of smoked pork ham dipped into the coating solutions with and without the presence of CaCl 2. Finally, the 2 most effective coatings were applied onto fresh cold stored pork loins with different doses of the investigated peptides (1.25–10 μg/mL). The biopolymer matrix had high radical scavenging properties (76.94%) and FRAP value (5.41 μmol of Trolox/mL), however, the antioxidant power was reduced when peptides were included. The coatings with peptides inhibited the growth of all tested food pathogens aside from Aspergillus flavus. They successfully inhibited the growth of total viable counts (TVC) with reductions even above 3.5 log cfu/g. The inclusion of CaCl 2 provided contradictory results for different groups and it was impossible to confirm its effectiveness. Coatings with RW4 and LL37 were selected as the most promising and proved effective in inhibiting the TVC of fresh pork loin, even at doses of 1.25–2.5 μg/mL. The newly developed coatings exhibit high antioxidant and antimicrobial power and could be used to effectively extend the shelf-life of perishable meat products. • Chitosan/furcellaran/gelatin hydrolysate/bioactive peptides coatings were developed. • Coatings exhibit high antioxidant and antimicrobial properties. • Antimicrobial properties were investigated both in vitro and on model food product. • Coatings with RW4 and LL-37 peptides had highest antimicrobial and antioxidant power. • Coatings effectively inhibited microbial growth on stored pork ham and pork loin. [ABSTRACT FROM AUTHOR]

The biological activity of furcellaran (FUR) and chitosan (CHIT) multi-layer micro/nanoemulsions with plant essential oils (EO) of oregano, lemongrass, thyme and rosemary (0.6nullμL/mL) and bioactive peptides (RW4 and LL37) applied on pork loins was evaluated along with consumer acceptance of the technology. Firstly, the emulsions were applied on pork loins via the electrospraying method using 3 layers of emulsions: (I):CHIT-EO, (II):FUR-EO and (III):CHIT-EO. The pork loins were stored for 11 days at 4 °C and analyzed for their total viable counts. All emulsion systems successfully inhibited the microbial growth, however, emulsions with oregano EO, both with and without peptides, were the most effective (inhibition by 3.25–4.08 cfu/g). Additional consumer analysis showed that consumers could not distinguish to which samples the coatings were applied and the Just About Right analysis allowed to indicated that gloss of coated samples was closer to ideal. Afterwards, in vitro antimicrobial analysis on 8 food pathogens and antioxidant analyses with FRAP, DPPH and metal chelating assays were performed on emulsions with oregano EO. The analyses demonstrated that CHIT emulsions have high antimicrobial potential against all the tested pathogens (complete inhibition at 1.6–50.0% of emulsion concentration). FUR emulsions showed much lower to no antimicrobial properties, depending on pathogen. The emulsions exhibited high antioxidant power measured through FRAP (8.84–12.17 μM Trolox/mL) and DPPH (40.0–82.8%) assays, however, almost no metal chelating properties (0.04–11.56%). The developed multi-layer emulsions with oregano EO have high biological activity and application potential for use on perishable food products, such as fresh meat. • Developed multilayer FUR/CHIT nano/microemulsions with plant EO and bioactive peptides. • 3-layer emulsions successfully inhibit native meat microflora growth on pork loin. • Emulsions exhibit potent antioxidant and antimicrobial properties against pathogens. • Consumer acceptance of the technology is high. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop novel antimicrobial coatings which could be used for extending the microbiological quality of perishable food products. Seven different antimicrobial peptides (Lfcinβ, PLGG, MBP-1, LL-37, Cys-LL-37, RW4 and melittin) have been investigated as possible agents for implementation into the previously developed chitosan/furcellaran (CHIT/FUR) coatings. The study included several steps of microbiological analysis, starting with minimum inhibitory concentration (MIC) analysis of crude peptide solutions (concentration from 0.78 to 100 μg/mL) against selected pathogens. The analysis showed that only RW4 and melittin proved effective against all studied pathogens in the investigated doses, except for Aspergillus flavus. The second examination included in-vitro analysis regarding antimicrobial activity of developed coatings with peptides at a concentration of 5 μg/mL, against chosen pathogens. This analysis allowed to indicate a complementary effect of antimicrobial activity between all peptides and the CHIT/FUR complex since the coatings inhibited the growth of the tested pathogens. Afterwards, the coatings were used to coat smoked pork ham slices stored for 10 days and analysed for the increase in total viable counts (TVC). The analysis demonstrated a high efficiency of the CHIT/FUR complex, even without the addition of peptides. Only RW4 and LL-37 did not cause a decrease in antimicrobial power of the control coating. Therefore, in the final trial, the effect of different doses (1.25–10 μg/mL) of RW4 and LL-37 peptides on the TVC of cold-stored coated pork loins. The coatings almost completely inhibited the increase of TVC in the pork loins and the peptides were effective at all studied doses. The newly-developed coatings had strong antimicrobial properties and can be used to extend the shelf-life of perishable food products. • Antimicrobial chitosan/furcellaran coatings with bioactive peptides were developed. • Antimicrobial properties were investigated both in vitro and in vivo. • Bioactive peptides addition improved the efficiency against food pathogens. • Coatings inhibited completely the total viable counts of stored pork ham and pork loin. • RW4 and LL-37 peptides were selected as the most efficient. [ABSTRACT FROM AUTHOR]