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The objective of this study was to produce encapsulated protein hydrolysates from Whitemouth croaker (Micropogonias furnieri) muscle and its industrialization byproduct. The protein hydrolysates were prepared from the muscle (MPH) and byproduct (BPH) from croaker by enzymatic hydrolysis using Flavourzyme Ò. The hydrolysates were encapsulated using phosphatidylcholine as the wall material of the capsules. The capsules were evaluated for particle size, polydispersity, encapsulation efficiency, zeta potential, morphology, thermal properties, Fourier transform infrared (FTIR) spectroscopy and antioxidant activity. The average size of the capsules for both MPH and BPH liposomes range between 266 and 263 nm with low polydispersity. The capsules showed high encapsulation efficiency of around 80%. The FTIR analysis allowed suggesting that there was an effective ionic complexation between phosphatidylcholine and hydrolysate peptides. The antioxidant activity of the hydrolysates and capsules containing MPH and BPH was similar to the activity of a-tocoferol, but lower than that of vitamin C.

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22This study evaluated the effect of protein hydrolysate (PH) and clove essential oil (CEO) on 23 agar film properties and the shelf-life improvement of flounder fillets. Firstly, Argentine croaker 24 muscle protein was alkali-solubilised and recovered to obtain a stable substrate. This substrate 25 was hydrolysed to 20% degree of hydrolysis, by Alcalase (A20) and Protamex (P20). The 26 molecular weight (MW) distribution, amino acid and in vitro antimicrobial activity of these 27 hydrolysates were tested. Agar films were prepared with and without (control) incorporation of 28 PH (A20 hydrolysate) or CEO characterised by mechanical properties, water vapour 29 permeability, solubility and optical properties. The microbiological, physical and chemical 30properties of flounder fillets coated with these films were monitored during storage at 5°C for 31 15 days. Compared to P20, A20 hydrolysate possessed lower MW, higher hydrophobic amino 32 acid content and the most effective antimicrobial activity against selected pathogens, such as 33 Staphylococcus aureus, Yersinia enterocolitica, Aeromonas hydrophila, Debaryomyces hansenii 34and Listeria innocua. The presence of PH increased the water solubility, water vapour 35 permeability, elongation at break and yellowness of the films. The CEO films possessed less 36 transparency than PH films and control films, due to the presence of oil in the formulations. 37Fillets covered with PH and CEO films, especially the latter, presented lower total volatile bases 38and pH values, and delayed considerably the growth of H 2 S-producing microorganisms 39 compared to the control films. The CEO might be used as a natural biopreservative to extend the 40 flounder shelf-life. However, further studies are necessary, to assess the antimicrobial effect of 41 PH when used as food packaging. 42 43

22Antimicrobial, anti-inflammatory antioxidant activities of protein hydrolysates from 23 Argentine croaker (Umbrina canosai) isolated (CPI) or Argentine croaker myofibrillar 24 protein (CMP) with different degrees of hydrolysis (DH: 10-20%) prepared using 25 Alcalase or Protamex were determined. Results showed that an increase in the DH 26 resulted in higher content of hydrophobic and aromatic amino acids and in a decrease in 27 molecular weight (MW) distribution for all hydrolysates obtained. Furthermore, the 28 enzyme and raw material used influenced the amino acid content and MW determined. 29 Hydrolysates from CPI with a 20% DH by Alcalase had higher ABTS radical 30 scavenging activity, metal chelation and ferric reducing antioxidant power-FRAP (p < 31 0.05). All hydrolysates samples decrease the pro-inflammatory capacity. In all the 32 evaluated microorganisms, only 7 were inhibited, most being Gram-positive. Alcalase 33 was found to exert a considerable influence on antibacterial activity. These hydrolysates 34 are an alternative as natural antimicrobials, anti-inflammatory and antioxidants 35 compounds. 36 37

The aim of this study was to investigate the use of protein-phenolic based coating made from fermented rice bran on cherry tomatoes (Lycopersicum esculentum). Tests were performed with glycerol 3% (v/v), glycerol with protein-phenolic rice bran extract (5%), glycerol with protein-phenolic extract after 96 hours of fermentation (5%), and a control (without coating). The coated cherry tomatoes were kept at room temperature for 28 days. Mass loss, pH and acidity, total soluble solids, and carotenoids were determined every 96 hours. The coating made from the biomass extract reduced the carotenoid and acidity levels in the fruits studied by 17 and 21.1%, respectively, compared to the control. The coating proved an efficient barrier to water vapor with mass loss of 57% less than the control suggesting that it can be used as an alternative for vegetable tissue conservation.

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