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This study originally reports the preparation and characterization of electrospun films based on poly(ε-caprolactone) (PCL) with high histamine-binding capacity. To this end, submicron PCL fibers filled with nanostructured zeolite or silica (SiO2) microparticles in the 5-20 wt% range were first prepared by electrospinning. The resultant electrospun composite fiber mats were thereafter thermally post-treated at 55 °C to successfully develop contact-transparent films with reduced porosity and improved mechanical strength. The capacity of the developed composite films to entrap histamine was evaluated in vitro by the culture media method using Staphylococcus aureus (S. aureus) and Salmonella Paratyphi A (S. Paratyphi A) food-borne bacteria. Both electrospun zeoliteand SiO2-containing PCL films exhibited high histamine-binding capacity, being more effective for S. aureus. The histamine entrapment performance was significantly higher for the PCL films filled with zeolite due to the enhanced porous structure and more optimal adsorption selectivity of this mineral. The here-developed electrospun composite films can be originally applied as novel activescavenging packaging materials to entrap heat-stable histamine and other biogenic amines released from fish and fishery products.

Animal derived proteins provide the essential amino acid requirements of a healthy diet. Among animal proteins, fish proteins have a well-balanced amino acid composition that are imperative for beneficial synthesizing and utilizing proteins in the body. Lack or low levels of any amino acid reduce the other amino acid utilization proportionately. This is why plant-derived proteins are potentially at a disadvantage for use in the body since they have relatively low levels of the essential amino acids methionine and lysine. Health studies have revealed that fish protein is suggested as a weight-loss diet to obese patients.

A protein-based electrospun nanofiber from cold water fish gelatin (FG) including bovine lactoferrin (L) as an antimicrobial substance for food packaging applications was developed. Various amounts of L (0, 5, 10, 15, and 20%) were incorporated into FG electrospun nanofibers in order to test antimicrobial activity by disc diffusion method against Pseudomonas fluorescens, Acinetobacter johnsonii, Aeromonas hydrophila, Flavobacterium psychrophilum, Shewanella putrefaciens, and Escherichia coli commonly cause problems in food safety especially in fish products. It was obviously seen that 15% and 20% wt L incorporated FG electrospun nanofibers had significant inhibition zone against all bacterial strains while 5% and 10% L-FG had lower antimicrobial effects. In order to recommend fish gelatin as a food packaging material, mechanical properties should be enhanced to be competitive with synthetic polymers. It was revealed that mechanical strength of gelatin electrospun nanofibers depended on both fiber morphology and bioactive substance content. Neat FG (N-FG ) bead-free electrospun mats had higher fiber diameter (815 ±40 nm) while 15% and 20% L-FG had relatively lower diameter with beaded morphology, i.e., 348 ±32 nm, 229 ± 44 nm respectively. The tensile strength of 20% L-FG mats was significantly lower than the N-FG mats due to beady and thinner morphology. It can be concluded that L-FG electrospun nanofibers with high antimicrobial activity and improvable tensile strength is promising for active packaging applications.Keywords: Electrospinning, Pseudomonas spp., Escherichia coli, Shewanella spp., biodegradable, active packaging

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In this research, with the aim of maximizing amino acid content by different hydrolization procedures of fish meat were carried out and analysed with high performance liquid chromatography (HPLC) equipped with diode array detector (DAD). Response surface methodology (RSM) was used to determine factors that used in the experiments. The RSM suggested 16 different hydrolization trials between the ranges of normality as 3 N - 8 N, temperature as 90°C-110°C and duration as 12-24 hours were run. In the following, hydrolysed samples were analysed with HPLC-DAD and obtained data were evaluated with Box-Behnken method in RSM. Our results show that, the most effective experiment was found as hydrolysing by 3.79 N at 110°C in 24 hours for total amino acid content as well as maximized essential amino acids with 0.981 desirability. For sensitive ones, hydrolysing in 3.42 N at 106.8°C in 12.02 hours was found as most effective with maximized Asn, Gln and Trp with 0.849 desirability.

Cold marinated foods are semi-preserve and not fully fermented products. However, when the fermented products such as vinegar are added to the process, lactic acid bacteria may develop in the medium. The aim of the study was to determine the presence of lactic acid bacteria associated with the spoiled vinegar-marinated anchovy. A total of 12 bacterial strains were isolated from this product. They were identified to species level using 16S rRNA gene sequence analysis. Lactobacillus paracasei subsp. paracasei and Lactobacillus curvatus were the two main species determined. This is the first report on the isolation of the lactic acid bacteria in marinated anchovy prepared with persimmon vinegar.