Zein or gelatin nanofibers loaded with au nanospheres, SnO2 or black elderberry extract used as active and smart packaging layers for various fish fillets ; Altın nanokürecikleri, SnO2 veya kara mürver ekstresi ile yüklenen zein ve jelatin nanoliflerinin farklı balık filetoları için aktif ve akıllı ambalaj katmanı olarak kullanılması

Thesis(Ph.D.) -- Istanbul Technical University, Graduate School, 2022 ; Fresh fish products spoil in a shorter time than other meat products. Consumers would prefer the freshest fish products that have higher initial quality. Therefore, it is important to investigate alternative methods to preserve the quality of fresh fish products and increase their shelf life. Furthermore, estimating the shelf life of fresh fish products in fast and easy methods has started to gain importance in recent years. These developments increase researchers' interest in active and smart packaging layers that are produced by nanotechnological methods. In this dissertation preparation, characterization, and practical application of biopolymer-based electrospun nanofibers as active and smart packaging layers are presented. First, the purpose and objectives are explained and recent studies are presented in Chapter l. Then, preliminary microbiological analyzes were applied to smoked fish products after their packages being opened (Chapter 2), suggesting that the smoking process inhibit microbial growth only if the package is not being opened. Then, the quality of three different fish meat samples (local salmon: YS, bream: Ç, sea bass: L) was determined in terms of the electrical conductivity value, surface tension values, and the ε″. Sensory evaluation results were also evaluated by photos and point scales. The electrical conductivity value of the YS, Ç, and L samples on the initial day (0.21, 0.24, and 0.233 mS cm-1) increased on the 4th day of storage (0.35, 0.39, and 0.47 mS cm-1), respectively (~65%, 63%, and 101% change). Dielectric loss factor values calculated at a frequency of 30 MHz were also increased with the highest change of L samples (29.68%) on the 4th day. On the contrary, surface tension values decreased with storage time. The surface tension of YS, Ç, L, declined from 38.22, 42.56, 37.57 mN m-1 to 16.2, 29.45, 25.94 mN m-1 on the 2nd day of storage. Results revealed these analyzes can be accepted as an important and rapid ...