No abstract

Optimum conditions for high-quality gelatin recovery from camel skin and its molecular, structural, and rheological characterization were carried out in this study. Increased yield and gel strength were recorded, with an increase in camel skin pretreatment times of 6 to 42 h and 0.50 and 0.75 M-NaOH. Gelatin from skin pretreated with 0.75 and 0.5 M-NaOH for 42 h showed the highest yield (22.60%) and gel strength (365.5 g), respectively. Structural characterization by Fourier transformation infrared spectra, X-ray diffraction, and nuclear magnetic resonance indicated that all gelatins possessed major peaks in the amide region, and diffraction peaks around 22° were basically amorphous. The temperatures for gelling and melting ranged from 20.9 °C to 25.8 °C and 27.34 °C to 30.49 °C. Microstructure revealed loose network with more voids in gelatin from skin pretreated with 0.5 and 0.75 M-NaOH for 6 h, while a highly cross-linked network and less voids were observed in those pretreated with 0.75 M-NaOH for 24 h and 0.5 M-NaOH for 42 h. The results reveal that great potential exists in producing halal gelatin with excellent quality and functionality from camel skin.

In this study, the effects of gelatin films enriched with 2% of citrus (orange ([OSE] and lemon [LSE]) seed extracts (CSE) on the quality of sea bass (Dicentrarchus labrax) fillets during refrigerated storage (4 ± 1°C) for 15 days were determined. The results showed that lipid oxidation delayed in OSE and LSE groups compared with control and gelatin‐film (without extract)‐coated groups. According to microbial results, the addition of CSE enhanced the antimicrobial activity of gelatin films and, therefore, delayed the microbial growth. The incorporation of CSE with gelatin films showed a positive effect on the sensorial parameters of fillets. The shelf life of fillets was found as 6 days for the control, 9 days for GF group, and 12 days for both OSE and LSE groups. In conclusion, the supplementation of CSE raised the effectiveness of the gelatin films and can be recommended to maintain the quality of sea bass fillets. Practical applications Seafoods are highly perishable products and maintaining the quality of seafoods is a very important issue. As excessive citrus wastes are produced in the food industry, possible ways of their utilization are need to be searched. Citrus seed extract (CSE) was evaluated as natural antioxidant and antimicrobial agent in prolonging the shelf life of sea bass fillets in this study. The results revealed that CSE contributed to maintain the oxidative, microbiological, and sensory quality of sea bass fillets during storage. Thus, considering the consumers concerns about the synthetic ingredients, CSE can be suggested as a natural antioxidant and antimicrobial source in foods. Additionally, finding of this research could help to evaluate food wastes and the industrial usage of these products as a natural preservative.