Effect of Treatment with Ultrasonic Pulses on the Functional Properties and Antioxidant Capacity of Dogfish (Galeorhinus galeus) Viscera Proteins

Document Type : Original Article

Authors

1 Department of Engineering, Faculty of Food Industry Engineering, National Institute of Technology of Mexico/Technological Institute of the Yaqui Valley

2 Department of Engineering, Faculty of Sustainable Agricultural Engineering, Food Industry Engineering, National Institute of Technology of Mexico/Technological Institute of the Yaqui Valley

3 Department of Crop and Animal Production, Safiye Cikrikcioglu Vocational College, Kayseri University, Kayseri, Turkey Genome and Stem Cell Research Center, Erciyes University, Kayseri, Turkey

4 Sonora Institute of Technology, Department of Biotechnology and Food Sciences, Ph.D. Program in Biotechnology. Center Unit

5 National Institute of Technology of Mexico/Technological Institute of the Yaqui Valley, Department of Engineering, Bacum, Sonora, Mexico

10.21608/ejabf.2025.428694.6712

Abstract

The valorization of fish by-products represents a sustainable strategy for obtaining high-value functional ingredients. The viscera of Galeorhinus galeus were evaluated as a source of protein hydrolysates with nutritional and bioactive potential. The objective was to determine the impact of ultrasonic pretreatment on proximate composition, antioxidant activity, and techno-functional properties of enzymatic hydrolysates. Viscera were subjected to autohydrolysis with and without ultrasonic pulses. Proximate composition was analyzed, antioxidant activity was assessed by DPPH and FRAP assays, and the degree of hydrolysis (DH) was quantified. Protein degradation was evaluated by SDS-PAGE, while foaming and emulsifying capacities were determined as indicators of functional performance. Ultrasound significantly improved protein solubilization, increasing DH to 28.4% compared with untreated controls. Antioxidant activity was enhanced, with ultrasound-treated hydrolysates reaching up to 97.8% radical inhibition at acidic pH and moderate hydrolysis times. Electrophoretic analysis confirmed progressive fragmentation into low-molecular-weight peptides, consistent with the observed increase in DH. Techno-functional evaluation showed a marked improvement in foaming capacity (from 24% to 97%), whereas emulsifying capacity decreased (<25%) due to disruption of amphipathic structures. These findings demonstrate that ultrasound-assisted hydrolysis enhances the nutritional, antioxidant, and techno-functional properties of shark viscera proteins. This approach provides a sustainable alternative for generating protein ingredients with potential applications in food formulations and nutraceutical development.

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