Ultrasound and Acid Pretreatments Boost Gelatin Yield from Milkfish Skin

Gelatin extracted from milkfish (Chanos chanos) skin performed best when ultrasound was combined with acid pretreatment, according to a study published in BMC Biotechnology. Researchers compared acetic acid pretreatment, a combined sulfuric acid–acetic acid pretreatment, ultrasound-assisted extraction, and an optimized multi-step extraction to see how processing choices shaped yield and gelatin quality.

Extraction conditions significantly affected both yield and functional properties. The highest yield, 42.63 ± 1.63%, came from ultrasound-assisted extraction paired with sulfuric acid and acetic acid pretreatment. Ultrasound treatment also improved the thermal and rheological behavior of the resulting gelatin, raising the melting temperature to 33.30 °C and the gelling temperature to 19.70 °C.

Gelatin produced with acetic acid pretreatment and ultrasound showed greater viscosity, at 11.92 cP, and a gel strength of 219.57 g, exceeding the values obtained through conventional extraction methods.

Color analysis of the extracted gelatin produced ΔE* values ranging from 55.37 to 59.19, which the authors report as indicating retention of the natural gelatin pigmentation. Overall, the study concluded that ultrasound-assisted extraction combined with an appropriate acid pretreatment enhanced gelatin yield and improved its physicochemical, thermal, and rheological characteristics.

Subject of Research: Extraction and characterization of gelatin from milkfish skin using different pretreatment and extraction methods

Article Title: Extraction, physicochemical, thermal, and rheological characterization of gelatin from milkfish (Chanos chanos) skin using different pretreatment and extraction methods

Article References: Barzkar, N., Lasiuan, V. P., & Jamain, A. H. M. B. (2026). Extraction, physicochemical, thermal, and rheological characterization of gelatin from milkfish (Chanos chanos) skin using different pretreatment and extraction methods. BMC Biotechnology. https://doi.org/10.1186/s12896-026-01236-9

Image Credits: AI Generated

DOI: 10.1186/s12896-026-01236-9

Keywords: gelatin, milkfish, Chanos chanos, ultrasound-assisted extraction, acid pretreatment, gel strength, viscosity, rheology, thermal properties, fish byproducts, Extraction, physicochemical