Radical scavenging properties of protein hydrolysates from Jumbo flying squid (Dosidicus eschrichitii Steenstrup) skin gelatin

Gelatin extracted from Jumbo flying squid skin was hydrolyzed with serials of protease. The scavenging effects of gelatin hydrolysates on superoxide and hydroxyl radical were assessed by chemiluminescence analysis. Properase E and pepsin have shown efficient hydrolysis of squid skin gelatin to obtain high radical scavenging activity peptides. The conditions chosen for enzymic hydrolysis of squid skin gelatin with properase E were pH 9.0, 45 °C, 3 h reaction time, and enzyme‐to‐substrate ratio of 1:50. Hydrolysates combining properase E and pepsin showed the best radical scavenging activity. For fragmented hydrolysates by ultrafiltration, fractions UF‐2 (Mw < 2000 Da) had high yield and radical scavenging activity.