Ultrasound assisted treatment improves the preservation performance of chitosan‐grafted‐chlorogenic acid on refrigerated sea bass (Lateolabrax japonicus) fillets

Abstract

Background Ultrasound can increase the mass transfer between preservatives and food, and enhances the effect of preservatives on food. Chitosan‐grafted‐chlorogenic acid (CS‐g‐CA) is a new synthetic compound with good antiseptic properties. Therefore, the present study evaluated the preservation performance of ultrasound‐assisted CS‐g‐CA (GUA) coatings on refrigerated sea bass fillets in terms of changes in microorganisms, lipids, proteins, tissue structures, and moisture. Results The results showed that GUA treatment effectively inhibited the growth of microorganisms in sea bass fillets. Meanwhile, the changes in total volatile basal nitrogen, thiobarbituric acid reactive substances, and pH values were all slowed down under GUA treatment, indicating that protein degradation and lipid oxidation in sea bass were inhibited. Low‐field nuclear magnetic resonance and magnetic resonance imaging results indicated that the GUA retarded the conversion of mobile water to free water. In addition, GUA treatment maintained the flavor quality of fish fillets, and also inhibited the reduction of inosine monophosphate and the production of bitter substances (inosine and hypoxanthine), suppressed muscle tissue degeneration, and maintained better sensory scores. Conclusion Overall, GUA treatment inhibited microbial growth, protein degradation, lipid oxidation, moisture migration, decomposition of umami substances, and deterioration of sensory quality in sea bass fillets. Finally, the shelf‐life of sea bass fillets with GUA treatment was extended by an additional 9 days. The results showed that ultrasonic assistance further enhanced the effect of preservatives on aquatic products. © 2022 Society of Chemical Industry.

Ultrasound‐assisted chlorogenic acid‐grafted chitosan soaking of sea bass (Lateolabrax japonicus) fillets to reduce protein oxidation and maintain gel properties

“…The preparation of CS‐g‐chlorogenic acid by carbodiimide coupling was carried out with reference to previous studies, and the procedure was followed by Yang et al (2023). Briefly, configure 125 mL of CS solution (6.1 g, dissolved in 2% acetic acid, solution 1, 0.302 mol/L), 25 mL of CA solution (6.7 g, dissolved in ethanol, solution 2, 0.756 mol/L) and 50 mL of a mixture of L1‐(3‐dimethylaminopropyl)‐3‐ethylcarbodiimide hydrochloride (EDC, 7.2 g) and 4‐morpholineethanesulfonic acid (MES, 4.3 g) (solution 3), respectively.…”

“…The distribution and migration of water in protein gels were measured by LF‐NMR and MRI analyzer (NMI20‐060H, Niumag Analytical Instrument Corporation, Suzhou, China) with MSE imaging sequences referred to previous research (Yang et al, 2023). Briefly, the gel was cut into small squares (10 mm × 10 mm× 10 mm), and wrapped with a layer of polyethylene film to inhibit water evaporation during the measurement.…”

“…The distribution and migration of water in protein gels were measured by LF-NMR and MRI analyzer (NMI20-060H, Niumag Analytical Instrument Corporation, Suzhou, China) with MSE imaging sequences referred to previous research (Yang et al, 2023). Briefly, the gel was…”

“…In addition, several studies have shown that ultrasound has a positive effect on protein gel strengthening, which can induce protein structural changes (Qin et al, 2017). Recent studies have demonstrated that ultrasound can further improve the preservation effect of CS‐g‐CA on sea bass fillets (Yang et al, 2023). However, the effects of ultrasound‐assisted chitosan‐grafted‐chlorogenic acid (CS‐g‐CA) soaking of aquatic products on protein oxidation and gelation properties have not been investigated.…”