Quality improvement of pangasius fillets using aqueous seaweed (Padina tetrastromatica) extract

Meat discoloration and fat oxidation are the major quality issues in pangasius fillet during storage. In this study, aqueous seaweed extracts prepared from Padina tetrastromatica using three protocols were evaluated based on its total phenolic content and antioxidant activities. Based on the ideal result, different concentration of seaweed extracts ranging from 0.5 to 2% (v/v) were used for dipping the pangasius fillet. Individual fillet samples were packed stored under chilled condition (2 degrees C). Among the quality parameters proximate composition, total volatile basic nitrogen, free fatty acids, thiobarbituric acid reactant substances, myoglobin content, aerobic plate count, instrumental colour and sensory analysis were carried out at regular intervals of 4 days. Seaweed extract containing phenolics reduced the myoglobin oxidation which is positively correlated with redness values. Among the different treatments 2% aqueous extract showed reduction in total volatile basic nitrogen, rancidity, total bacterial count, sensory quality parameters and effectively reduced the spoilage and meat discoloration of fillet up to 20 days. It can be concluded that aqueous seaweed extract can be used as a natural additive for improving meat colour and extending the storage life of fishery products under chilled conditions.

Automated summary

The study found that seaweed extract rich in phenolic substances can reduce myoglobin oxidation in pangasius fillet, which is positively correlated with redness values. Among the different treatments, the 2% aqueous seaweed extract showed a reduction in total volatile basic nitrogen, rancidity, total bacterial count, and sensory quality parameters, effectively extending the spoilage and discoloration of the fillet for up to 20 days.