Production of fish-protein products (surimi) from small pelagic fish (Sardinops pilchardusts), underutilized by the industry

A sardine surimi product was studied, based on three experimental factors: (a) control of pH-value (2 levels) (b) improvement of protein solubility (2 levels) and (c) cryoprotectants (3 levels). Samples were frozen at −20 °C and kept at this temperature for 25 days. All samples were then partially thawed, mixed with 2 g kg−1 sodium chloride and heated at 90 °C for 90 min. The combination of sorbitol (40 g kg−1) with the salt mixture (sodium chloride 0.45 g kg−1 calcium chloride 0.3 g kg−1 and ammonium chloride 1.25 g kg−1) led to the hardest and more elastic products. Protein loss during the processes was relatively small (6.9% on a dry weight basis), and its solubility remained at high levels. The overall product recovery was 200 g kg−1. The use of different batches led in statistically significant differences among the final products. The concentration of eicosapentaenoic and docosahexaenoic fatty acids showed that under-utilized sardine could be an important source of polyunsaturated fatty acids and MaxEPA products.