Properties of Fish Sausages Containing Common Carp (Cyprinus carpio) Roe Oil and Defatted Roe Protein Hydrolysate during Refrigerated Storage

Influence of emulsified or non-emulsified common carp roe oil (CRO) and carp defatted roe hydrolysate (CDRH) on properties of crucian carp (Carassius auratus) sausages was determined during 30-day storage at 4 degrees C. Sausages containing CRO and CDRH were lighter and had better textural properties including hardness, gumminess, and chewiness. These textural attributes were significantly higher in the sample prepared with pre-emulsified CRO and 7g/100g CDRH (p<0.05). The sausages fortified with CDRH also presented better microstructure, as evidenced by fewer voids and smaller oil droplets. When incorporated at 7g/100g, CDRH could significantly reduce microbial spoilage in sausages in terms of the total viable count and the psychrophilic bacterial count (p<0.05); however, pre-emulsification had no significant effect on antibacterial activity of hydrolysate in the samples (p>0.05). Sausages with pre-emulsified roe oil and 7g/100g hydrolysate were more resistant against lipid oxidation and had a higher level of polyunsaturated fatty acids, especially docosahexaenoic acid and eicosapentaenoic acid after 30days of storage at 4 degrees C. Furthermore, the sausages with pre-emulsified CRO and 7g/100g CDRH exhibited better organoleptic properties at day 30.