Effect of replacing pork backfat with pre-emulsified olive oil on lipid fraction and sensory quality of Chorizo de Pamplona — a traditional Spanish fermented sausage

Six treatments of Chorizo de Pamplona, traditional Spanish fermented sausage, were manufactured under usual commercial conditions by replacing 0, 10, 15, 20, 25 and 30% of pork backfat by pre-emulsified olive oil with soy protein isolate. Sausages with 20–30% replacing level had higher (P<0.05) protein content than control as a result of the addition of soy protein isolate. The oleic acid increased (P<0.05) in sausages with 15–30% replacing level, and linoleic acid increased in sausages with 10–25%. Sausages with 10–25% of substitution had lower total SFA-stearic and higher (P<0.05) total MUFA, total PUFA, (MUFA+PUFA)/(SFA-stearic), and PUFA/(SFA-stearic). Cholesterol content showed reduction about 12–13% in sausages with 20–25% replacing level, and up to 22% in sausages with 30% replacing level. Sausages with 10–25% of substitution were acceptable from the sensorial point of view. The texture and colour instrumental measures were comparable with that of commercial products. No increments in hexanal content were observed. It is concluded that up to 25% of pork backfat can be replaced with pre-emulsified olive oil in the production of Chorizo de Pamplona fermented sausages. Higher replacing levels of pork backfat did not show nutritional advantages in relation to the fatty acid profile and were unacceptable due to considerable dripping of fat during ripening.