Optimization of salt, olive oil and pectin level for low-fat frankfurters produced by replacing pork backfat with olive oil

Response surface methodology was used to determine the optimum salt level (1.3–2.1%) and pectin level (0.25–1.0%) when olive oil replaced pork backfat (0–100%) for the production of highly acceptable low-fat frankfurters (9% fat, 13% protein). The test ingredients significantly affected (P<0.05) jelly separation of the batter, skin strength, hardness, saltiness, odour and taste and the overall acceptability of the low-fat frankfurters. Batters with high pectin levels recorded the highest (P<0.05) jelly separation. Low-fat frankfurters with high salt levels tended to have very hard skins and increased (P<0.05) saltiness while those with a high pectin level were very soft, tasted like cream and had the lowest (P<0.05) score for odour and taste. The low-fat frankfurters with 1.8–2.1% salt, 0–35% olive oil and 0.25–0.45% pectin had the highest overall acceptability. However, low-fat frankfurters produced with 1.3% salt, 0.25–0.30% pectin and 80–100% olive oil were also acceptable. Such low-fat frankfurters, compared to commercial products, have a 48% lower salt content (from 2.5 to 1.3%) and 66.6% lower fat content (from 30 to 10%), in which 80–100% of the added fat is olive oil. Further research is needed to improve the acceptability of these frankfurters.