Significance of lipids in fermented meat technology

Abstract

English: Salami is a high fat content (30-50 %) meat delicacy produced by different sectors of the economy, i.e. household, cottage industries, butcheries and big enterprises. The composition of the product is varied, and salami usually hangs in butcheries or is stored in display cabinets. Because of the high fat content of the product, salami is as a result prone to spoilage due to temperature abuse. The lack of uniformity in storage conditions of salami has necessitated a study to establish the most suitable storage temperature for South African salami, based on the detectable changes in the lipid fraction of the product. A typical South African salami was manufactured, processed to maturation and stored at three temperatures, namely 4, 12 and 25°C for 15 to 30 days. Lipid hydrolysis and oxidation were significantly high at the 25 °c, moderate at 12°C and minimal at the 4 0c. This implied that, based on the changes in the lipid fraction of salami, 4 °c is an excellent temperature, 12°C is satisfactory and the most practical, while 25 "c in unacceptable for storage of South African salami. The 12°C storage temperature was used to establish the effect of high dietary PUF A on the lipid stability of salami. Higher PUFA levels adversely affected lipid hydrolysis and oxidation, implying that typical South African pig finishing diet supplemented with 3 % sunflower oil (corresponding to 57.88 ± 0.65 and 30.03 ± 4.53 PUFA levels for feed and backfat respectively) may compromise the keeping quality of salami. In an effort to diversify salami production, the viability of replacing pork backfat with ostrich and sheeptail fat in salami manufacture was assessed. Ostrich fat is rich in PUF A; sheeptail fat is more saturated while pork backfat fatty acid composition is intermediate between the two, a factor that was reflected in the salami manufactured from these fat sources. Lipid hydrolysis was significantly higher in the sheeptail fat salami, although no significant differences were observed in the build-up of peroxides. The pork backfat and ostrich fat salami in turn had significantly higher TBA values than the sheeptail fat salami during storage. The keeping quality of the salamis were similar, a sensory evaluation panel preferred the pork backfat salami while the ostrich fat salami was the least preferred.

Afrikaans: Salami is 'n hoë vetinhoud (30-50 %) vleislekkerny wat deur verskillende sektore van die ekonomie, nl. huishoudings, tuisbedrywe, slaghuise en groot ondernemings, geproduseer word. Die samestelling van die produk varieer en salami hang gewoonlik in slaghuise of word in vertoonkabinette uitgestal. Met hoë temperatuur opberging kan salami, as gevolg van die hoë vetinhoud, bederf. Die gebrek aan eevormige bergingstoestande by Suid-Afrikaanse salami, het 'n studie genoodsaak, sodat die beste bergingstemperatuur vasgestel kon word. Dit berus op die waarneembare veranderinge in die lipiedfraksie van die produk. 'n Tipiese Suid-Afrikaanse salami is vervaardig, by drie temperature, nl. 4, 12 en 25 oe gestoor vir 15-30 dae. By 25 oe is betekenisvolle hoë lipiedhidrolise en oksidasie waargeneem, terwyl dit by 12 (JCgematigd en minimaal by 4 (JCwas. Met die veranderinge in die lipiedfraksie van die salami as uitgangspunt het dit geimpliseer dat 4 oe 'n uitstekende temperatuur, 12 oe 'n bevredigende en mees praktiese temperatuur en 25 oe 'n onaanvaarbare temperatuur vir opberging van Suid- Afrikaanse salami was. Die 12 (JCbergingstemperatuur is gebruik om die effek van hoë polionversadigde vetsuur (POVS) inhoud op die lipiedstabiliteit van die salami vas te stel. Hoër POVS vlakke het lipiedhidrolise en oksidasie benadeel, wat impliseer dat 'n tipiese Suid-Afrikaanse vark afrondingsrantsoen, wat aangeuul is met 3 % sonneblomolie (wat ooreenstem' met 57.88 ± 0.65 en 30.03 ± 4.53 POVS vlakke vir voer en rugvet onderskeidelik), die goedhouvermoë van salami kan benadeel. In 'n poging om salamiproduksie te diversifiseer is die lewensvatbaarheid van volstruis en skaap sterkvet as 'n plaasvervanger vir vark rugvet in salamivervaardiging gebruik. Volstruisvet is ryk in POVS, daarteenoor is skaap stertvet meer versadig, terwyl vark rugvet 'n intermediêre vetsuursamestelling het, soos gereflekteer in die salami vervaardig vanuit die onderskeie vetbronne. Lipiedhidrolise was betekenisvol hoër in skaap stetvet salami hoewel geen betekenisvolle verskille in die opbou van peroksiede waargeneem is nie. Die vark rugvetsalami en volstruisvet salami het weer betekenisvolle hoër TBA - waardes as die skaap stetvet salami tydens opberging getoon. Die goedhouvermoë van al drie salamis was dieselfde. 'n Sensoriese evaluering het getoon dat vark rugvet salami voorrang geniet, terwyl volstruisvet salami die minste verkies is.