The effect of conjugated linoleic acid supplementation on the quality of a cured, fermented pork sausage
The consumption of meat is increasingly linked to various diseases and this has already affected the growth of this sector of the food industry in some countries. Pork is seen as one of the major contributors to this problem. The meat industry reacted by using strategies such as dietary supplementation and direct addition of healthier lipids to manipulate the nutritional value of meat. The positive effects of CLA on human health are well documented and various strategies have been successfully employed in increasing the levels of CLA in different animal models such as pigs and eventually pork products. The effects CLA may have on a fermented meat product like salami has not been studied yet. No research have been reported where it was attempted to increase the nutritional value of salami, maintain acceptable product quality and include a therapeutically high level of CLA with the belief that it will benefit human health. In the first experiment of this study, 40 Duroc X Landrace gilts weighing on average 35 kg were randomly divided into two groups fed either a diet containing 0.5% sunflower oil (SFO) or a diet containing 0.5% conjugated linoleic acid (Luta-CLA® 60, BASF). These groups were further divided into two slaughter weight groups of ±70 kg and ±90 kg. After slaughter the lean meat and backfat from the loins of these animals were pooled by treatment group and utilized to manufacture salami. The aim was to determine if salami quality is influenced by slaughter weight and dietary supplementation of CLA. Both variables had major effects on the fatty acid composition and fatty acid ratios of the muscle and fat raw material as well as salami. The fatty acids and fatty acid ratios of technological importance were mostly positively influenced while the fatty acids and fatty acid ratios of nutritional and health concern were mostly negatively influenced by increased slaughter weight and dietary CLA supplementation. The microbial, physical, sensory and lipid stability parameters of salami were unaffected or inconsistently affected by both variables. Although dietary CLA was deposited successfully in muscle and fat, the deposition level was low. Consumption of a 28 g portion of salami manufactured from CLA enriched pork could only supply in 1% of the RDA for CLA. It could be concluded that although dietary supplementation of pork with CLA improved the technological properties of fat tissue it could not be considered a very successful approach to increase human consumption of CLA. In the second experiment of this study the aim was to increase the CLA content of salami to three different percentages (25%, 50% and 100%) of the RDA for CLA per 28 g portion of salami. This was accomplished through the direct addition of CLA (Tonalin® TG 80) in a pre-emulsified form with proportional decreases in the normally used pork BF content of the salamis. The salamis from these three treatment groups were then compared to a 100% pork BF control group for any possible effects on the microbial, physical and lipid stability parameters as well as fatty acid composition and fatty acid ratios. Microbial and sensory parameters were largely unaffected with varying effects on the physical and lipid stability parameters. Major effects on the fatty acid composition and fatty acid ratios of the salamis were observed. The partial replacement of pork BF and direct addition of CLA to salami proved to be an effective method of increasing CLA levels in salami in an attempt to improve the health aspects of salami to the point where it could be regarded as a functional food.