First evaluation of unfermented and fermented rooibos (Aspalathus linearis) in preventing lipid oxidation in meat products

- The antioxidant effect of green and fermented rooibos on meat products was tested.
- Different forms of green rooibos on ostrich meat patties were evaluated.
- Different fermented rooibos' concentrations on ostrich salami were tested.
- Shelf-life of ostrich meat patties was improved by green rooibos addition.
- Fermented rooibos retarded lipid oxidation of ostrich salami.

This study consisted of two trials aiming to evaluate, for the first time, the antioxidant potential of rooibos in meat products. With this purpose, the first trial evaluated three unfermented (green) rooibos forms (dried leaves, water extract, freeze-dried extract) added at 2% inclusion level to ostrich meat patties on an 8-day shelf-life trial. A Control group without green rooibos inclusion was also considered. The second trial evaluated the addition of different concentrations (0%, 0.25%, 0.5% and 1%) of a fermented rooibos extract to nitrite-free ostrich salami. The 2% green rooibos inclusion considerably lowered the TBARS content of ostrich patties, in this way extending their shelf-life. The fermented form (0.5% and 1%) was also effective in delaying lipid oxidation in ostrich salami until 15 days of ripening. The antioxidant potential of both green and fermented forms of rooibos in meat products was confirmed, even if its effect on lipid oxidation requires further study and long-term effects are not yet fully understood.