Rosemary extracts as natural food preservatives
What it found
Rosemary extracts and essential oils can slow down fat spoilage and fight food bacteria in lab tests and in some meat and oil products.
The authors say the effect depends on how the rosemary is prepared and how much is used.
What they found
Animal and lab studies
Antimicrobial effect
Rosemary essential oil and extracts inhibited the growth of bacteria such as E. coli, Bacillus cereus, Staphylococcus aureus and Salmonella in lab tests. In meat products, rosemary extracts reduced spoilage bacteria.
Animal feed studies
Feeding rosemary to broilers, ewes, cattle, lambs, pigs and turkeys improved the lipid stability of meat in many studies. However, some studies found no improvement in meat or eggs.
Other findings
Antioxidant compounds
The main antioxidant compounds in rosemary are carnosic acid and carnosol, which together are responsible for 90% of the antioxidant properties. These compounds scavenge free radicals and chelate metal ions.
Antioxidant effect in food
Adding rosemary extracts to beef, pork, oils and other foods reduced lipid oxidation and helped keep colour and sensory qualities. In some studies, rosemary extract was as effective as synthetic antioxidants.
Synergy with other antioxidants
Some studies found that rosemary extract can regenerate vitamin E and work together with it to slow oxidation. Other studies found no added benefit when combined with tocopherols.
Factors affecting activity
The antioxidant and antimicrobial strength of rosemary depends on the plant's fruiting stage, the extraction method, the presence of other compounds, and the concentration used.
What the authors conclude
“Because rosemary is a cheap, available, and a non-toxic herb, these considerations warrant the introduction of rosemary extracts or essential oils, with high phenolic compound contents, into the food industry.”
Also in their conclusions
- They conclude that rosemary extracts and essential oils can delay lipid oxidation in foods and biological systems.
- They advise that the antioxidant and antimicrobial activity depends on many factors, including the fruiting stage, extraction method, and concentration of active compounds.
- They say rosemary extracts could be used in functional foods, pharmaceutical products, and food preservation because rosemary is cheap, available, and non-toxic.
How it was done
Consumers want food without synthetic additives, so there is growing interest in natural preservatives. Rosemary is a cheap, available herb with antioxidant and antibacterial properties.
The authors reviewed published studies on how rosemary extracts and essential oils are made, what they contain, and how they work as antioxidants and antimicrobials in foods. They looked at lab tests, meat and oil products, and animal feed studies.
What it can’t tell you
- Most of the studies in this review were done in lab tests or in animals, not in people. They cannot show what effect rosemary has on human health.
- The review does not include human trials, so it cannot say whether eating rosemary or rosemary-preserved foods affects human disease risk.
- The studies used different rosemary preparations and doses, so it is hard to compare results directly.
Who paid
- Conflicts
- The authors declare no conflict of interest.
- Authors work at
- University of Murcia, Spain
The paper
- Title
- Antioxidant and Antimicrobial Properties of Rosemary ( Rosmarinus officinalis, L.): A Review
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Nieto G, Ros G, Castillo J (2018). Antioxidant and Antimicrobial Properties of Rosemary ( Rosmarinus officinalis, L.): A Review. Medicines (Basel, Switzerland). doi:10.3390/medicines5030098Free full textPubMed 30181448DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error