Remember Rosemary

From Shakespeare’s prose to herb-encrusted lamb chops, rosemary’s aromatic leaves are hard to forget. Tasting like camphoraceous pine with a hint of lemon, the narrow leaves of Rosmarinus officinalis, a small shrub related to mint, have flavored everything from potatoes to wine. Ancient Greeks and Romans used this Mediterranean native as a culinary and medicinal herb and, through the ages, rosemary developed a reputation for strengthening memory, turning it into a symbol for remembrance and fidelity.

A pinch of flavor

Rosemary’s assertive flavor works in sweet or savory applications. It complements many meats and poultry, as well as eggs and vegetables, including tomatoes, spinach, peas, mushrooms, squash and lentils. In Central Europe, cooks stuff a suckling pig with rosemary sprigs before spit-roasting it, and Italians often use it in a flatbread, schiaccia. It adds a unique accent to lemony beverages and desserts. Its flavor blends well with chives, thyme, chervil, parsley and bay leaf.

Rosemary leaves contain on average 1.0% to 2.5% essential oil, with flavor compounds such as cinoel, limonene, camphor, borneol, alpha-pinene and others contributing to the complex flavor.

Rosemary is available fresh, and in dried whole-leaf form or ground. “From a manufacturing standpoint,” says Peggy Iler, flavor applications manager, Kalsec, Kalamazoo, MI, “the use of fresh rosemary presents some problems in handling, availability and storage.” However, dried product has some flavor and shelf life issues. “An excellent alternative is the use of oleoresin rosemary,” she advises. “As with most herbs, when converting between fresh and dehydrated, a good rule of thumb is a replacement of 3 parts fresh to 1 part dehydrated.” The company’s oleoresin rosemary is approximately 25 times stronger than ground rosemary.

“Oleoresin rosemary can easily replace both the fresh and dehydrated herb in most food applications,” Iler says. “The extract provides all the flavor without the woody stem pieces associated with using either the fresh or dried herb. Unlike some herbs, the flavor of the extract from different growing regions tends to be fairly uniform, having only minor differences. However, the quality of the extract depends on the quality of the starting material. If old, dried product is used, the resulting extract will not have the lighter volatiles associated with higher-quality product.”

Antioxidant ability

Rosemary also contains many phenolic compounds with biological activities, including antioxidants carnosic acid, caffeic carnosol, rosmanol, isorosmanol and rosmari-diphenol. Other phenols that act as antioxidants include methylchavicol, carvacrol, eugenol and thymole, plus monoterpenoid ketone compounds, such as thujone, camphor, verbenone and carvone. Carnosic acid, the most-active antioxidant, has an antioxidant activity seven times higher than BHT and BHA (Journal of the American Oil Chemists Society, 1996; 73(4):507-514).

Rosemary extract can protect oils from oxidation, and low-flavor products impart little or no flavor to applications at effective levels. Rosemary extracts easily withstand typical food-processing temperatures.

“Proven effectiveness in meats is dependent upon the meat quality and the other ingredients used in the formulation and process,” says Jill McKeague, applications manager—antioxidants, Kalsec. “It’s best to add rosemary as early on in the process to maximize your oxidation-management potential; typical usage levels vary between 0.05% and 0.20%, depending on the product being used and the meat being stabilized. Water-miscible forms are available for brine solution in whole-muscle cuts, and oil-soluble forms are available for direct addition into ground meat to ensure uniform distribution. In oils, usage levels vary between 0.1% and 0.4%, depending on the product being used, the type of oil being stabilized and the application.”

A healthy herb

Rosemary’s antioxidant properties are also implicated in various health benefits. Not only does folklore ascribe improved cognitive effects, but it was also used for treating flu, viruses and colds, as well as helping lower blood sugar and raise blood pressure. Science backs up its reputation as a memory enhancer. One study found rosemary’s scent enhanced memory and increased alertness (International Journal of Neuroscience, 2003; 113(1):15-38).

Studies suggest rosemary’s carnosol and carnosic acid might have anti-inflammatory and anticarcinogenic activity. Several animal studies show positive effects against certain cancers, and some anti-HIV activity. They also might help protect the brain from free-radical damage, reducing risk of stroke, neurodegenerative conditions, and effects of aging.

Additionally, researchers at Kansas State University, Manhattan, found rosemary’s antioxidants prevent formation of carcinogenic compounds known as heterocyclic amines (HCAs) when meat is grilled. Surface application of rosemary extract can reduce HCAs by 30% to 100%.

Flavor, health and functionality: All in all, it’s hard to argue with the 17th-century herbalist John Gerard, who said rosemary “comforteth the cold, weak and feeble brain in a most wonderful manner.”